Fresh Brussels sprouts, whole and halved.

Brussels Sprouts

Q: What are Brussels sprouts good for?

They are a rich source of vitamin C and vitamin K and a source of fibre, folate and potassium. Health claims beyond that come from studies of cruciferous vegetables in general, which are mostly observational.

Q: Are Brussels sprouts safe with warfarin?

MedlinePlus lists Brussels sprouts as a vitamin K food and says to keep your intake the same day to day, because sudden changes can alter warfarin's effect. The NHS says you can still eat vitamin K foods but should ask your warfarin clinic. Do not change your medicine on your own.

Q: Do Brussels sprouts affect the thyroid?

A 2024 systematic review of 123 studies concluded that brassica vegetables eaten as part of the diet, particularly with adequate iodine, pose no adverse effects on thyroid function. If you have a thyroid condition, ask your clinician.

Q: Do Brussels sprouts cause gas?

Some people think so: in a UK survey of 516 adults, 23% said Brussels sprouts cause flatulence, though gas did not worry most respondents. This is perception, not a measured effect.

Q: Do Brussels sprouts prevent cancer?

Not shown. Observational studies link more cruciferous vegetables to lower colon cancer risk (odds ratio 0.80), but they cannot show cause, and the Linus Pauling Institute calls the evidence that isothiocyanates from these vegetables lower cancer risk insufficient.

Q: Are Brussels sprouts good for the heart?

Observational studies link more cruciferous vegetables, and fruit and vegetables generally, to less heart disease. One tiny trial of 18 people found a 2.5 mm Hg lower systolic pressure on a cruciferous diet. Neither is about Brussels sprouts alone.

Q: Do Brussels sprouts help blood sugar or diabetes?

Possibly a little, but evidence is weak. Four cohort studies link cruciferous vegetables to lower diabetes risk (RR 0.84), and one 18-person trial found slightly lower after-meal glucose. The authors say the clinical impact is uncertain.

Q: Does cooking change Brussels sprouts?

Cooking inactivates myrosinase, the enzyme that turns glucosinolates into sulforaphane-type compounds; light steaming for under 5 minutes keeps some (Linus Pauling Institute). A lab study found sous-vide cooking lost more glucosinolates than conventional cooking. No reliable figure for vitamin C loss in sprouts was found.

Q: Is it safe to eat Brussels sprouts raw?

The FDA says washing produce under running water reduces but does not eliminate bacteria, and that cooking thoroughly kills harmful bacteria. The FDA's special warning about raw sprouts is about seed sprouts such as alfalfa and mung bean; Brussels sprouts are cabbage-family buds, not seed sprouts (our reading).

Q: Are Brussels sprouts safe in pregnancy?

No special caution for the vegetable was found in the sources read. The FDA says pregnant women are especially vulnerable to foodborne illness, so wash produce under running water and cook it thoroughly. Ask your doctor.

Brassica oleracea (Gemmifera group) · also called Sprouts, coles de Bruselas (Spanish)

Brussels sprouts are the small leafy buds of a cabbage-family plant, usually eaten cooked. They are very rich in vitamin K and vitamin C. Eating more cruciferous vegetables is linked to better health in observational studies, but trials are few and small, and most are not about Brussels sprouts alone. The main caution is warfarin, because of the vitamin K.

General information, not medical advice. Last substantive update October 26, 2026 · Not medically reviewed. A named clinician has not signed off on this page. How this page is made

About Brussels Sprouts

Brussels sprouts are a nutritious cabbage-family vegetable, rich in vitamin K and vitamin C. They are a healthy food, not a proven remedy: most health claims come from studies of cruciferous vegetables in general, or from lab work on their plant compounds.

What it is

Brussels sprouts are the small buds of Brassica oleracea in the cabbage family (Brassicaceae). People eat them cooked, fresh or frozen. They are not the same as seed sprouts such as alfalfa.

USDA data for raw sprouts: 43 kcal per 100 g. One cup of raw sprouts (88 g) has about 38 kcal, 3.0 g protein, 3.3 g fibre, 156 micrograms vitamin K, 75 mg vitamin C, 54 micrograms folate (DFE), 342 mg potassium, 37 mg calcium and 1.2 mg iron. Cooked, frozen and canned values were not read.

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What the research shows

The firmest facts are about nutrients: vitamin K is needed for blood to clot and vitamin C helps make collagen, and Brussels sprouts are a rich source of both. These are not trials of sprouts.

Observational studies link more cruciferous vegetables to less heart disease, colon cancer and type 2 diabetes. They cannot show cause, and none was about Brussels sprouts alone.

The trials are few and small. Two feeding trials of 10 people each (1995 and 1997) looked at a urine marker of DNA damage with inconsistent results. A 1996 trial found no rise in HDL cholesterol. A 2024 trial of 18 older adults found a small blood pressure drop on a cruciferous diet.

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Cooking

Cooking inactivates myrosinase, the enzyme that makes sulforaphane-type compounds, though gut bacteria also convert glucosinolates; light steaming under 5 minutes keeps some enzyme (Linus Pauling Institute). A lab study found sous-vide cooking lost more glucosinolates than conventional cooking. No reliable figure for vitamin C loss in sprouts was found.

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Food versus concentrated compounds

Most work on glucosinolates and sulforaphane is lab or animal research or uses concentrated products. Results for those do not carry over to eating the vegetable, and the Linus Pauling Institute calls the evidence that isothiocyanates from cruciferous vegetables lower cancer risk insufficient.

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Amounts

This page gives no amounts to eat. Ask a doctor, pharmacist or dietitian what is right for you, especially if you take warfarin or have kidney problems.

At a glance

Traditional uses history, not proof

Eaten as a cooked vegetable, boiled, roasted or steamed
Long use as food is not proof that it treats any condition

Studied for research

Vitamin C source, high certainty for the nutrient, no sprout trial
Vitamin K for blood clotting, high certainty for the nutrient, no sprout trial
Heart disease and early death (cruciferous vegetables), low certainty, observational
Blood pressure, very low certainty (one 18-person trial)
Colon cancer and type 2 diabetes risk (cruciferous vegetables), low certainty, observational
Blood sugar, inflammation and DNA damage markers, very low or mixed certainty
HDL cholesterol, no effect found in one small trial

Main compounds

Vitamin K (phylloquinone)
Vitamin C
Folate
Glucosinolates (sinigrin, glucoraphanin)
Sulforaphane (formed from glucoraphanin)
Lutein and zeaxanthin
Beta-carotene
Potassium

Common forms

Fresh sprouts, usually cooked
Frozen sprouts
Canned or jarred sprouts (less common)
Sulforaphane and glucosinolate supplements are different products and are not covered by the studies on this page

Research links: MedlinePlus: Vitamin K · NHS: Warfarin · 2024 review: brassica vegetables and thyroid function · Research Library · Genes & Biomarkers Library

What it is and its history

Accepted scientific name: Brassica oleracea L. (Brussels sprouts are the gemmifera group)
Naming authority: L. (GBIF accepted species)
Synonyms: Brassica oleracea var. gemmifera DC. (GBIF lists this variety name as a synonym of Brassica oleracea)
Common names: Brussels sprouts (English); Sprouts (English); Coles de Bruselas (Spanish)
Family or group: Brassicaceae (the cabbage or mustard family), as given by GBIF and by the existing nutrient summary.
Classification: Plantae > Tracheophyta > Magnoliopsida > Brassicales > Brassicaceae > Brassica > Brassica oleracea
Native range: Not verified from a source read.
Habitat: Not verified from a source read.
What it looks like: Roots: Not verified.; Stems: Not verified.; Leaves: The edible part is the small, tightly layered bud. USDA gives household portions of one cup of raw sprouts as 88 g and one sprout as 19 g.; Flowers: Not verified.; Fruit: Not verified.
Cultivation: Not verified from a source read.
Harvest and processing: Sold fresh, frozen, and less often canned or jarred (existing nutrient summary). Usually cooked before eating. Cooking effects on glucosinolates are described in the compounds and mechanisms sections; no reliable figure for vitamin C loss in sprouts was found.
Look-alikes and adulterants: Name: Sprouts grown from seeds (alfalfa, mung bean, radish, clover, onion); Note: A different kind of food despite the similar name. Seed sprouts are grown in warm, humid conditions and the FDA gives special advice about eating them raw. Brussels sprouts are buds of a cabbage-family plant.; Name: Cabbage, broccoli, cauliflower, kale; Note: Other vegetables in the same species with their own pages. Cruciferous vegetable studies pool several of them.
Sustainability and conservation: Not assessed.

Photographs

Brussels sprouts close-up — Fresh Brussels sprouts.

What is inside, and how it may work

What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.

Main compounds

Compound	Family	Where it is concentrated	Activity studied	Level of evidence
Vitamin K (phylloquinone) PubChem 5284607	vitamin	Bud USDA: 177 micrograms per 100 g raw	Needed for blood-clotting proteins (MedlinePlus). Affects warfarin. ^{19 21 20}	Human data
Vitamin C (ascorbic acid) PubChem 54670067	vitamin	Bud USDA: 85 mg per 100 g raw	Needed to make collagen, repair tissue and absorb iron (MedlinePlus). ^{18 21}	Human data
Folate (vitamin B9) PubChem 135398658	vitamin	Bud USDA: 61 micrograms DFE per 100 g raw	B vitamin the body uses to make cells. No trial of Brussels sprouts and folate status was read. ²¹	Human data
Glucosinolates (including sinigrin and glucoraphanin)	sulfur-containing plant compounds	Bud Linus Pauling Institute table: about 104 mg total glucosinolates per half cup (44 g) raw Brussels sprouts, the highest of the vegetables in its table	Parent compounds of isothiocyanates. Sinigrin is the precursor of allyl isothiocyanate and glucoraphanin the precursor of sulforaphane (LPI). Human cancer-risk evidence is called insufficient by LPI. PubChem lookups: sinigrin CID 6911854, glucoraphanin CID 9548634. ¹⁶	Laboratory research
Sulforaphane (an isothiocyanate) PubChem 5350	isothiocyanate	Formed from glucoraphanin when sprouts are chopped or chewed Not given for Brussels sprouts in the sources read	Formed when the enzyme myrosinase meets glucoraphanin. Cooking inactivates myrosinase; light steaming under 5 minutes keeps some (LPI). Mostly studied in lab and animal work. ¹⁶	Laboratory research
Lutein (with zeaxanthin) PubChem 5281243	carotenoid	Bud USDA: 1,590 micrograms lutein plus zeaxanthin per 100 g raw	Carotenoid plant pigment. No Brussels-sprout trial for any outcome was read. ²¹	Human data
Beta-carotene PubChem 5280489	carotenoid	Bud USDA: 450 micrograms per 100 g raw	Orange-yellow pigment that the body can turn into vitamin A (general knowledge, not read in a source for this page). ²¹	Human data

Mechanisms, receptors and pathways

Target or pathway	Gene or receptor	What was found	Level
Vitamin K and blood clotting	Clotting factors II, VII, IX and X (named by MedlinePlus)	Vitamin K is used by the liver to make clotting proteins; warfarin works against this, so the vitamin K in food affects the medicine. ^{19 20}	Human data
Glucosinolates, myrosinase and isothiocyanates	Myrosinase (plant enzyme)	When raw cruciferous vegetables are chopped or chewed, myrosinase turns glucosinolates into reactive compounds such as isothiocyanates. Cooking inactivates myrosinase, though gut bacteria can also break glucosinolates down in the colon. Most effects of these compounds are known from lab and animal work. ¹⁶	Laboratory research
Warfarin clearance	Not specified in the abstract	A high daily intake of Brussels sprouts sped up warfarin clearance in 10 healthy volunteers who took one dose of warfarin; the mechanism was not stated in the abstract. ⁹	Human data

Absorption, metabolism and elimination

Absorption: Not established for most Brussels sprout nutrients in the sources read. LPI says a small fraction of intact glucosinolates may be absorbed in the small intestine and a large proportion reaches the colon.
Distribution: Not found.
Metabolism: Glucosinolates are broken down by myrosinase in raw sprouts or by gut bacteria in the colon (LPI). In a 1988 study, 400 g of sprouts a day for two weeks raised warfarin clearance in healthy volunteers.
Elimination: Not found.
Bioavailability: A lab study with simulated digestion found some glucosinolates fully degraded and others more resistant after cooking; this is not a study in people.

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Isolated compounds versus whole extracts

Most mechanism work is about glucosinolates and sulforaphane, tested in the lab or as concentrated products. The human trials read here fed whole vegetables. Results for a concentrated compound or extract do not carry over to eating the sprouts, and results for sprouts do not prove that an extract works. The Linus Pauling Institute says there is insufficient evidence that isothiocyanate exposure from cruciferous vegetables lowers cancer risk.

Nutritional composition

Nutrition from USDA FoodData Central (Brussels sprouts, raw, FDC 170383, SR Legacy, last updated 4/1/2019, read 2026-10-26). Per 100 g: 43 kcal, 3.38 g protein, 0.3 g fat, 8.95 g carbohydrate, 3.8 g fibre, 2.2 g total sugars, about 86 g water, 42 mg calcium, 1.4 mg iron, 23 mg magnesium, 389 mg potassium, 25 mg sodium, 0.337 mg manganese, 85 mg vitamin C, 61 micrograms folate (DFE), 38 micrograms vitamin A (RAE), 177 micrograms vitamin K, 0.219 mg vitamin B6, 450 micrograms beta-carotene and 1,590 micrograms lutein plus zeaxanthin. One cup of raw sprouts (88 g, about 4 to 5 sprouts at 19 g each): about 38 kcal, 3.0 g protein, 3.3 g fibre, 37 mg calcium, 1.2 mg iron, 342 mg potassium, 75 mg vitamin C, 54 micrograms folate, 156 micrograms vitamin K and about 1,400 micrograms lutein plus zeaxanthin. Figures vary with variety, ripeness and storage. Values for cooked, frozen or canned sprouts were not read.

10benefits and uses looked at

21studies and sources checked

High certaintybest evidence rating found

7lab markers tracked in trials

2 high certainty1 mixed findings3 low certainty3 very low certainty1 not enough evidence

What was looked at

The 10 benefits and uses checked for Brussels Sprouts, each with how strong the evidence is. Tap one to open it.

Vitamin C source (preventing scurvy)High certainty
Vitamin K for normal blood clottingHigh certainty
Heart disease and early death (cruciferous vegetables as a group)Low certainty
Blood pressure (cruciferous vegetables in a small trial)Very low certainty
Colon cancer risk (cruciferous vegetables as a group)Low certainty
Type 2 diabetes risk (cruciferous vegetables as a group)Low certainty
Blood sugar after meals (cruciferous vegetables in a small trial)Very low certainty
Inflammation markers (cruciferous vegetables, mixed results)Mixed findings
Oxidative DNA damage marker (Brussels sprouts feeding trials)Very low certainty
HDL (good) cholesterolNot enough evidence

Lab markers tracked in the studies

Heart disease, stroke and death24-hour systolic blood pressureBlood triglyceridesBlood glucose variability and after-meal glucoseInterleukin-6 (IL-6)Urinary 8-oxodG (oxidative DNA damage marker)HDL cholesterol and apolipoproteins A-I and A-II

What is Brussels Sprouts good for?

The main studied uses and how strong the human evidence is for each. Many results are for cruciferous vegetables as a group or for lab markers, not for eating Brussels sprouts.

Vitamin C sourceHigh certaintyBrussels sprouts are a rich vitamin C food: about 75 mg in one cup (88 g) of raw sprouts (USDA). Vitamin C is needed to make collagen and absorb iron (MedlinePlus). A nutrient fact, not a trial of sprouts. Normal blood clotting (vitamin K)High certaintyVitamin K is needed to make clotting proteins, and Brussels sprouts are a rich source: about 156 micrograms in one cup (88 g) of raw sprouts (USDA). A nutrient fact, not a trial of sprouts. Heart disease and early death (cruciferous vegetables)Low certaintyObservational studies link more cruciferous vegetables to less heart disease and fewer deaths. For fruit and vegetables combined, each 200 g a day went with 8% lower coronary heart disease risk (RR 0.92). This cannot show cause and is not about Brussels sprouts alone. Blood pressure (small trial)Very low certaintyOne crossover trial of 18 older adults found 300 g a day of cruciferous vegetables lowered 24-hour systolic pressure by 2.5 mm Hg versus root and squash vegetables. Tiny, two weeks, and Brussels sprouts were not named. Colon cancer risk (cruciferous vegetables)Low certaintyA 2025 meta-analysis found higher cruciferous vegetable intake linked to lower colon cancer (odds ratio 0.80). Mostly observational; the authors urge caution. The Linus Pauling Institute calls evidence for an isothiocyanate effect on cancer risk insufficient. Type 2 diabetes risk (cruciferous vegetables)Low certaintyFour cohort studies pooled showed 16% lower diabetes risk with the highest cruciferous vegetable intake (RR 0.84). Observational and not about Brussels sprouts alone. Blood sugar after meals (small trial)Very low certaintyIn the same 18-person trial, cruciferous vegetables gave slightly lower after-meal glucose (-0.14 mmol/L) than root and squash vegetables. The authors say the clinical impact is uncertain. Inflammation markersMixed findingsIn 63 healthy young adults a cruciferous diet lowered IL-6 by about 19%, but other markers did not change and one rose. The authors call the effects variable. DNA damage marker (lab)Very low certaintyTwo tiny feeding trials of 10 volunteers each gave 300 g of Brussels sprouts a day. A urine marker of DNA damage fell 28% in five men in the first trial, but results were inconsistent in the second and absent in women. HDL cholesterolNot enough evidenceA 3-week trial in healthy young men found Brussels sprouts did not raise HDL cholesterol.

Benefits, one by one

Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.

Vitamin C source (preventing scurvy)

High certainty

Brussels sprouts are a rich source of vitamin C. USDA lists about 75 mg in one cup (88 g) of raw sprouts. Vitamin C is needed to repair tissue and to absorb iron. This is a nutrient fact, not a trial of Brussels sprouts.

2 studiesRaw sprouts per USDA; usually eaten cooked.

Studies, doses and limits

What the trials found

MedlinePlus lists broccoli, Brussels sprouts and cauliflower among the vegetables with the highest sources of vitamin C and says that for most people vitamin C supplements or vitamin C-rich foods do not reduce the risk of getting the common cold. USDA lists 85 mg of vitamin C per 100 g of raw Brussels sprouts, about 75 mg in one cup (88 g).

Results

Brussels sprouts are a rich vitamin C food. No trial of Brussels sprouts for scurvy or any other vitamin C outcome was read.

Effect sizes as reported

USDA: 85 mg vitamin C per 100 g raw; about 75 mg per cup (88 g).

Why this rating

High for the nutrient role and for sprouts being a rich source (health-agency statement and USDA data). There is no Brussels-sprout-specific trial, and a varied diet normally supplies vitamin C. Cooking lowers vitamin C by amounts that depend on time and temperature; no reliable figure for sprouts was read.

Form and dose studied

Raw sprouts per USDA; usually eaten cooked.

Who was studied

Anyone eating a varied diet; scurvy is the disease of severe vitamin C shortage.

Limits

Nutrient fact, not a trial of Brussels sprouts. This page does not show that extra vitamin C from any source adds benefit in someone who already has enough. MedlinePlus says vitamin C does not reduce the risk of catching a cold for most people.

Why researchers looked

Brussels sprouts are named by MedlinePlus among the vegetables with the highest vitamin C, so people ask what that does for them.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Authoritative guidance

Vitamin C is needed to make collagen, to heal wounds, to repair cartilage, bones and teeth, and to help absorb iron (MedlinePlus). The body cannot make it and does not store it.

A proposed mechanism does not show that the effect happens in people.

None specific for the food.

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Vitamin K for normal blood clotting

High certainty

Vitamin K is needed for blood to clot. Brussels sprouts are a rich source: USDA lists 177 micrograms per 100 g, about 156 micrograms in one cup (88 g) of raw sprouts. This is a nutrient fact, not a trial of Brussels sprouts. If you take warfarin, the same vitamin K matters for a different reason: see the Safety tab.

2 studiesRaw sprouts per USDA; values vary with variety, ripeness and storage.

Studies, doses and limits

What the trials found

MedlinePlus says vitamin K is needed to make clotting factors in the liver and lists Brussels sprouts, broccoli, cauliflower and cabbage among the food sources. It says deficiency is very rare and can occur when the vitamin is not absorbed properly or after long-term antibiotic treatment. USDA lists 177 micrograms of vitamin K (phylloquinone) per 100 g of raw Brussels sprouts.

Results

The clotting role of vitamin K is well accepted and Brussels sprouts are a rich source. No trial of Brussels sprouts for clotting was read.

Effect sizes as reported

USDA: 177 micrograms vitamin K per 100 g raw; about 156 micrograms per cup (88 g).

Why this rating

High for the nutrient role and for sprouts being a rich source (health-agency statement and USDA data). There is no Brussels-sprout-specific trial, and a varied diet normally supplies vitamin K.

Form and dose studied

Raw sprouts per USDA; values vary with variety, ripeness and storage.

Who was studied

Anyone eating a varied diet.

Limits

Nutrient fact, not a trial of Brussels sprouts. This page does not show that extra vitamin K from any source adds benefit in someone who already has enough.

Why researchers looked

Brussels sprouts are named as a vitamin K food, so people ask what it does for the body.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Authoritative guidance

The liver uses vitamin K to make clotting proteins (clotting factors II, VII, IX and X). Without it, blood would not clot (MedlinePlus).

A proposed mechanism does not show that the effect happens in people.

People taking warfarin should keep vitamin K intake steady and ask their clinic; see the Safety tab.

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Heart disease and early death (cruciferous vegetables as a group)

Low certainty

People who eat more cruciferous vegetables (the cabbage family) have less heart disease and fewer early deaths in observational studies. This cannot prove the vegetables are the cause, and the studies were not about Brussels sprouts alone.

1 studiesWhole vegetables eaten as food.

Studies, doses and limits

What the trials found

A 2017 meta-analysis of 95 prospective studies found that fruit and vegetables combined were linked to lower risk of coronary heart disease (relative risk 0.92 per 200 g a day, 95% CI 0.90 to 0.94), stroke (0.84, 0.76 to 0.92) and death from any cause (0.90, 0.87 to 0.93). The abstract also says inverse associations were seen for cruciferous vegetables with cardiovascular disease and all-cause mortality, but gives no figure for cruciferous vegetables alone.

Results

Observational studies link more cruciferous vegetables to less cardiovascular disease and fewer deaths. The numbers above are for fruit and vegetables combined.

Effect sizes as reported

Fruit and vegetables combined per 200 g/day: coronary heart disease RR 0.92 (0.90-0.94); stroke RR 0.84 (0.76-0.92); all-cause mortality RR 0.90 (0.87-0.93).

Why this rating

Low, because the evidence is observational: people who eat more vegetables differ from others in many ways, and the studies are about cruciferous vegetables or fruit and vegetables as a group, not Brussels sprouts alone. The abstract gives no cruciferous-only number.

Form and dose studied

Whole vegetables eaten as food.

Who was studied

Adults in prospective cohort studies.

Limits

Cannot show cause. Brussels sprouts were not analysed on their own in the abstract read. Intake amounts and definitions of 'cruciferous' differ between studies.

Why researchers looked

Cruciferous vegetables are rich in vitamins, fibre and plant compounds, and population studies ask whether eating them goes with healthier hearts.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Unknown

Not established. Which nutrient or plant compound might matter, if any, is not shown by the studies read.

A proposed mechanism does not show that the effect happens in people.

None specific beyond the warfarin caution on the Safety tab.

Blood pressure (cruciferous vegetables in a small trial)

Very low certainty

In one small, short crossover trial of 18 older adults with mildly raised blood pressure, about 300 g a day of cruciferous vegetables lowered 24-hour systolic blood pressure by 2.5 mm Hg compared with root and squash vegetables. It is one tiny study and it did not name Brussels sprouts.

1 studiesCruciferous vegetables eaten as food in the trial's meals.

Studies, doses and limits

What the trials found

In the 2024 VESSEL randomised crossover trial, 18 adults (median age 68, 16 women, systolic pressure 120-160 mm Hg) ate about 300 g a day of cruciferous vegetables or of root and squash vegetables for two weeks each, with a two-week gap. Twenty-four-hour systolic pressure was 2.5 mm Hg lower after the cruciferous diet (95% CI -4.2 to -0.9; n=17), driven by daytime pressure (-3.6 mm Hg). Triglycerides were also lower (-0.2 mmol/L, 95% CI -0.4 to 0.0).

Results

A small effect on systolic pressure in one very small trial of a mix of cruciferous vegetables.

Effect sizes as reported

24-hour systolic BP -2.5 mm Hg (95% CI -4.2 to -0.9); daytime -3.6 mm Hg (-5.4 to -1.7); triglycerides -0.2 mmol/L (-0.4 to 0.0).

Why this rating

Very low: one trial of 18 people lasting two weeks, mostly older women, with a mix of cruciferous vegetables the abstract does not name. It has not been repeated in the abstracts read.

Form and dose studied

Cruciferous vegetables eaten as food in the trial's meals.

Who was studied

Older adults with mildly elevated blood pressure.

Limits

Tiny and short. Not Brussels sprouts alone. Whether the drop lasts or helps health outcomes was not tested.

Why researchers looked

Observational studies link cruciferous vegetables to less heart disease, so researchers tested whether eating them changes blood pressure.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Unknown

Not established in the abstract. The authors say the pathways are uncertain.

A proposed mechanism does not show that the effect happens in people.

None reported in the abstract.

Colon cancer risk (cruciferous vegetables as a group)

Low certainty

A 2025 meta-analysis found people who eat more cruciferous vegetables had about 20% lower odds of colon cancer. Most of the studies were observational, and the authors urge caution. The studies were not about Brussels sprouts alone.

3 studiesCruciferous vegetables as food.

Studies, doses and limits

What the trials found

A 2025 dose-response meta-analysis of 17 studies (7 cohort, 10 case-control; 97,595 people) found higher cruciferous vegetable intake linked to lower colon cancer (odds ratio 0.80, 95% CI 0.72 to 0.90), with a gradual drop in risk as intake rose. The 2017 fruit and vegetable meta-analysis also reported inverse associations of cruciferous vegetables with total cancer risk, without a figure in the abstract.

Results

Observational studies link more cruciferous vegetables to less colon cancer.

Effect sizes as reported

Colon cancer OR 0.80 (95% CI 0.72-0.90) for higher versus lower cruciferous vegetable intake.

Why this rating

Low: observational studies, many of them case-control (which depend on remembering past diet), with differing designs and residual confounding that the authors themselves point out. Cruciferous vegetables as a group, not Brussels sprouts alone.

Form and dose studied

Cruciferous vegetables as food.

Who was studied

Adults in cohort and case-control studies.

Limits

Cannot show cause. Not Brussels sprouts alone. Only colon cancer figures are quoted here; other cancers were not read.

Why researchers looked

Cruciferous vegetables contain glucosinolates, which lab studies link to cancer-related pathways, so researchers ask whether eating them goes with less cancer.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Laboratory research

Lab and animal work suggests breakdown products of glucosinolates (isothiocyanates) affect cancer-related pathways. The Linus Pauling Institute says there is insufficient evidence that isothiocyanate exposure from cruciferous vegetables lowers cancer risk in people.

A proposed mechanism does not show that the effect happens in people.

None specific.

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Type 2 diabetes risk (cruciferous vegetables as a group)

Low certainty

In a 2016 pooling of four cohort studies, people with the highest cruciferous vegetable intake had about 16% lower risk of developing type 2 diabetes. It is an observational link with only four studies and it is not about Brussels sprouts alone.

1 studiesCruciferous vegetables as food.

Studies, doses and limits

What the trials found

A meta-analysis of prospective cohort studies (306,723 people, 16,544 new type 2 diabetes cases; four studies for cruciferous vegetables) found highest versus lowest cruciferous vegetable intake linked to lower diabetes incidence (summary relative risk 0.84, 95% CI 0.73 to 0.96; I2 54.4%). Citrus fruit showed no link.

Results

Observational link to lower diabetes incidence.

Effect sizes as reported

RR 0.84 (95% CI 0.73-0.96), highest versus lowest intake.

Why this rating

Low: four observational cohort studies with moderate heterogeneity; cause not shown; not Brussels sprouts alone.

Form and dose studied

Cruciferous vegetables as food.

Who was studied

Adults in prospective cohorts.

Limits

Only four studies; older search (to 2014); cannot show cause.

Why researchers looked

Higher vegetable intake is linked to lower diabetes risk, so researchers asked about specific vegetable types.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Unknown

Not established in the abstract.

A proposed mechanism does not show that the effect happens in people.

None specific.

⁵

Blood sugar after meals (cruciferous vegetables in a small trial)

Very low certainty

In the same tiny 18-person crossover trial, cruciferous vegetables (about 300 g a day) gave steadier blood glucose and slightly lower after-meal glucose than root and squash vegetables. The authors say the clinical impact is uncertain. Brussels sprouts were not named.

1 studiesCruciferous vegetables as soup and meals.

Studies, doses and limits

What the trials found

In the VESSEL crossover trial (18 non-diabetic adults, median age 68), two weeks of 300 g/day cruciferous vegetables versus root and squash vegetables lowered glucose variability (-2.0%, 95% CI -2.8 to -1.1) and the 2-hour after-meal glucose response (-0.14 mmol/L, 95% CI -0.24 to -0.04), driven by the evening meal. Average glucose did not differ (p=0.411). Glycaemia was a pre-specified secondary outcome.

Results

Small improvements in after-meal glucose in a very small trial; average glucose unchanged.

Effect sizes as reported

Glucose variability -2.0% (-2.8 to -1.1); 2-hour response -0.14 mmol/L (-0.24 to -0.04); mean glucose p=0.411.

Why this rating

Very low: 18 people, two weeks, a secondary outcome, and the same participants as the blood pressure trial.

Form and dose studied

Cruciferous vegetables as soup and meals.

Who was studied

Non-diabetic older adults with raised blood pressure.

Limits

Tiny; not Brussels sprouts alone; people with diabetes were not studied.

Why researchers looked

Observational studies link cruciferous vegetables to less diabetes, so researchers tested glucose responses.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Unknown

Not established in the abstract.

A proposed mechanism does not show that the effect happens in people.

None reported in the abstract.

Inflammation markers (cruciferous vegetables, mixed results)

Mixed findings

In a trial of 63 healthy young adults, a cruciferous vegetable diet lowered one inflammation marker (IL-6) by about 19%, but other markers did not change and one rose. The authors call the effects variable. Brussels sprouts were not named.

1 studiesControlled diets of cruciferous vegetables.

Studies, doses and limits

What the trials found

In a 2014 randomised crossover trial, 63 healthy adults aged 20-40 ate four 14-day controlled diets: vegetable-free, single-dose cruciferous, double-dose cruciferous, and cruciferous plus carrot-family. IL-6 was lower on the double-dose cruciferous diet (-19%, 95% CI -30% to -0.1%) and the combined diet (-20%), IL-8 was higher after the combined diet (+16%), and CRP, TNF-alpha and soluble TNF receptors did not change. Results differed by GSTM1/GSTT1 gene type.

Results

Mixed: one marker lower, one higher, three unchanged.

Effect sizes as reported

IL-6 -19% (double-dose cruciferous); IL-8 +16% (combined diet); CRP, TNF-alpha no change.

Why this rating

Mixed: inconsistent biomarker results in healthy young adults, with subgroup findings that depend on gene type. Not Brussels sprouts alone.

Form and dose studied

Controlled diets of cruciferous vegetables.

Who was studied

Healthy adults aged 20-40.

Limits

Healthy people with no disease to improve; blood markers, not health outcomes.

Why researchers looked

Isothiocyanates from cruciferous vegetables affect inflammation pathways in lab work, so researchers measured blood markers.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Laboratory research

Isothiocyanates are thought to affect the NF-kappaB inflammation pathway (stated as background in the abstract); the trial did not confirm this.

A proposed mechanism does not show that the effect happens in people.

None reported in the abstract.

⁸

Oxidative DNA damage marker (Brussels sprouts feeding trials)

Very low certainty

Two small Dutch feeding trials gave 10 healthy volunteers 300 g of Brussels sprouts a day. In the first, a urine marker of DNA damage fell 28% in five men. In the second, it fell in four of five men but not in women. These are lab markers in tiny, old studies, not proof of lower cancer risk.

2 studiesCooked Brussels sprouts as food, 300 g a day in the trials (not advic…

Studies, doses and limits

What the trials found

In a 1995 randomised trial of 10 healthy non-smoking men, five ate 300 g of cooked Brussels sprouts daily for 3 weeks; their urinary 8-oxodG fell 28% (P=0.039) while controls did not change (P=0.72). A 1997 crossover trial of 10 non-smokers (5 men, 5 women), 1 week per diet, found a reduction in four of five men, one man with a large rise, and no effect in women.

Results

A lab marker fell in some men; no effect in women; results not consistent.

Effect sizes as reported

8-oxodG -28% in the 1995 sprouts group (P=0.039); no summary figure in the 1997 abstract.

Why this rating

Very low: two tiny trials (10 people each) from the 1990s, a lab marker rather than a health outcome, and inconsistent results between the two and between men and women.

Form and dose studied

Cooked Brussels sprouts as food, 300 g a day in the trials (not advice).

Who was studied

Healthy non-smoking adults.

Limits

Tiny and old. The authors' remarks about cancer risk are not shown by a urine marker.

Why researchers looked

Researchers wanted to see whether Brussels sprouts change markers linked to cancer-related damage.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Unknown

Not established. The authors suggest glucosinolate breakdown products may help the body's defences; the abstracts do not test this.

A proposed mechanism does not show that the effect happens in people.

None reported in the abstracts.

^{12 13}

HDL (good) cholesterol

Not enough evidence

A 3-week trial in healthy young men found that eating 300 g of Brussels sprouts a day did not raise HDL cholesterol. This is a no-effect result.

1 studiesCooked sprouts as food in the trial.

Studies, doses and limits

What the trials found

A controlled dietary trial in healthy non-smoking men aged 20-28 replaced 300 g of glucosinolate-free vegetables with 300 g of Brussels sprouts a day for 3 weeks and found no significant increase in apolipoprotein A-I, A-II, HDL cholesterol or HDL phospholipids.

Results

No significant change in HDL measures.

Effect sizes as reported

No significant change (figures not given in the abstract).

Why this rating

Insufficient: one small, short, old trial in young healthy men; the number of men in the sprouts trial is not stated in the abstract. It speaks only to HDL, not to overall cholesterol or heart health.

Form and dose studied

Cooked sprouts as food in the trial.

Who was studied

Healthy young men.

Limits

Old, small, short; LDL cholesterol results not stated in the abstract.

Why researchers looked

Researchers tested whether plant compounds that switch on liver enzymes might raise HDL cholesterol, as some drugs do.

Traditional use

Brussels sprouts are eaten as a cooked vegetable, usually boiled, roasted or steamed. Long use as food is not proof that it treats any condition.

Proposed mechanism Hypothesis

The hypothesis was that compounds inducing the cytochrome P-450 system might raise HDL. The result did not support it for Brussels sprouts.

A proposed mechanism does not show that the effect happens in people.

None reported.

⁷

Connections to the rest of health

How Brussels Sprouts connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.

Explore every connection: goals, body systems, organs, symptoms, genes

Kind of connection Connected to Search

A. Wellness goals

Connected to	Evidence status	Context	Studies
Blood Pressure Support	Very low certainty	Blood pressure (cruciferous vegetables in a small trial): In one small, short crossover trial of 18 older adults with mildly raised blood pressure, about 300 g a day of cruciferous vegetables lowered 24-hour systolic blood pressure by 2.5 mm Hg compared with root and squash vegetables. It is one tiny study and it did not name Brussels sprouts.	²
Blood Sugar Balance	Very low certainty	Blood sugar after meals (cruciferous vegetables in a small trial): In the same tiny 18-person crossover trial, cruciferous vegetables (about 300 g a day) gave steadier blood glucose and slightly lower after-meal glucose than root and squash vegetables. The authors say the clinical impact is uncertain. Brussels sprouts were not named.	³
Cholesterol Balance	Not enough evidence	HDL (good) cholesterol: A 3-week trial in healthy young men found that eating 300 g of Brussels sprouts a day did not raise HDL cholesterol. This is a no-effect result.	⁷

B. Body systems

Connected to	Kind of connection	Evidence status	Context	Studies
Immune System	Biological association	High certainty	Studied for: Vitamin C source (preventing scurvy) Studied for: Vitamin K for normal blood clotting	^{18 21 19 8 12 13}
Integumentary System	Biological association	High certainty	Studied for: Vitamin C source (preventing scurvy)	^{18 21}
Cardiovascular System	Biological association	High certainty	Studied for: Vitamin K for normal blood clotting Studied for: Heart disease and early death (cruciferous vegetables as a group)	^{19 21 1 2 7}
Digestive System	Biological association	Low certainty	Studied for: Colon cancer risk (cruciferous vegetables as a group)	^{6 1 16}
Endocrine System	Biological association	Low certainty	Studied for: Type 2 diabetes risk (cruciferous vegetables as a group) Studied for: Blood sugar after meals (cruciferous vegetables in a small trial)	^{5 3}

C. Body parts and organs

Connected to	Kind of connection	Evidence status	Context	Studies
Kidneys	Adverse effect or risk	Documented risk	Potassium-containing food; people with kidney disease may need to limit potassium-rich foods. Contains potassium; caution for kidney disease. Preparation or compound: Potassium in Brussels sprouts	^{17 21}

I. Biomarkers

Connected to	Kind of connection	Evidence status	Context	Studies
Heart disease, stroke and death	Biological association	Low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	¹
24-hour systolic blood pressure	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	²
Blood triglycerides	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	²
Blood glucose variability and after-meal glucose	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	³
Interleukin-6 (IL-6)	Biological association	Mixed findings	Measured in trials: lowered. A lab change is not the same as a health benefit.	⁸
Urinary 8-oxodG (oxidative DNA damage marker)	Biological association	Very low certainty	Measured in trials: lowered. A lab change is not the same as a health benefit.	^{12 13}
HDL cholesterol and apolipoproteins A-I and A-II	Biological association	Not enough evidence	Measured in trials: no-change. A lab change is not the same as a health benefit.	⁷

K. Biological pathways

Connected to	Kind of connection	Evidence status	Context	Studies
Vitamin K	Preliminary mechanism	Human	Brussels sprouts are a rich vitamin K food; vitamin K is needed for clotting and affects warfarin.	^{19 20}
Vitamin C	Preliminary mechanism	Human	Brussels sprouts are named by MedlinePlus among the vegetables with the highest vitamin C.	¹⁸
Potassium	Preliminary mechanism	Human	Brussels sprouts contain potassium; relevant for kidney disease and some blood pressure medicines.	^{17 21}

L. Active compounds

Connected to	Kind of connection	Evidence status	Context	Studies
Vitamin K (phylloquinone)	Biological association	Human	Needed for blood-clotting proteins (MedlinePlus). Affects warfarin. Preparation or compound: Bud	^{19 21 20}
Vitamin C (ascorbic acid)	Biological association	Human	Needed to make collagen, repair tissue and absorb iron (MedlinePlus). Preparation or compound: Bud	^{18 21}
Folate (vitamin B9)	Biological association	Human	B vitamin the body uses to make cells. No trial of Brussels sprouts and folate status was read. Preparation or compound: Bud	²¹
Glucosinolates (including sinigrin and glucoraphanin)	Biological association	In vitro	Parent compounds of isothiocyanates. Sinigrin is the precursor of allyl isothiocyanate and glucoraphanin the precursor of sulforaphane (LPI). Human cancer-risk evidence is called insufficient by LPI. PubChem lookups: sinigrin CID 6911854, glucoraphanin CID 9548634. Preparation or compound: Bud	¹⁶
Sulforaphane (an isothiocyanate)	Biological association	In vitro	Formed when the enzyme myrosinase meets glucoraphanin. Cooking inactivates myrosinase; light steaming under 5 minutes keeps some (LPI). Mostly studied in lab and animal work. Preparation or compound: Formed from glucoraphanin when sprouts are chopped or chewed	¹⁶
Lutein (with zeaxanthin)	Biological association	Human	Carotenoid plant pigment. No Brussels-sprout trial for any outcome was read. Preparation or compound: Bud	²¹
Beta-carotene	Biological association	Human	Orange-yellow pigment that the body can turn into vitamin A (general knowledge, not read in a source for this page). Preparation or compound: Bud	²¹

Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 26, 2026).

Evidence at a glance: what changed in 7 lab markers

Tap a number to show only those markers. Counts are markers, not people.

Metabolic11 Other5

The evidence

The research centre for Brussels Sprouts. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.

Evidence by outcome

Vitamin C source (preventing scurvy) 2 studies High certainty Vitamin K for normal blood clotting 2 studies High certainty Heart disease and early death (cruciferous vegetables as a group) 1 study Low certainty Blood pressure (cruciferous vegetables in a small trial) 1 study · 18 people in trials Very low certainty Colon cancer risk (cruciferous vegetables as a group) 3 studies Low certainty Type 2 diabetes risk (cruciferous vegetables as a group) 1 study Low certainty Blood sugar after meals (cruciferous vegetables in a small trial) 1 study · 18 people in trials Very low certainty Inflammation markers (cruciferous vegetables, mixed results) 1 study · 63 people in trials Mixed findings Oxidative DNA damage marker (Brussels sprouts feeding trials) 2 studies · 20 people in trials Very low certainty HDL (good) cholesterol 1 study Not enough evidence

Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).

How we rate evidence

High certainty

Several well-run trials or reviews agree; further research is unlikely to change the picture much.

Moderate certainty

Good trials point the same way, but some doubt remains.

Low certainty

Small, short or inconsistent trials. The finding could change with better research.

Very low certainty

Very little or very weak human data. Treat as a possibility only.

Mixed findings

Trials or reviews disagree with each other.

Not enough evidence

Not enough human research to say either way.

Evidence against

Good research found no benefit, or found harm.

We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We started from our existing Brussels sprouts summary, re-checked nutrition at USDA FoodData Central, read the health agency pages (NHS, MedlinePlus, FDA) and the Linus Pauling Institute, and searched PubMed for reviews, trials and surveys. Only abstracts were read for studies. Items we could not verify are flagged in the research gaps.

Study library: every study we checked 21

Design Research type Year from Search

Study	Design	People	Product, dose, length	Result
Aune 2017 Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality-a systematic review and dose-response meta-analysis of prospective studies. Int J Epidemiol · PMID 28338764 · DOI	Systematic review meta analysis	Adults in 95 prospective studies (142 publications)	Fruit and vegetable intake as food Fruit and vegetables Per 200 g/day (analysis unit, not advice) Prospective follow-up · vs Lower intake	For fruit and vegetables combined, each 200 g/day was linked to lower risk of coronary heart disease, stroke, total cancer and death from any cause. The abstract says inverse associations were seen for cruciferous vegetables with cardiovascular disease and all-cause mortality, and for cruciferous and green-yellow vegetables with total cancer risk. A summary figure for cruciferous vegetables alone is not given in the abstract. Combined fruit and vegetables per 200 g/day: coronary heart disease RR 0.92; stroke RR 0.84; all-cause mortality RR 0.90 (CHD 0.92 (95% CI 0.90-0.94); stroke 0.84 (0.76-0.92); all-cause mortality 0.90 (0.87-0.93)) Methods, limits and funding Outcomes: Coronary heart disease, stroke, cardiovascular disease, total cancer, all-cause mortality Limitations: Prospective observational studies cannot show cause; people who eat more vegetables differ in other ways. The combined figures are not for Brussels sprouts. No cruciferous-only figure in the abstract. Funding and conflicts: Not stated in the abstract. Read: abstract
Connolly 2024 Cruciferous vegetables lower blood pressure in adults with mildly elevated blood pressure in a randomized, controlled, crossover trial: the VEgetableS for vaScular hEaLth (VESSEL) study. BMC Med · PMID 39218859 · DOI	Controlled trial	18 18 adults, median age 68, 16 of them women, with mildly elevated blood pressure (systolic 120-160 mm Hg)	Cruciferous vegetables as food, compared with root and squash vegetables (the abstract does not list which cruciferous vegetables) Vegetables About 300 g/day with lunch and dinner (study design, not advice) Two 2-week diets with a 2-week washout, crossover · vs Root and squash vegetables	Twenty-four-hour systolic blood pressure fell more after the cruciferous diet than after the root and squash diet, mainly in the daytime. Serum triglycerides were also lower. Adherence was high and confirmed by biomarkers. 24-hour systolic BP difference -2.5 mm Hg; daytime -3.6 mm Hg; triglycerides -0.2 mmol/L (24-hour SBP -4.2 to -0.9 (P=0.002, n=17); daytime -5.4 to -1.7; triglycerides -0.4 to 0.0 (P=0.047)) Methods, limits and funding Outcomes: 24-hour systolic blood pressure (main outcome), triglycerides Limitations: Very small (18 people), short (2 weeks), mostly older women, a mix of cruciferous vegetables not named in the abstract, not Brussels sprouts alone. Funding and conflicts: The authors declare no competing interests. Registered: ACTRN12619001294145. Registration: ACTRN12619001294145 Read: abstract
Connolly 2025 Cruciferous vegetables improve glycaemic control compared to root/squash vegetables in a randomized, controlled, crossover trial: The VEgetableS for vaScular hEaLth (VESSEL) study. Diabetes Obes Metab · PMID 40375391 · DOI	Controlled trial	18 18 non-diabetic adults with elevated blood pressure, median age 68, 89% women	Cruciferous vegetables as soup and meals, compared with root and squash vegetables (the abstract does not list which cruciferous vegetables) Vegetables 300 g/day (study design, not advice) Two 2-week diets with a 2-week washout, crossover · vs Root and squash vegetables	Glucose variability and the 2-hour after-meal glucose response were lower on the cruciferous diet, driven by the evening meal. Average glucose did not differ. Glucose variability -2.0%; 2-hour after-meal glucose -0.14 mmol/L (Variability -2.8 to -1.1 (p<0.001); 2-hour response -0.24 to -0.04 (p=0.005); mean glucose p=0.411) Methods, limits and funding Outcomes: Blood sugar variability and after-meal glucose (a pre-specified secondary outcome, flash glucose monitor) Limitations: Same 18 people as the blood pressure trial; very small; a secondary outcome; the authors say the clinical impact is uncertain. Funding and conflicts: The authors declare no competing interests. Registered: ACTRN12619001294145. Registration: ACTRN12619001294145 Read: abstract
Galanty 2024 Do Brassica Vegetables Affect Thyroid Function?-A Comprehensive Systematic Review. Int J Mol Sci · PMID 38612798 · DOI	Systematic review human, animal and lab	123 articles of in vitro, animal and human studies of brassica plants and extracts and thyroid function	Brassica vegetables and extracts (not Brussels sprouts alone) Vegetables and extracts Varied Varied · vs Varied	The vast majority of results cast doubt on earlier assumptions that brassica plants have antithyroid effects in humans. The authors say that including brassica vegetables in the daily diet, particularly with adequate iodine intake, poses no adverse effects on thyroid function. Not given in the abstract (Not given in the abstract) Methods, limits and funding Outcomes: Thyroid mass and histology, TSH, T3, T4, iodine uptake, thyroid cancer cells Limitations: Mixes in vitro, animal and human studies and also extracts; the abstract gives no separate figure for people with thyroid disease or low iodine. Funding and conflicts: The authors declare no conflicts of interest. Read: abstract
Jia 2016 Consumption of citrus and cruciferous vegetables with incident type 2 diabetes mellitus based on a meta-analysis of prospective study. Prim Care Diabetes · PMID 26778708 · DOI	Systematic review meta analysis	306723 306,723 adults in 7 prospective cohort studies (16,544 type 2 diabetes cases); 4 studies for cruciferous vegetables	Cruciferous vegetables as food (not Brussels sprouts alone) Vegetables Highest versus lowest intake 4.6 to 24 years of follow-up · vs Lowest intake	Highest cruciferous vegetable intake was linked to a lower rate of new type 2 diabetes. Citrus fruit showed no link. Heterogeneity was moderate. Summary relative risk 0.84 (95% CI 0.73-0.96; I2 54.4%) Methods, limits and funding Outcomes: Incident type 2 diabetes Limitations: Only four cohort studies for cruciferous vegetables; observational so cannot show cause; not Brussels sprouts alone. Funding and conflicts: Not stated in the abstract. Read: abstract
Lai 2025 Cruciferous vegetables intake and risk of colon cancer: a dose-response meta-analysis. BMC Gastroenterol · PMID 40790161 · DOI	Systematic review meta analysis	97595 97,595 people in 17 studies (7 cohort, 10 case-control)	Cruciferous vegetables as food (not Brussels sprouts alone) Vegetables Not given in the abstract Varied · vs Lower intake	Higher cruciferous vegetable intake was linked to lower colon cancer risk, with a non-linear dose-response. The authors say the findings should be read cautiously because study designs, diet questionnaires and residual confounding differ. Odds ratio 0.80 (95% CI 0.72-0.90) Methods, limits and funding Outcomes: Colon cancer Limitations: Observational (mostly case-control plus cohort) so cannot show cause; case-control studies rely on memory of past diet; cruciferous vegetables as a group, not Brussels sprouts alone. Funding and conflicts: The authors declare no competing interests. Read: abstract
Nanjee 1996 Do dietary phytochemicals with cytochrome P-450 enzyme-inducing activity increase high-density-lipoprotein concentrations in humans? Am J Clin Nutr · PMID 8901789 · DOI	Controlled trial	Healthy non-smoking men aged 20-28	Brussels sprouts as food (one of two trials; the other used eugenol capsules) Buds 300 g a day in place of 300 g glucosinolate-free vegetables (study design, not advice) 3 weeks · vs Glucosinolate-free vegetables	No significant increase in any of the HDL measures after three weeks of Brussels sprouts. No significant change (Not given in the abstract) Methods, limits and funding Outcomes: Plasma apolipoprotein A-I and A-II, HDL cholesterol, HDL phospholipids Limitations: Small, short, young healthy men; number of men in the sprouts trial is not given in the abstract. Funding and conflicts: Not stated in the abstract. Read: abstract
Navarro 2014 Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults. J Nutr · PMID 25165394 · DOI	Controlled trial	63 63 healthy adults aged 20-40 (32 men, 31 women)	Controlled diets with cruciferous vegetables (single and double amount) and cruciferous plus carrot-family vegetables (the abstract does not name the vegetables) Vegetables 7 or 14 g of vegetables per kg body weight per day (study design, not advice) Four 14-day diets with 21-day washouts, crossover · vs Vegetable-free basal diet	IL-6 was lower on the double-dose cruciferous diet and on the cruciferous plus carrot-family diet. IL-8 was higher after the combined diet. CRP, TNF-alpha and the soluble receptors did not change. Results differed by gene type (GSTM1/GSTT1) and the authors call them inconsistent. IL-6 -19% (double-dose cruciferous) and -20% (cruciferous plus carrot family); IL-8 +16% (combined) (IL-6 95% CI -30% to -0.1% and -31% to -0.7%; IL-8 +4.2% to +35.2%) Methods, limits and funding Outcomes: Blood levels of IL-6, IL-8, CRP, TNF-alpha and soluble TNF receptors Limitations: Young healthy adults; mixed biomarker results; subgroup findings by gene type; not Brussels sprouts alone. Funding and conflicts: Authors report no conflicts of interest. Read: abstract
Ovesen 1988 The effect of a diet rich in brussels sprouts on warfarin pharmacokinetics. Eur J Clin Pharmacol · PMID 3203715 · DOI	Clinical trial	10 10 healthy subjects	Brussels sprouts as food, with a single oral dose of warfarin before and after the diet Buds 400 g a day for 2 weeks (study design, not advice) 2 weeks · vs Same people before the diet	After two weeks of 400 g of Brussels sprouts a day, warfarin disposal was faster: the elimination rate constant rose 29%, metabolic clearance rose 27% and plasma AUC fell 16%. The authors conclude a high intake might contribute to less anticoagulation. Elimination rate +29%; metabolic clearance +27%; AUC -16% (Not given in the abstract) Methods, limits and funding Outcomes: Warfarin elimination rate, clearance and blood levels (AUC) Limitations: Ten healthy people, a single 20 mg warfarin dose given before and after the diet, and no blood-clotting test (such as INR) reported in the abstract. It was not done in people who take warfarin long term. Its direction is the opposite of what vitamin K alone would suggest, so it does not replace the advice to keep intake steady. Funding and conflicts: Not stated in the abstract. Read: abstract
Sadowska-Rociek 2024 The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans. Foods · PMID 39335916 · DOI	Laboratory study none (food lab study)	Brussels sprout samples, cooked and then put through a simulated digestion in the lab	Brussels sprouts cooked by several methods Buds · vs Conventional cooking	Sous-vide cooking led to significantly higher losses of glucosinolates than conventional cooking. No significant differences were seen in isothiocyanates and indoles. Some individual glucosinolates were completely degraded after digestion, while others were more resistant. Not given in the abstract (Not given in the abstract) Methods, limits and funding Outcomes: Glucosinolates, isothiocyanates and indoles before and after simulated digestion Limitations: Lab analysis and simulated digestion, not people; it does not show any health effect. Funding and conflicts: The authors declare no conflicts of interest. Read: abstract
Thomson 2025 Prevalence of gastrointestinal symptoms in the UK adult population and perceived effects of foods. Eur J Nutr · PMID 40848137 · DOI	Survey	516 516 UK adults who answered an online questionnaire (85% women, median age 38)	Perceptions of foods, including Brussels sprouts Vegetables	The most common perceptions were that beans (34%) and Brussels sprouts (23%) cause flatulence. Although flatulence was attributed to some fermentable fibre-rich foods, the symptom did not worry most respondents. 23% of respondents perceived Brussels sprouts as causing flatulence (Not applicable) Methods, limits and funding Outcomes: Gastrointestinal symptoms and which foods people think cause them Limitations: Self-reported perception in an online survey, mostly women; it does not measure actual gas production or show cause. Funding and conflicts: Not stated in the abstract. Read: abstract
Verhagen 1995 Reduction of oxidative DNA-damage in humans by brussels sprouts. Carcinogenesis · PMID 7728983 · DOI	Controlled trial	10 10 healthy non-smoking men	Brussels sprouts (cooked) in place of a glucosinolate-free vegetable Buds 300 g of cooked Brussels sprouts a day (study design, not advice) 3 weeks after a 3-week run-in · vs 5 men on a diet free of cruciferous vegetables	In the five men eating Brussels sprouts, urinary 8-oxodG fell by 28%. The five controls showed no change. 8-oxodG -28% in the sprouts group (P=0.039); controls no change (P=0.72) (Not given in the abstract) Methods, limits and funding Outcomes: Urinary 8-oxodG (a marker of oxidative DNA damage) Limitations: Only 10 men; a lab marker, not a disease outcome; 30-year-old study; conclusion language about cancer risk is the authors' and is not shown by this marker. Funding and conflicts: Not stated in the abstract. Read: abstract
Verhagen 1997 Effect of Brussels sprouts on oxidative DNA-damage in man. Cancer Lett · PMID 9103270 · DOI	Controlled trial	10 10 non-smoking volunteers (5 men, 5 women)	Brussels sprouts as food, crossover with a glucosinolate-free vegetable diet Buds 300 g a day (study design, not advice) 1 week per diet, crossover · vs 300 g glucosinolate-free vegetables	In four of five men 8-oxodG fell, but one man had very high excretion that rose further on sprouts. In women there was no effect. Not given as a summary figure (Not given in the abstract) Methods, limits and funding Outcomes: Urinary 8-oxodG Limitations: Only 10 people and 1 week per diet; results differed between men and women; a lab marker. This is the follow-up to the 1995 study and does not repeat its finding in women. Funding and conflicts: Not stated in the abstract. Read: abstract
s-fda-produce FDA: Selecting and Serving Produce Safely · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-gbif-brassica-oleracea GBIF Backbone: Brassica oleracea L. (usageKey 3042845) · Source	Reference database n/a			Methods, limits and funding Read: full-text
s-lpi-isothiocyanates Linus Pauling Institute: Isothiocyanates · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-medlineplus-potassium MedlinePlus: Potassium in diet · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-medlineplus-vitc MedlinePlus: Vitamin C · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-medlineplus-vitk MedlinePlus: Vitamin K · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-nhs-warfarin NHS: Warfarin · Source	Health agency n/a			Methods, limits and funding Read: full-text
s-usda-fdc-170383 USDA FoodData Central: Brussels sprouts, raw (FDC 170383) · Source	Reference database n/a			Methods, limits and funding Read: full-text

What we do not know yet

No trial of eating Brussels sprouts was found for heart disease, blood pressure, cancer, diabetes or inflammation; most evidence is for cruciferous vegetables in general.
The two feeding trials that did use Brussels sprouts were tiny, from the 1990s, and measured a lab marker.
No source read describes Brussels sprout allergy; no relevant case report was found.
The 1988 warfarin study reported no clotting test, and no study of long-term warfarin users was found.
Oxalate, FODMAP, histamine, pesticide residues, heavy metals, nitrate, pregnancy and breastfeeding specifics were not researched.

How new research is added

New studies are found by a saved PubMed search and placed in a review queue before the page changes.

Lab markers

What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".

Metabolic 2

▼

Blood triglycerides

Lowered in trials

A type of fat in the blood, measured from a blood sample.

Very low certainty

Results and what it means

Why it was measured

High triglycerides are a heart-disease risk marker.

Statistical vs. clinical meaning

Borderline result in a very small trial.

Safety implication

None specific.

Study	Result	People	Product
²	-0.2 mmol/L versus root and squash vegetables (95% CI -0.4 to 0.0, P=0.047)	18 older adults with mildly elevated blood pressure	About 300 g/day cruciferous vegetables for 2 weeks (mix not named)

●

HDL cholesterol and apolipoproteins A-I and A-II

No clear change in trials

HDL is often called good cholesterol; apolipoproteins A-I and A-II are its main proteins.

Not enough evidence

Results and what it means

Why it was measured

Low HDL is linked to higher heart-disease risk.

Statistical vs. clinical meaning

One small old trial; no effect seen.

Safety implication

None specific.

Study	Result	People	Product
⁷	No significant increase in apo A-I, apo A-II, HDL cholesterol or HDL phospholipids	Healthy non-smoking men aged 20-28	300 g Brussels sprouts a day for 3 weeks

⁷

Other 5

▼

Heart disease, stroke and death

Lowered in trials

How many people in a study develop heart disease or stroke, or die.

Low certainty

Results and what it means

Why it was measured

These are the outcomes that matter most to health, so population studies count them.

Statistical vs. clinical meaning

An association in observational studies, not proof that vegetables prevent disease.

Safety implication

None specific.

Study	Result	People	Product
¹	Fruit and vegetables combined per 200 g/day: coronary heart disease RR 0.92 (95% CI 0.90-0.94), stroke RR 0.84 (0.76-0.92), all-cause mortality RR 0.90 (0.87-0.93). Inverse associations also seen for cruciferous vegetables (no figure in the abstract)	Adults in 95 prospective studies	Fruit and vegetables as food (not Brussels sprouts alone)

▼

24-hour systolic blood pressure

Lowered in trials

The top blood pressure number, averaged over 24 hours with a wearable monitor.

Very low certainty

Results and what it means

Why it was measured

Raised blood pressure is a major risk for heart disease and stroke.

Statistical vs. clinical meaning

A small change in one tiny trial; long-term benefit not tested.

Safety implication

None specific.

Study	Result	People	Product
²	-2.5 mm Hg versus root and squash vegetables (95% CI -4.2 to -0.9), daytime -3.6 mm Hg	18 older adults with mildly elevated blood pressure	About 300 g/day cruciferous vegetables for 2 weeks (mix not named; not Brussels sprouts alone)

▼

Blood glucose variability and after-meal glucose

Lowered in trials

How much blood sugar swings through the day, and how high it rises in the two hours after a meal, measured with a skin-worn glucose sensor.

Very low certainty

Results and what it means

Why it was measured

Smaller swings and lower after-meal peaks are considered favourable for metabolic health.

Statistical vs. clinical meaning

The authors say the clinical impact is uncertain.

Safety implication

None specific.

Study	Result	People	Product
³	Variability -2.0% (95% CI -2.8 to -1.1); 2-hour after-meal glucose -0.14 mmol/L (-0.24 to -0.04); mean glucose no difference (p=0.411)	18 non-diabetic older adults	300 g/day cruciferous vegetables for 2 weeks versus root and squash vegetables (mix not named)

▼

Interleukin-6 (IL-6)

Lowered in trials

A blood protein that rises with inflammation.

Mixed findings

Results and what it means

Why it was measured

A common marker of whole-body inflammation.

Statistical vs. clinical meaning

Inconsistent across markers; the authors call the effects variable.

Safety implication

None specific.

Study	Result	People	Product
⁸	IL-6 -19% (95% CI -30% to -0.1%) on double-dose cruciferous diet; -20% on cruciferous plus carrot-family diet; CRP, TNF-alpha no change; IL-8 +16% on the combined diet	63 healthy adults aged 20-40	14-day controlled cruciferous diets (vegetables not named)

⁸

▼

Urinary 8-oxodG (oxidative DNA damage marker)

Lowered in trials

A compound passed in urine when DNA has been damaged by oxidation.

Very low certainty

Results and what it means

Why it was measured

Used as a lab marker of oxidative stress; it is not a disease outcome.

Statistical vs. clinical meaning

A lab marker in tiny trials with inconsistent results.

Safety implication

None specific.

Study	Result	People	Product
¹²	-28% in five men eating 300 g cooked Brussels sprouts a day for 3 weeks (P=0.039); no change in five controls	10 healthy non-smoking men	Cooked Brussels sprouts
¹³	Reduced in four of five men; one man much higher; no effect in women	10 non-smokers (5 men, 5 women)	300 g Brussels sprouts a day for 1 week

^{12 13}

Safety

What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.

Main points to know 5

Warfarin: Brussels sprouts are rich in vitamin K, so keep your intake steady and ask your clinic. MedlinePlus lists Brussels sprouts among the vitamin K foods and says that if you take warfarin you may need to eat the same amount of vitamin K foods every day, because sudden changes can change how the medicine works. The NHS says foods high in vitamin K, such as broccoli, spinach and other green leafy vegetables, can affect warfarin: you can still eat them, but talk to your warfarin clinic. USDA lists 177 micrograms per 100 g raw. Do not change a prescribed medicine on your own. Authoritative guidance ^{19 20 21}
A 1988 study found very large amounts sped up warfarin clearance in 10 healthy people. Ten healthy people took a single dose of warfarin before and after two weeks of 400 g of Brussels sprouts a day. The sprouts diet raised warfarin clearance by 27%, and the authors said this might contribute to less anticoagulation. This old small study did not report a clotting test and does not replace the advice above: keep your intake steady and tell your warfarin clinic about big diet changes. Clinical trial ⁹
Gas and bloating: some people notice it, but it is a perception. In a 2025 UK survey of 516 adults, 23% said they think Brussels sprouts cause flatulence. The authors note that this symptom did not worry most respondents. This is self-reported perception, not a measured effect. Survey ¹¹
Thyroid: a 2024 review found no harm from eating brassica vegetables, especially with enough iodine. Cabbage-family vegetables have long been called goitrogenic (thyroid-suppressing). A 2024 systematic review of 123 studies concluded that the vast majority of results cast doubt on antithyroid effects in humans and that including brassica vegetables in the diet, particularly with adequate iodine intake, poses no adverse effects on thyroid function. If you have a thyroid condition, ask your clinician about your own diet. Systematic review ⁴
Kidney disease and some blood pressure medicines: Brussels sprouts contain potassium. USDA lists 389 mg of potassium per 100 g of raw Brussels sprouts. MedlinePlus says people with kidney problems, particularly those on dialysis, should not eat too many potassium-rich foods, and names ACE inhibitors, ARBs and potassium-sparing diuretics (spironolactone, triamterene, amiloride) among causes of high blood potassium. MedlinePlus does not name Brussels sprouts on that page. Ask a clinician about potassium-rich foods. Authoritative guidance ^{17 21}

Side effects 2

Effect	How often	Severity and recovery	Evidence
Gas (flatulence), as perceived by survey respondents Self-reported perception in an online survey, mostly women. No measured gas production and no source for a remedy was read.	23% of 516 UK adults said they think Brussels sprouts cause flatulence	not stated (the symptom did not worry most respondents) Not stated	Survey ¹¹
Faster warfarin clearance after a high daily intake A 1988 single-dose study with 400 g of Brussels sprouts a day for two weeks. No clotting test was reported in the abstract.	Seen as group averages in 10 healthy people (clearance +27%, elimination rate +29%)	not stated Not stated	Clinical trial ⁹

Liver

No liver injury from eating Brussels sprouts was found. A liver-safety source (such as LiverTox) was not searched for this food page.

How often. No frequency was found.

Monitoring. No agency monitoring advice was found.

This is a safety connection. It is not evidence that Brussels Sprouts supports liver health.

Medicines and supplements 4

With	Why it matters	Importance	Evidence	What to do
Warfarin (blood thinner) prescription	Vitamin K helps blood clot, and warfarin works by lowering vitamin K activity. Brussels sprouts are a rich vitamin K food (USDA: 177 micrograms per 100 g raw).	MedlinePlus lists Brussels sprouts as a vitamin K food and says sudden changes in vitamin K intake can change the effect. The NHS says you can still eat foods high in vitamin K but should ask your warfarin clinic.	Authoritative guidance High certainty ^{19 20 21}	Keep your intake steady from day to day and tell your warfarin clinic before big diet changes. Do not change your medicine on your own. The NHS says do not take vitamin K supplements while taking warfarin.
Warfarin (clearance in healthy volunteers) prescription	After two weeks of 400 g Brussels sprouts a day, warfarin clearance rose in 10 healthy volunteers who took a single dose. How this happens was not stated in the abstract.	The authors say a high intake might contribute to less anticoagulation. No clotting test was reported, and the people did not take warfarin long term.	Clinical trial Very low certainty ⁹	Tell your warfarin clinic if your intake of Brussels sprouts or other cabbage-family vegetables changes a lot.
Medicines that raise blood potassium (ACE inhibitors, ARBs, potassium-sparing diuretics) prescription	These medicines can raise potassium in the blood (MedlinePlus). Brussels sprouts contain potassium (USDA: 389 mg per 100 g raw).	MedlinePlus does not name Brussels sprouts; the link is our reading of two separate facts. Normal food amounts have not been tested in a trial.	Authoritative guidance Low certainty ^{17 21}	If you take one of these medicines or have kidney disease, ask a clinician or pharmacist about potassium-rich foods.
Vitamin K supplements supplement	Same vitamin as in Brussels sprouts, in concentrated form.	The NHS says not to take vitamin K supplements while on warfarin.	Authoritative guidance High certainty ²⁰	Ask a clinician or pharmacist first.

Who should check first 5

Situation	Advice	Evidence
Taking warfarin	Keep vitamin K intake steady and follow your warfarin clinic's advice. Do not stop or change medicine on your own.	Authoritative guidance ^{19 20}
Kidney disease, especially on dialysis, or taking ACE inhibitors, ARBs or potassium-sparing diuretics	Ask a clinician about potassium-rich foods such as Brussels sprouts.	Authoritative guidance ¹⁷
A thyroid condition	A 2024 review found brassica vegetables eaten as food do not harm thyroid function, especially with adequate iodine. Ask your clinician about your own diet and iodine intake.	Systematic review ⁴
Known allergy to Brussels sprouts or other cabbage-family vegetables	Avoid it and ask an allergist. Call emergency services for trouble breathing or swelling of the face or throat. No source read describes Brussels sprout allergy specifically.	Not established
Pregnancy, young children, older age or weakened immunity (foodborne illness)	The FDA says these groups can be especially vulnerable to foodborne illness. Wash produce under running water, and cook it thoroughly, which the FDA says kills harmful bacteria.	Authoritative guidance ¹⁴

Overdose, product quality and regulators

Summary. No toxicity from Brussels sprouts as ordinary food was found in the sources read. The cautions are specific to people with certain medicines or conditions.

Animal. Not reviewed.

Human doses studied. Feeding trials gave healthy volunteers 300 to 400 g of Brussels sprouts a day for one to three weeks; the abstracts report lab markers and warfarin clearance, and do not describe harm.

Overdose response. Not found.

Genotoxicity. Not researched.

Fresh produce can carry germs from soil, water or handling. The FDA says washing reduces but does not eliminate bacteria and cooking thoroughly kills them. Pesticide residues, heavy metals and nitrate in Brussels sprouts were not researched.

Food safety handling. The FDA says to choose produce that is not bruised or damaged, keep cut or packaged produce at 40 F (4 C) or below, wash all produce thoroughly under running water, not to use soap, detergent or commercial produce wash, that washing reduces but will not eliminate bacteria, and that cooking produce thoroughly kills harmful bacteria. ¹⁴

Not the same as seed sprouts. The FDA warning about raw or lightly cooked sprouts is about sprouts grown from seeds and beans (such as alfalfa and mung bean) in warm, humid conditions. Brussels sprouts are the small buds of a cabbage-family plant, not seed sprouts. This is our reading; the FDA page does not mention Brussels sprouts. ^{14 15}

Body	Action	Date
NHS (UK) (United Kingdom)	Warfarin page: foods high in vitamin K, such as broccoli, spinach and other green leafy vegetables, can affect how warfarin works; you can still eat them but ask your warfarin clinic; do not take vitamin K supplements. Brussels sprouts are not named. source	2026-02-24
MedlinePlus (US National Library of Medicine) (United States)	Vitamin K page: lists Brussels sprouts, broccoli, cauliflower and cabbage as food sources; if you take warfarin you may need to eat the same amount of vitamin K foods every day; sudden changes can change the medicine's effect. source	2025-01-21
MedlinePlus (US National Library of Medicine) (United States)	Potassium page: people with kidney problems, particularly on dialysis, should not eat too many potassium-rich foods; ACE inhibitors, ARBs and potassium-sparing diuretics are named among causes of high blood potassium. Brussels sprouts are not named. source	2026-04-30
FDA (United States) (United States)	Selecting and Serving Produce Safely: wash produce under running water without soap; washing reduces but does not eliminate bacteria; cooking thoroughly kills harmful bacteria; children, older adults, pregnant women and people with weakened immune systems are especially vulnerable to foodborne illness. source

When to get medical help

Trouble breathing, swelling of the lips, face or throat, or widespread hives after eating Brussels sprouts
Signs of serious bleeding while taking warfarin, such as blood in urine or stool, unexplained bruising or nosebleeds (NHS lists these as symptoms of serious bleeding)
Vomiting, diarrhoea, stomach pain or fever after eating raw or undercooked produce (the FDA lists vomiting, diarrhea, abdominal pain, fever, headache and body ache as symptoms of foodborne illness)

Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.

General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.

Frequently asked questions

What are Brussels sprouts good for?

They are a rich source of vitamin C and vitamin K and a source of fibre, folate and potassium. Health claims beyond that come from studies of cruciferous vegetables in general, which are mostly observational.

^{21 18 19}

Are Brussels sprouts safe with warfarin?

MedlinePlus lists Brussels sprouts as a vitamin K food and says to keep your intake the same day to day, because sudden changes can alter warfarin's effect. The NHS says you can still eat vitamin K foods but should ask your warfarin clinic. Do not change your medicine on your own.

^{19 20}

Do Brussels sprouts affect the thyroid?

A 2024 systematic review of 123 studies concluded that brassica vegetables eaten as part of the diet, particularly with adequate iodine, pose no adverse effects on thyroid function. If you have a thyroid condition, ask your clinician.

⁴

Do Brussels sprouts cause gas?

Some people think so: in a UK survey of 516 adults, 23% said Brussels sprouts cause flatulence, though gas did not worry most respondents. This is perception, not a measured effect.

¹¹

Do Brussels sprouts prevent cancer?

Not shown. Observational studies link more cruciferous vegetables to lower colon cancer risk (odds ratio 0.80), but they cannot show cause, and the Linus Pauling Institute calls the evidence that isothiocyanates from these vegetables lower cancer risk insufficient.

^{6 16}

Are Brussels sprouts good for the heart?

Observational studies link more cruciferous vegetables, and fruit and vegetables generally, to less heart disease. One tiny trial of 18 people found a 2.5 mm Hg lower systolic pressure on a cruciferous diet. Neither is about Brussels sprouts alone.

^{1 2}

Do Brussels sprouts help blood sugar or diabetes?

Possibly a little, but evidence is weak. Four cohort studies link cruciferous vegetables to lower diabetes risk (RR 0.84), and one 18-person trial found slightly lower after-meal glucose. The authors say the clinical impact is uncertain.

^{5 3}

Does cooking change Brussels sprouts?

Cooking inactivates myrosinase, the enzyme that turns glucosinolates into sulforaphane-type compounds; light steaming for under 5 minutes keeps some (Linus Pauling Institute). A lab study found sous-vide cooking lost more glucosinolates than conventional cooking. No reliable figure for vitamin C loss in sprouts was found.

^{16 10}

Is it safe to eat Brussels sprouts raw?

The FDA says washing produce under running water reduces but does not eliminate bacteria, and that cooking thoroughly kills harmful bacteria. The FDA's special warning about raw sprouts is about seed sprouts such as alfalfa and mung bean; Brussels sprouts are cabbage-family buds, not seed sprouts (our reading).

¹⁴

Are Brussels sprouts safe in pregnancy?

No special caution for the vegetable was found in the sources read. The FDA says pregnant women are especially vulnerable to foodborne illness, so wash produce under running water and cook it thoroughly. Ask your doctor.

¹⁴

Can I be allergic to Brussels sprouts?

Any food can cause a reaction, but no source read describes allergy to Brussels sprouts specifically. For trouble breathing or swelling of the face or throat, call emergency services.

Is sulforaphane from supplements the same as eating Brussels sprouts?

No. Most work on glucosinolates and sulforaphane is lab or animal research or uses concentrated products. Results for those do not carry over to eating the vegetable, and the Linus Pauling Institute describes the human cancer evidence as insufficient.

¹⁶

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Editorial transparency

Written by: AlternativeMed editorial team. Research compiled with AI assistance, then checked against the sources listed.
Medical review: None. This page has not been reviewed by a physician or pharmacist.
First published: 2026-10-26
Last substantive update: 2026-10-26
How we research: We started from our existing Brussels sprouts summary, re-checked nutrition at USDA FoodData Central, read the health agency pages (NHS, MedlinePlus, FDA) and the Linus Pauling Institute, and searched PubMed for reviews, trials and surveys. Only abstracts were read for studies. Items we could not verify are flagged in the research gaps.
How we rate evidence: See "How we rate evidence" in the Evidence tab.
Independence: No product is promoted on this page. No affiliate links are shown.

Sources 21

Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.

Aune D, Giovannucci E, Boffetta P, et al.. Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality-a systematic review and dose-response meta-analysis of prospective studies.. Int J Epidemiol. 2017. PMID 28338764. DOI 10.1093/ije/dyw319. (abstract)
Connolly EL, Liu AH, Radavelli-Bagatini S, et al.. Cruciferous vegetables lower blood pressure in adults with mildly elevated blood pressure in a randomized, controlled, crossover trial: the VEgetableS for vaScular hEaLth (VESSEL) study.. BMC Med. 2024. PMID 39218859. DOI 10.1186/s12916-024-03577-8. (abstract)
Connolly EL, Liu AH, Woodman RJ, et al.. Cruciferous vegetables improve glycaemic control compared to root/squash vegetables in a randomized, controlled, crossover trial: The VEgetableS for vaScular hEaLth (VESSEL) study.. Diabetes Obes Metab. 2025. PMID 40375391. DOI 10.1111/dom.16467. (abstract)
Galanty A, Grudzinska M, Pazdziora W, et al.. Do Brassica Vegetables Affect Thyroid Function?-A Comprehensive Systematic Review.. Int J Mol Sci. 2024. PMID 38612798. DOI 10.3390/ijms25073988. (abstract)
Jia X, Zhong L, Song Y, et al.. Consumption of citrus and cruciferous vegetables with incident type 2 diabetes mellitus based on a meta-analysis of prospective study.. Prim Care Diabetes. 2016. PMID 26778708. DOI 10.1016/j.pcd.2015.12.004. (abstract)
Lai B, Li Z, Li J.. Cruciferous vegetables intake and risk of colon cancer: a dose-response meta-analysis.. BMC Gastroenterol. 2025. PMID 40790161. DOI 10.1186/s12876-025-04163-9. (abstract)
Nanjee MN, Verhagen H, van Poppel G, et al.. Do dietary phytochemicals with cytochrome P-450 enzyme-inducing activity increase high-density-lipoprotein concentrations in humans?. Am J Clin Nutr. 1996. PMID 8901789. DOI 10.1093/ajcn/64.5.706. (abstract)
Navarro SL, Schwarz Y, Song X, et al.. Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults.. J Nutr. 2014. PMID 25165394. DOI 10.3945/jn.114.197434. (abstract)
Ovesen L, Lyduch S, Idorn ML.. The effect of a diet rich in brussels sprouts on warfarin pharmacokinetics.. Eur J Clin Pharmacol. 1988. PMID 3203715. DOI 10.1007/BF01046714. (abstract)
Sadowska-Rociek A, Doniec J, Kusznierewicz B, et al.. The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans.. Foods. 2024. PMID 39335916. DOI 10.3390/foods13182988. (abstract)
Thomson CL, Garcia AL, Edwards CA.. Prevalence of gastrointestinal symptoms in the UK adult population and perceived effects of foods.. Eur J Nutr. 2025. PMID 40848137. DOI 10.1007/s00394-025-03780-0. (abstract)
Verhagen H, Poulsen HE, Loft S, et al.. Reduction of oxidative DNA-damage in humans by brussels sprouts.. Carcinogenesis. 1995. PMID 7728983. DOI 10.1093/carcin/16.4.969. (abstract)
Verhagen H, de Vries A, Nijhoff WA, et al.. Effect of Brussels sprouts on oxidative DNA-damage in man.. Cancer Lett. 1997. PMID 9103270. DOI 10.1016/s0304-3835(97)04641-7. (abstract)
. FDA: Selecting and Serving Produce Safely. . . (full-text)
. GBIF Backbone: Brassica oleracea L. (usageKey 3042845). . . (full-text)
. Linus Pauling Institute: Isothiocyanates. . . (full-text)
. MedlinePlus: Potassium in diet. . . (full-text)
. MedlinePlus: Vitamin C. . . (full-text)
. MedlinePlus: Vitamin K. . . (full-text)
. NHS: Warfarin. . . (full-text)
. USDA FoodData Central: Brussels sprouts, raw (FDC 170383). . . (full-text)

Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.