Beverages · Drink
Energy Drinks
Caffeinated soft drink (not a species) · also called Energy drink, energy beverage, bebida energética
Energy drinks are canned soft drinks that combine caffeine with sugar, added B vitamins and often taurine. In short tests they improved strength and endurance results, but one drink also raised blood pressure for hours in healthy adults. Medical experts advise against them for children and teens. The main cautions are heart and blood pressure, pregnancy, sleep and mixing with alcohol.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Energy Drinks
Energy drinks are caffeinated soft drinks with sugar, added B vitamins and often taurine. They are a drink, not a remedy: the benefit we can document is a small gain in short performance tests, while documented risks include a short rise in blood pressure, worse sleep and official advice against use by children and teens.
What is in an energy drink
An energy drink is a canned or bottled soft drink sold for a lift. The main ingredients named in the sources we read are caffeine, sugar, added B vitamins and often taurine. A Spanish expert group assumed typical products have about 32 mg of caffeine per 100 mL and about 4,000 mg of taurine per litre.
USDA data for a sugar-sweetened energy drink (older formula, a branded item), per 100 g: 43 kcal, 10.22 g sugars, 29 mg caffeine, 39 mg sodium and 19 mg magnesium. One 8.4 fl oz can (258 g) has about 111 kcal, 26.4 g sugars and 75 mg caffeine. A second USDA item has 33 mg caffeine per 100 g, so about 79 mg in a 240 g serving. Modern cans and sugar-free versions differ.
How much caffeine is in one
It varies a lot. The FDA table lists 41 to 246 mg in 12 fl oz of energy drink and 113 to 247 mg in 12 fl oz of regular brewed coffee. Read the label for caffeine per can.
The FDA has cited 400 mg a day as an amount not generally associated with negative effects for most adults, from all sources together, and notes wide differences in sensitivity. The NHS limit in pregnancy is 200 mg a day.
Added B vitamins
The USDA item has very high B-vitamin values: about 5.59 mg vitamin B-6 and 5.08 mcg vitamin B-12 in a 258 g can. They come from added vitamins. We read no study showing that these extra vitamins give more energy to people who are not short of them.
What the research shows
Performance: a pooled analysis of 34 short studies found one drink improved strength and endurance, endurance tests, jumping and sport-specific actions in tests, with effect sizes of about 0.3 to 0.5. It did not clearly improve sprinting. The gain was linked to the taurine amount but not to the caffeine amount across studies. An umbrella review of 21 meta-analyses found caffeine alone also improves exercise performance on many tasks, so caffeine may explain part of it.
Blood pressure and heart: in 17 randomised trials in healthy adults one drink raised systolic pressure by about 4.7 mmHg at 60 to 80 minutes (moderate-quality evidence) and diastolic pressure at 120 minutes. Heart rate and QT/QTc did not change significantly in that analysis, but a 2025 review of 37 studies reported QTc prolongation in many, so the rhythm question is unsettled.
Young people: a 2024 review of 57 studies linked energy drinks in people up to 21 with substance use, short sleep, psychological distress and dental decay. The authors say it does not show cause. Sleep: a review found caffeine typically delays sleep and shortens it. Everyday energy and focus: we found no study that tested energy drinks for these.
Drink versus ingredients and supplements
The blood pressure and young-people results are for energy drinks. The sleep and caffeine-performance results are for caffeine in general. Animal results for taurine and caffeine in the teenage brain are not trials in people. Pure caffeine powder and vitamin supplements are different products.
At a glance
Traditional uses history, not proof
- Drunk for a quick lift before sport, study or work
- Long use as a drink is not proof that it helps any condition
Studied for research
- Physical performance in short tests, low certainty
- Everyday energy and focus, insufficient evidence
- Added B vitamins, high certainty they are in the drink, no benefit shown
- Blood pressure, a short-term rise (moderate certainty), a caution
- Heart rhythm, mixed
- Sleep, a worsening from caffeine (low certainty for these drinks)
- Children and young people, low certainty (observational), with official advice against
Main compounds
- Caffeine
- Sugars
- Taurine
- B vitamins (B2, B3, B6, B12)
- D-glucuronolactone
- Magnesium and sodium
Common forms
- Sugar-sweetened cans (USDA items read)
- Sugar-free versions, energy shots and powders were not read
- Pure caffeine powders are a different and far more dangerous product
Research links: 2024 trials review: energy drinks and blood pressure · 2017 review: energy drinks and physical performance · 2024 review: energy drinks in children and young people · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Energy drink (a manufactured soft drink)
- Common names
- Energy drink (English); Energy shot (small bottle, different product) (English); Bebida energética (Spanish)
- Family or group
- Beverages: caffeinated soft drinks. The nutrient summary files it under caffeinated beverages.
- Harvest and processing
- Energy drinks are manufactured drinks. Typical ingredients named in the sources read are caffeine, sugar, B vitamins and taurine; the Spanish risk assessment also names D-glucuronolactone. Recipes differ by product.
- Look-alikes and adulterants
- Name: Coffee, tea and cola; Note: Other caffeinated drinks. The FDA lists 113 to 247 mg of caffeine in 12 fl oz of regular brewed coffee, 23 to 83 mg in a caffeinated soft drink and 41 to 246 mg in an energy drink.; Name: Sports drinks; Note: A different product. The AAP says the terms sports drink and energy drink should not be used interchangeably.; Name: Energy shots and caffeine powders; Note: Small or concentrated products; pure caffeine powders are far more dangerous (FDA).
Photographs
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 |
|---|---|---|---|---|
| Caffeine | methylxanthine | Added or from guarana or other sources (not specified in sources read) USDA: 29 mg and 33 mg per 100 g in the two items; FDA: 41 to 246 mg per 12 fl oz | The main stimulant in the drink. In the sources read it raises alertness in tests and delays sleep. 15 14 12 | Human data |
| Sugars | carbohydrate | Added USDA: 10.22 g and 10.93 g total sugars per 100 g | Calories and added sugar; WHO limits free sugars. 15 14 16 | Database |
| Taurine | amino sulfonic acid | Added About 4,000 mg per litre in typical products (Spanish risk assessment); USDA does not list it | In the pooled performance analysis the gain was linked to the taurine amount; animal studies raise questions for teenagers. 9 10 4 | Human and animal |
| B vitamins (B2, B3, B6, B12) | vitamins | Added USDA item 173210 per 100 g: B-6 2.167 mg, B-12 1.97 mcg, niacin 9.827 mg, riboflavin 0.103 mg | Added vitamins; no source read shows extra energy in people who are not deficient. 15 14 | Database |
| D-glucuronolactone | sugar acid lactone | Added About 2,400 mg per litre in typical products (Spanish risk assessment) | Not studied for benefit in the sources read; the risk assessment found some modelled risks. 9 | Modelling |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Adenosine receptors and sleep | Genes of adenosine signalling (named in the abstract, not specified) | The sleep review notes that caffeine affects sleep and that gene variants in adenosine signalling contribute to individual sensitivity. 2 | Human data |
| Blood pressure and cardiac output | Not specified in the sources read | Energy drinks raised systolic and diastolic pressure and cardiac output after one drink in healthy adults. Which ingredient is responsible was not tested. 6 | Human data |
| Taurine and caffeine in the developing brain | Not specified | A review of mostly animal studies suggests age matters for toxicity of both ingredients. 4 | Animal research |
Absorption, metabolism and elimination
- Absorption
- Not found in the sources read.
- Distribution
- Not found.
- Metabolism
- The FDA says people differ widely in how fast they clear caffeine.
- Elimination
- Not found.
- Bioavailability
- Not established.
Isolated compounds versus whole extracts
This page is about the drink as sold. Results for caffeine alone (performance umbrella review, sleep review) are not results for energy drinks. Results for pure caffeine powder are about a different and far more dangerous product. Supplements with taurine or B vitamins are not the drink.
Nutritional composition
Nutrition from USDA FoodData Central (SR Legacy, April 2018 release; values read 2026-10-26 from the saved USDA copy in the repository). These are older formulas for branded products; modern cans differ. Sugar-sweetened energy drink (FDC 173210), per 100 g: 43 kcal, 10.22 g total sugars, 0.46 g protein, 0 g fat, 29 mg caffeine, 39 mg sodium, 19 mg magnesium, 0.103 mg riboflavin, 9.827 mg niacin, 2.167 mg vitamin B-6 and 1.97 mcg vitamin B-12. One can (8.4 fl oz, 258 g, the 100 g values multiplied by 2.58) holds about 111 kcal, 26.4 g sugars, 75 mg caffeine, 101 mg sodium, 49 mg magnesium, 0.27 mg riboflavin, 25.4 mg niacin, 5.59 mg vitamin B-6 and 5.08 mcg vitamin B-12. USDA also lists 12 fl oz (369 g) and 16 fl oz (492 g) servings. A second item (FDC 171935, a 240 g serving): per 100 g 47 kcal, 10.93 g sugars, 33 mg caffeine and 77 mg sodium, so about 113 kcal, 26 g sugars and 79 mg caffeine per serving. The very high vitamin values come from added vitamins. USDA does not list taurine. Sugar-free versions were not read.
1 high certainty2 mixed findings3 low certainty3 not enough evidence
What was looked at
The 9 benefits and uses checked for Energy Drinks, each with how strong the evidence is. Tap one to open it.
- Physical performance in tests (short term)Low certainty
- Everyday energy, focus and alertnessNot enough evidence
- Added B vitamins and magnesium (what the drink contains)High certainty
- Heart rhythm (QT interval): a cautionMixed findings
- Sleep (caffeine in general)Low certainty
- Children and young peopleLow certainty
- Mixing with alcoholMixed findings
- Taurine, caffeine and the developing brain (animal studies)Not enough evidence
- Reports of harm (not rates)Not enough evidence
Lab markers tracked in the studies
Systolic blood pressureResting heart rateQTc interval
What is Energy Drinks good for?
The main studied uses and how strong the human evidence is for each. Several entries are cautions, not benefits. Most results are for single drinks tested over hours, not for regular use.
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.
Physical performance in tests (short term)
Low certaintyA pooled analysis of 34 studies found that one energy drink improved muscle strength and endurance, endurance tests, jumping and sport-specific actions in tests. It did not clearly improve sprinting.
2 studiesSugar-sweetened and caffeine-containing drinks as sold, in single dos…
Studies, doses and limits
What the trials found
The 34 studies were acute: one drink, then a performance test within hours. They were tests in people doing sport or exercise, not everyday health.
Results
Small to moderate gains in test performance right after a drink. Not evidence of lasting benefit.
Effect sizes as reported
Effect sizes 0.49 (strength and endurance), 0.53 (endurance tests), 0.29 (jumping), 0.51 (sport-specific actions); sprinting 0.14, not significant.
Why this rating
Low because the results are short-term test scores, the studies used different ingredient amounts and tests, and funding was not stated in the abstract. An umbrella review of 21 meta-analyses found caffeine on its own improves exercise performance on many tasks (moderate-quality evidence), so caffeine may explain part of any effect.
Form and dose studied
Sugar-sweetened and caffeine-containing drinks as sold, in single doses.
Who was studied
Mostly young adults in sport and exercise tests.
Limits
Acute tests only. Results for caffeine by itself are not the same as results for a mixed drink. No long-term trial was read.
Why researchers looked
People drink them before sport or work hoping for more stamina or alertness.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Association across trials
Caffeine is the main stimulant in the drink. In the pooled analysis the gain was linked to the taurine amount but not to the caffeine amount; this is an association across studies and does not show that taurine caused it.
A proposed mechanism does not show that the effect happens in people.
The same drinks raise blood pressure for hours; see the Safety tab.
Everyday energy, focus and alertness
Not enough evidenceNo source we read tested energy drinks for everyday tiredness, focus or memory, apart from the test results above.
0 studiesNot applicable.
Studies, doses and limits
What the trials found
No trial of everyday energy or concentration in daily life was read.
Results
Not enough evidence.
Why this rating
Insufficient: no study read measured everyday energy, mood or concentration with an energy drink. Caffeine also delays sleep (see the other Benefits tab entries), which can work against energy the next day.
Limits
This is a gap, not evidence of no effect.
Why researchers looked
The drinks are sold for energy and focus.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Background
Caffeine blocks tiredness signals for a while. This is general background and was not tested in the sources read for everyday use.
A proposed mechanism does not show that the effect happens in people.
See Safety.
Added B vitamins and magnesium (what the drink contains)
High certaintyUSDA lists very high B-vitamin values in sugar-sweetened energy drinks, which come from added vitamins. We read no study showing that these extra vitamins give more energy to people who are not short of them.
2 studiesA branded sugar-sweetened can; formulas change.
Studies, doses and limits
What the trials found
No trial was read showing extra B vitamins from an energy drink raise energy in people who already get enough.
Results
The drink is a source of added B vitamins on paper. Whether that helps anyone was not shown.
Effect sizes as reported
USDA item 173210 per can (258 g): about 5.59 mg vitamin B-6, 5.08 mcg vitamin B-12, 25.4 mg niacin, 0.27 mg riboflavin, 49 mg magnesium. A second USDA item lists 1.01 mg B-6 and 2.57 mcg B-12 per 100 g.
Why this rating
High that the drinks contain these nutrients (USDA data, older formulas). Not tested as a way to get energy or fix a shortfall.
Form and dose studied
A branded sugar-sweetened can; formulas change.
Who was studied
General adult diet.
Limits
Nutrient facts, not trials. Modern cans and sugar-free versions differ.
Why researchers looked
B vitamins help the body release energy from food, so labels often use them in energy claims.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Nutrient database
These are nutrient amounts taken from USDA tables.
A proposed mechanism does not show that the effect happens in people.
Sugar, caffeine and other points are on the Safety tab.
Heart rhythm (QT interval): a caution
Mixed findingsTwo reviews disagree. A 2025 review found QTc prolongation in many studies. A 2024 pooled analysis of randomised trials found no significant QT/QTc change after one drink.
2 studiesDrinks as sold.
Studies, doses and limits
What the trials found
The 2025 review covered 37 studies and 1,597 people aged 13 and over (mean age 22.6). The 2024 analysis covered randomised trials in healthy adults.
Results
Not settled. The reviews differ, and healthy young adults dominate both.
Effect sizes as reported
The 2025 review reports QTc prolongation in 63.2% (of studies, apparently); the trial analysis found no significant QT/QTc change.
Why this rating
Mixed: two systematic reviews give different answers, and neither covers people with heart rhythm problems well.
Form and dose studied
Drinks as sold.
Who was studied
Mostly young, healthy adults.
Limits
The 2025 abstract does not make clear what the percentages are of. No long-term study read.
Why researchers looked
The QT interval is part of the heart trace (ECG). A long QT can come before a dangerous rhythm.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Background
Caffeine and other stimulants act on the heart and blood vessels. How much each ingredient matters here was not clear in the sources read.
A proposed mechanism does not show that the effect happens in people.
If you have a heart rhythm problem or take a medicine for one, ask your clinician before using these drinks.
Sleep (caffeine in general)
Low certaintyA systematic review found caffeine typically makes it take longer to fall asleep, shortens sleep and lowers sleep quality, with effects that depend on dose and timing.
2 studiesCaffeine from coffee, capsules and other sources.
Studies, doses and limits
What the trials found
Coffee and caffeine studies, mostly in Western adult men. Energy drinks were not the main subject.
Results
Caffeine worsened several sleep measures. A European modelling study also suggested volume limits to avoid sleep disturbance from energy drinks.
Effect sizes as reported
No pooled numbers in the abstract.
Why this rating
Low for energy drinks: the evidence is for caffeine in general and the trials were not of energy drinks. For caffeine itself it is stronger.
Form and dose studied
Caffeine from coffee, capsules and other sources.
Who was studied
Mostly male adults in Western countries; older adults may be more sensitive.
Limits
Indirect for energy drinks. Longer-term health effects of the sleep changes were not shown.
Why researchers looked
Caffeine is the main active ingredient of the drinks and is known to affect sleep.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Review of trials
Caffeine blocks the receptors that build up sleep pressure (adenosine). The review notes gene differences in this pathway.
A proposed mechanism does not show that the effect happens in people.
See Safety for FDA caffeine signs.
Children and young people
Low certaintyA 2024 review of 57 studies linked energy drinks in people up to age 21 with substance use, short sleep, poor mood and school results, dental decay and other outcomes. The authors say it does not show cause.
2 studiesEnergy drinks as consumed by young people.
Studies, doses and limits
What the trials found
Observational studies of children and young people up to 21; weak studies were removed.
Results
A strong and consistent set of associations, with cause unproven. The American Academy of Pediatrics said in 2011 that caffeine and other stimulants have no place in the diet of children and adolescents.
Effect sizes as reported
No pooled numbers in the abstract.
Why this rating
Low: mostly observational. The consistency of the warning and the official advice are why the caution stands even though cause is not proven.
Form and dose studied
Energy drinks as consumed by young people.
Who was studied
Children and young people up to 21.
Limits
Observational, mixed study quality. The AAP report is from 2011.
Why researchers looked
Young people are the biggest marketing target, and caffeine affects them differently from adults.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Observational
Not established. Associations in surveys can reflect differences between young people who do and do not drink them.
A proposed mechanism does not show that the effect happens in people.
See the Safety tab.
Mixing with alcohol
Mixed findingsA 2016 pooled analysis found people who mix alcohol with energy drinks drink more on a typical night than people who drink alcohol only. In the same people, though, total alcohol on mixed nights did not differ from alcohol-only nights.
1 studiesAlcohol mixed with energy drinks.
Studies, doses and limits
What the trials found
Fourteen survey-based studies.
Results
Mixed: higher alcohol in the group comparison, no difference within people.
Effect sizes as reported
Between groups ES 0.536 (0.349 to 0.724); within people ES -0.052 (-0.192 to 0.088).
Why this rating
Mixed: the two kinds of comparison disagree, and the studies measure alcohol amount only.
Form and dose studied
Alcohol mixed with energy drinks.
Who was studied
Adults and young adults in surveys.
Limits
Alcohol amount only; other effects of the mixture were not measured.
Why researchers looked
Energy drinks are often mixed with alcohol, and people asked whether this leads to drinking more.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Not established
Not established in the sources read. The claim that caffeine masks drunkenness was not verified and is not made here.
A proposed mechanism does not show that the effect happens in people.
See Safety.
Taurine, caffeine and the developing brain (animal studies)
Not enough evidenceA review of mostly animal studies concluded teenagers are unlikely to benefit from caffeine or taurine supplements and may be harmed by chronic high doses. This is animal work, not a trial in people.
1 studiesPure compounds in animals.
Studies, doses and limits
Results
Animal and lab evidence only.
Why this rating
Insufficient for people: the review summarises animal studies, mostly in males.
Form and dose studied
Pure compounds in animals.
Who was studied
Animals.
Limits
Not tested in teenagers.
Why researchers looked
Teenagers are the main young consumers and the adolescent brain is still developing.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Animal research
Animal experiments with caffeine and taurine, by age.
A proposed mechanism does not show that the effect happens in people.
See the Safety tab.
Reports of harm (not rates)
Not enough evidenceA study of US reports (2008 to 2015) found serious and life-threatening events were reported after caffeinated energy drinks. Reports cannot show how common the events are or that the drink caused them.
1 studiesEnergy drinks as consumed.
Studies, doses and limits
What the trials found
Cross-sectional look at FDA reports and poison centre calls.
Results
Events are reported; cause and rate are unknown.
Effect sizes as reported
No rates in the abstract.
Why this rating
Insufficient to say how risky the drinks are, because reports have no denominator.
Form and dose studied
Energy drinks as consumed.
Who was studied
All ages.
Limits
Voluntary reports; authors include FDA staff.
Why researchers looked
Regulators watch products after sale.
Traditional use
Energy drinks are canned or bottled soft drinks sold for a quick lift. Their long use as a drink is not proof that they help any condition.
Proposed mechanism Surveillance
Not applicable.
A proposed mechanism does not show that the effect happens in people.
See the Safety tab.
Connections to the rest of health
How Energy Drinks 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
A. Wellness goals
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Peak Performance | Low certainty | Physical performance in tests (short term): A pooled analysis of 34 studies found that one energy drink improved muscle strength and endurance, endurance tests, jumping and sport-specific actions in tests. It did not clearly improve sprinting. | 10 5 | |
| Endurance Support | Low certainty | Physical performance in tests (short term): A pooled analysis of 34 studies found that one energy drink improved muscle strength and endurance, endurance tests, jumping and sport-specific actions in tests. It did not clearly improve sprinting. | 10 5 | |
| Physical Stamina | Low certainty | Physical performance in tests (short term): A pooled analysis of 34 studies found that one energy drink improved muscle strength and endurance, endurance tests, jumping and sport-specific actions in tests. It did not clearly improve sprinting. | 10 5 | |
| Energy Boost | Not enough evidence | Everyday energy, focus and alertness: No source we read tested energy drinks for everyday tiredness, focus or memory, apart from the test results above. | ||
| Reduce Fatigue | High certainty | Added B vitamins and magnesium (what the drink contains): USDA lists very high B-vitamin values in sugar-sweetened energy drinks, which come from added vitamins. We read no study showing that these extra vitamins give more energy to people who are not short of them. | 15 14 | |
| Heart Health | Mixed findings | Heart rhythm (QT interval): a caution: Two reviews disagree. A 2025 review found QTc prolongation in many studies. A 2024 pooled analysis of randomised trials found no significant QT/QTc change after one drink. | 7 6 | |
| Sleep Quality | Low certainty | Sleep (caffeine in general): A systematic review found caffeine typically makes it take longer to fall asleep, shortens sleep and lowers sleep quality, with effects that depend on dose and timing. | 2 9 | |
| Preventive Wellness | Low certainty | Children and young people: A 2024 review of 57 studies linked energy drinks in people up to age 21 with substance use, short sleep, poor mood and school results, dental decay and other outcomes. The authors say it does not show cause. | 1 3 | |
| Preventive Wellness | Mixed findings | Mixing with alcohol: A 2016 pooled analysis found people who mix alcohol with energy drinks drink more on a typical night than people who drink alcohol only. In the same people, though, total alcohol on mixed nights did not differ from alcohol-only nights. | 11 | |
| Brain Health | Not enough evidence | Taurine, caffeine and the developing brain (animal studies): A review of mostly animal studies concluded teenagers are unlikely to benefit from caffeine or taurine supplements and may be harmed by chronic high doses. This is animal work, not a trial in people. | 4 | |
| Preventive Wellness | Not enough evidence | Reports of harm (not rates): A study of US reports (2008 to 2015) found serious and life-threatening events were reported after caffeinated energy drinks. Reports cannot show how common the events are or that the drink caused them. | 8 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Musculoskeletal System | Biological association | Low certainty | Studied for: Physical performance in tests (short term) | 10 5 |
| Sleep Recovery | Biological association | Not enough evidence | Studied for: Everyday energy, focus and alertness Studied for: Sleep (caffeine in general) | 2 9 |
| Metabolism Weight | Biological association | High certainty | Studied for: Added B vitamins and magnesium (what the drink contains) | 15 14 |
| Cardiovascular System | Biological association | Mixed findings | Studied for: Heart rhythm (QT interval): a caution Studied for: Reports of harm (not rates) | 7 6 8 |
| Nervous System | Biological association | Low certainty | Studied for: Children and young people Studied for: Mixing with alcohol | 1 3 11 4 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| High blood pressure | Adverse effect or risk | Documented risk | Raised blood pressure for hours after one drink in a pooled analysis of 17 trials. Raised blood pressure for hours after one drink in 17 trials. Preparation or compound: Energy drinks as sold |
6 |
| Heart rhythm problems | Adverse effect or risk | Mixed findings | QTc prolongation in many studies in a 2025 review; no significant change in the trial analysis. Preparation or compound: Energy drinks as sold |
7 6 |
| Poor sleep | Adverse effect or risk | Documented risk | Caffeine typically delayed sleep and cut sleep time in a systematic review. Caffeine typically delayed sleep and shortened it. Preparation or compound: Caffeine |
2 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Systolic blood pressure | Biological association | Moderate certainty | Measured in trials: raised. A lab change is not the same as a health benefit. | 6 |
| Resting heart rate | Biological association | Moderate certainty | Measured in trials: no significant change. A lab change is not the same as a health benefit. | 6 7 |
| QTc interval | Biological association | Mixed findings | Measured in trials: mixed. A lab change is not the same as a health benefit. | 6 7 |
K. Biological pathways
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Vitamin B-12 | Preliminary mechanism | Lab | Added to the drink; USDA lists 1.97 mcg per 100 g in one item. | 15 |
| Caffeine | Preliminary mechanism | Human | Main stimulant; sleep and blood pressure effects read. | 2 6 |
| Taurine | Preliminary mechanism | Human and animal | Added to many products; performance gain linked to taurine amount in one analysis; animal concerns in teenagers. | 10 4 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Caffeine | Biological association | Human | The main stimulant in the drink. In the sources read it raises alertness in tests and delays sleep. Preparation or compound: Added or from guarana or other sources (not specified in sources read) |
15 14 12 |
| Sugars | Biological association | Database | Calories and added sugar; WHO limits free sugars. Preparation or compound: Added |
15 14 16 |
| Taurine | Biological association | Human and animal | In the pooled performance analysis the gain was linked to the taurine amount; animal studies raise questions for teenagers. Preparation or compound: Added |
9 10 4 |
| B vitamins (B2, B3, B6, B12) | Biological association | Database | Added vitamins; no source read shows extra energy in people who are not deficient. Preparation or compound: Added |
15 14 |
| D-glucuronolactone | Biological association | Modelling | Not studied for benefit in the sources read; the risk assessment found some modelled risks. Preparation or compound: Added |
9 |
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 2 lab markers
Tap a number to show only those markers. Counts are markers, not people.
The evidence
The research centre for Energy Drinks. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
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 energy drink summary, re-checked nutrition against saved USDA FoodData Central data, read the FDA, NHS and WHO pages and re-read PubMed abstracts for 11 papers. Only abstracts were read for studies. Items we could not verify are flagged in the research gaps.
Study library: every study we checked 16
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Ajibo 2024 Consumption of energy drinks by children and young people: a systematic review examining evidence of physical effects and consumer attitudes. Public Health · PMID 38228408 · DOI |
Systematic review |
57 studies (January 2016 to July 2022) of children and young people up to age 21; weak studies excluded | Energy drinks Drink as sold Usual intake Observational · vs Lower or no intake |
Many studies found a positive association between energy drink intake and smoking, alcohol use, binge drinking and other substance use. Intake was also linked to short sleep, poor sleep quality, low school performance, psychological distress, ADHD symptoms, depressive and panic behaviours, allergic diseases, insulin resistance, dental caries and tooth wear. The authors say longitudinal studies are needed to show cause. No pooled numbers in the abstract (Not applicable) Methods, limits and fundingOutcomes: Substance use, sleep, mental health, allergic disease, insulin resistance, dental caries and tooth wear Limitations: Mostly observational, so the associations do not show that the drinks caused the outcomes; young people who drink energy drinks may differ in other ways. Funding and conflicts: Funding is not stated in the abstract. Registration: PROSPERO CRD42021255484 Read: abstract |
| Clark 2017 Coffee, caffeine, and sleep: A systematic review of epidemiological studies and randomized controlled trials. Sleep Med Rev · PMID 26899133 · DOI |
Systematic review |
Epidemiological studies and randomised trials of coffee and caffeine; most studies in male adults in Western countries | Coffee and caffeine (not energy drinks specifically) Caffeine as studied Dose and timing effects found Varied · vs Placebo or no caffeine |
Caffeine typically lengthened the time to fall asleep, shortened total sleep time and sleep efficiency, and worsened perceived sleep quality. Deep (slow-wave) sleep was typically reduced. Dose and timing mattered, and older adults may be more sensitive. No pooled numbers in the abstract (Not applicable) Methods, limits and fundingOutcomes: Sleep latency, total sleep time, sleep efficiency, sleep quality, slow-wave sleep Limitations: About caffeine in general, so indirect for energy drinks. Mostly men from Western countries. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| Committee on Nutrition and the Council on Sports Medicine and Fitness 2011 Sports drinks and energy drinks for children and adolescents: are they appropriate? Pediatrics · PMID 21624882 · DOI |
Clinical report |
Children and adolescents | Sports drinks and energy drinks Drink as sold |
The American Academy of Pediatrics report concluded that caffeine and other stimulants in energy drinks have no place in the diet of children and adolescents. It also said frequent or excessive intake of calorie-containing sports drinks can substantially raise the risk of overweight or obesity. Not applicable (Not applicable) Methods, limits and fundingOutcomes: Appropriateness of sports and energy drinks for children and adolescents Limitations: A 2011 clinical report, not a trial. Whether the AAP has since retired or replaced it was not checked. Funding and conflicts: Not applicable (professional society report). Read: abstract |
| Curran 2017 Taurine, caffeine, and energy drinks: Reviewing the risks to the adolescent brain. Birth Defects Res · PMID 29251842 · DOI |
Narrative review animal animal-and-human-review |
Mostly animal studies, mostly male animals | Caffeine and taurine Pure compounds in animal experiments Varied Acute and chronic · vs Varied |
The review says age matters for caffeine and taurine toxicity. It concludes adolescents are not likely to benefit from caffeine or taurine supplementation and may suffer ill effects from chronic intake of high doses. It notes that the aged or diseased brain might benefit. No numbers in the abstract (Not applicable) Methods, limits and fundingOutcomes: Brain effects of caffeine and taurine at different ages Limitations: Evidence is from animals, not from trials in teenagers. Few studies in females. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| Grgic 2020 Wake up and smell the coffee: caffeine supplementation and exercise performance-an umbrella review of 21 published meta-analyses. Br J Sports Med · PMID 30926628 · DOI |
Umbrella review |
11 reviews containing 21 meta-analyses of caffeine and exercise performance; most individual studies were in young men | Caffeine (not energy drinks) Caffeine as studied (capsules, drinks and others) Not given in the abstract Acute · vs Placebo or no caffeine |
Caffeine improved exercise performance on a broad range of tasks. Evidence was mostly moderate quality for endurance, strength and power, and low to very low for other outcomes. The effect was generally larger for aerobic than anaerobic exercise. No pooled numbers in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Aerobic endurance, muscle strength, muscle endurance, power, jumping, exercise speed Limitations: About caffeine, not energy drinks. Mostly young men. Not all analyses gave a definite direction once prediction intervals were considered. Funding and conflicts: Competing interests: none declared. Read: abstract |
| Gualberto 2024 Acute effects of energy drink consumption on cardiovascular parameters in healthy adults: a systematic review and meta-analysis of randomized clinical trials. Nutr Rev · PMID 37695306 · DOI |
Systematic review meta analysis |
17 randomised trials in healthy adults (11 with some risk-of-bias concerns, 6 at high risk of bias) | Energy drinks Drink as sold Single drink Measured at 30 minutes up to 120 minutes after the drink · vs Control drink |
Energy drinks raised systolic and diastolic blood pressure and cardiac output at different times. Resting heart rate and QT/QTc interval did not change significantly. No trial measured endothelial function. Systolic pressure +4.71 mmHg at 60-80 minutes (GRADE moderate); diastolic +4.51 mmHg at 120 minutes (GRADE low); cardiac output +0.43 L at 30-40 minutes (GRADE very low) (Systolic 2.97 to 6.45; diastolic 2.60 to 6.42; cardiac output 0.08 to 0.77) Methods, limits and fundingOutcomes: Systolic and diastolic blood pressure, resting heart rate, cardiac output, endothelial function, QT/QTc interval Limitations: One drink and a few hours of follow-up in healthy adults; the authors ask for caution because few studies could be pooled. Long-term effects were not measured. Funding and conflicts: Funding is not stated in the abstract. Registration: PROSPERO CRD42022295335 Read: abstract |
| Mandato 2025 The Effects of Energy Drinks on the Cardiovascular System: A Systematic Review. Curr Cardiol Rep · PMID 41236610 · DOI |
Systematic review |
1597 37 studies, 1,597 participants aged 13 and over (mean age 22.6); Red Bull and Monster were the most studied brands |
Energy drinks Drink as sold Varied Varied · vs Varied |
The review reports increases in heart rate (60.9%), systolic pressure (53.8%), diastolic pressure (61.5%) and QTc prolongation (63.2%), and other ECG changes in 57.9%. The abstract does not spell out what the percentages are percentages of; they appear to be shares of the studies that measured each outcome. Percentages as above; no pooled effect sizes in the abstract (Not given) Methods, limits and fundingOutcomes: Heart rate, blood pressure, QTc interval and other ECG changes Limitations: A narrative review without pooled numbers in the abstract. Mean age was 22.6, so older adults and people with heart disease are not well represented. The percentages are hard to interpret without the full text, which was not read. Funding and conflicts: The authors declare no competing interests. Read: abstract |
| Markon 2019 Caffeinated energy drinks: adverse event reports to the US Food and Drug Administration and the National Poison Data System, 2008 to 2015. Public Health Nutr · PMID 31317857 · DOI |
Cross sectional reports |
US adverse event reports to FDA (357 single-product cases) and poison centre exposure calls (12,822 single-product cases), 2008 to 2015 | Caffeinated energy drinks Drink as sold 2008 to 2015 |
The FDA reports more often indicated serious symptoms than the poison centre calls, and cited life-threatening events. The authors say both sources help to watch the market after sale. No rates in the abstract (Not applicable) Methods, limits and fundingOutcomes: Reported symptoms and outcomes Limitations: Reports and calls show that events were reported, not how common they are or that the drink caused them. Authors include FDA staff. Funding and conflicts: Authors are from the US FDA and the Center for Science in the Public Interest; no funding statement in the abstract. Read: abstract |
| Rubio 2022 Caffeine, D-glucuronolactone and Taurine Content in Energy Drinks: Exposure and Risk Assessment. Nutrients · PMID 36501132 · DOI |
Modelling risk assessment n/a |
Modelled consumers of 40, 60 and 80 kg body weight (Spanish expert group, European context) | Energy drinks (typical ingredient levels) Drink as sold Scenarios modelled · vs Reference values |
Typical products were taken as 32 mg caffeine per 100 mL, 4,000 mg taurine and 2,400 mg D-glucuronolactone per litre. The model found some risks and suggested volume limits to avoid sleep disturbance, and found taurine intakes above its reference value over 500 mL. The authors call for European limits on ingredients, volume and labelling. Caffeine from the modelled scenarios 80 to 160 mg; taurine 1,000 to 2,000 mg; D-glucuronolactone 600 to 1,200 mg (Not applicable) Methods, limits and fundingOutcomes: Intake of caffeine, taurine and D-glucuronolactone against reference values Limitations: A modelling study, not a trial or an observation of harm. It rests on assumed typical product contents. Funding and conflicts: The authors declare no conflict of interest. Read: abstract |
| Souza 2017 Acute effects of caffeine-containing energy drinks on physical performance: a systematic review and meta-analysis. Eur J Nutr · PMID 27757591 · DOI |
Systematic review meta analysis |
34 studies published 1998 to 2015 (searched to December 2015) of energy drinks and physical performance | Caffeine-containing energy drinks Drink as sold Single doses; amounts varied between studies Acute (one dose, tested within hours) · vs Control drinks |
Energy drinks improved muscle strength and endurance, endurance exercise tests, jumping and sport-specific actions, but not sprinting. The gain was linked to the taurine amount in a meta-regression, but not to the caffeine amount. Effect sizes: strength and endurance 0.49; endurance tests 0.53; jumping 0.29; sport-specific actions 0.51; sprinting 0.14 (not significant, p = 0.06). Taurine slope 0.0001 (p = 0.04); caffeine slope 0.0009 (p = 0.21) (Not given in the abstract) Methods, limits and fundingOutcomes: Muscle strength and endurance, endurance tests, jumping, sprinting, sport-specific actions Limitations: Acute results from tests, not everyday health. The studies differed in the amounts of ingredients and the tests used. Participant numbers are not in the abstract. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| Verster 2016 Mixing alcohol with energy drink (AMED) and total alcohol consumption: a systematic review and meta-analysis. Hum Psychopharmacol · PMID 26781580 · DOI |
Systematic review meta analysis |
17780 14 studies: 5,212 people who mix alcohol with energy drinks and 12,568 who drink alcohol only; within-person comparison in 2,871 |
Alcohol mixed with energy drink Drink as sold Usual drinking Observational · vs Alcohol only |
People who mix alcohol with energy drinks drank more alcohol on a typical occasion than people who drink alcohol only. But within the same people, there was no significant difference in total alcohol between mixed and alcohol-only occasions. Between groups ES 0.536; within people ES -0.052 (p = 0.465) (Between groups 0.349 to 0.724; within people -0.192 to 0.088) Methods, limits and fundingOutcomes: Alcohol drunk on a typical drinking occasion Limitations: A 2016 review of surveys. It looks at how much alcohol was drunk, not at other harms of the mixture. The overall n is the sum of the two group sizes. Funding and conflicts: Funding: the abstract lists a non-government research-support type; details are not stated in the abstract. Read: abstract |
| s-fda-caffeine US FDA: Spilling the Beans: How Much Caffeine Is Too Much? · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-nhs-foods-to-avoid NHS: Foods to avoid in pregnancy (caffeine section) · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-usda-fdc-171935 USDA FoodData Central: fortified energy drink item (SR Legacy, FDC 171935) · Source |
Database n/a |
Methods, limits and fundingRead: full-text | ||
| s-usda-fdc-173210 USDA FoodData Central: sugar-sweetened energy drink item (SR Legacy, FDC 173210) · Source |
Database n/a |
Methods, limits and fundingRead: full-text | ||
| s-who-healthy-diet WHO: Healthy diet fact sheet · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text |
What we do not know yet
- No trial of an energy drink on everyday energy, focus or mood was found.
- No long-term study of regular energy drink use and blood pressure or heart health was read.
- Sugar-free energy drinks, shots and modern formulas were not read; the USDA items are older branded formulas.
- Interactions with specific medicines, kidney disease, migraine and epilepsy were not researched. The CDC sugar-sweetened drinks page could not be opened, so no CDC statement is used. Whether the AAP 2011 report has been retired or replaced was not checked.
- Funding of the performance and blood pressure analyses is not stated in their abstracts.
- History and how energy drinks are made were not read from a source.
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".
Other 3
Systolic blood pressure
Raised in trials
The top number of a blood pressure reading: the pressure in the arteries when the heart beats.
Moderate certaintyResults and what it means
Why it was measured
It is the usual measure used in short heart-effect trials of drinks.
Statistical vs. clinical meaning
A short-term rise after one drink in healthy adults. It is a caution, not a benefit. Long-term effects were not measured.
Safety implication
Matters most if you already have high blood pressure or a heart condition; ask your clinician.
| Study | Result | People | Product |
|---|---|---|---|
| 6 | Systolic +4.71 mmHg (95% CI 2.97 to 6.45) at 60 to 80 minutes after the drink (GRADE moderate) | 17 randomised trials in healthy adults; 6 at high risk of bias | One energy drink, then readings from 30 to 120 minutes |
Resting heart rate
No significant change in trials
How many times the heart beats each minute at rest.
Moderate certaintyResults and what it means
Why it was measured
A raised heart rate is one of the signs of too much caffeine.
Statistical vs. clinical meaning
The trial analysis found no significant change in heart rate; a 2025 review reported increases in many studies, so the picture is mixed.
Safety implication
See Safety for FDA signs of too much caffeine.
| Study | Result | People | Product |
|---|---|---|---|
| 6 | Resting heart rate did not change significantly in the pooled trials | Healthy adults in the trials | One energy drink |
QTc interval
Mixed results in trials
The time the heart takes to reset between beats on an ECG, corrected for heart rate.
Mixed findingsResults and what it means
Why it was measured
A long QTc can come before a dangerous heart rhythm.
Statistical vs. clinical meaning
The two reviews disagree, so this is unsettled.
Safety implication
If you have heart rhythm problems or long-QT, ask your clinician.
| Study | Result | People | Product |
|---|---|---|---|
| 6 | QT/QTc interval did not change significantly after one energy drink in the pooled trials | Randomised trials in healthy adults | One energy drink |
| 7 | QTc prolongation reported in 63.2% (of studies, apparently) in a 2025 systematic review | 37 studies, 1,597 people aged 13 and over | Energy drinks, varied |
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
- Children and teens: medical experts advise against energy drinks. The US FDA says medical experts, citing the American Academy of Pediatrics, advise against energy drinks for children and teens because of their sugar and caffeine. The Dietary Guidelines for Americans say caffeinated drinks should be avoided for children under 2. The AAP concluded in its 2011 clinical report that caffeine and other stimulants have no place in the diet of children and adolescents. A 2024 review of 57 studies linked energy drinks in people up to 21 with substance use, poor sleep, psychological distress and dental decay; the authors say cause is not proven. Authoritative guidance 12 3 1
- Heart and blood pressure. In a pooled analysis of 17 randomised trials in healthy adults, one energy drink raised systolic blood pressure by about 4.7 mmHg at 60 to 80 minutes (moderate-quality evidence). A 2025 review reported increased heart rate, blood pressure and QTc prolongation in many studies, while the trial analysis found no significant change in heart rate or QT/QTc. If you have high blood pressure, a heart rhythm problem or take medicine for them, ask your clinician first. Randomised trials and reviews 6 7
- Pregnancy and breastfeeding. The NHS says not to have more than 200 mg of caffeine a day in pregnancy and lists energy drinks as a source, about 80 mg in a 250 ml can. The FDA says to talk to a health care provider about limiting caffeine if you are pregnant, trying to become pregnant or breastfeeding. Authoritative guidance 13 12
- Too much caffeine, and pure caffeine. The FDA lists signs of too much caffeine: faster heart rate, palpitations, high blood pressure, trouble sleeping, anxiety, jitters, upset stomach, nausea and headache. Energy drinks hold 41 to 246 mg per 12 fl oz by the FDA table, so cans vary a lot. The FDA also says pure or highly concentrated caffeine products can cause seizures at around 1,200 mg, under half a teaspoon, and can be fatal. Those products are not energy drinks. Authoritative guidance 12
- Alcohol. A 2016 pooled analysis found people who mix alcohol with energy drinks drink more alcohol on a typical night than people who drink alcohol only, but within the same people total alcohol did not differ between mixed and alcohol-only nights. It did not measure other harms of the mixture. Observational 11
Side effects 5
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Raised blood pressure for hours after a drink Healthy adults, one drink. | Systolic +4.71 mmHg (95% CI 2.97 to 6.45) at 60-80 minutes; diastolic +4.51 mmHg at 120 minutes (low-quality evidence) | moderate in healthy adults; may matter more with heart or blood pressure problems (not tested in those groups in the sources read) Measured only for a few hours; not studied beyond that | Randomised trials 6 |
| Faster heart rate, palpitations, anxiety, jitters, insomnia, upset stomach, nausea and headache from too much caffeine FDA list of signs of too much caffeine from all sources. | Not given | mild to moderate Not described in the source read | Authoritative guidance 12 |
| Delayed sleep, shorter sleep and poorer sleep quality About caffeine in general; dose and timing matter. | Not given | mild to moderate Not described | Systematic review of trials and surveys 2 |
| Serious and life-threatening events reported after caffeinated energy drinks Reports do not show that the drink caused the event. | Cannot be calculated from reports: 357 single-product FDA reports and 12,822 single-product poison centre calls, 2008 to 2015, with no number of drinkers | some reports were serious or life-threatening Not described | Surveillance reports 8 |
| Dental decay and tooth wear in young people Association in a review of observational studies in young people. | Not given | not graded Not described | Observational 1 |
Liver
No liver injury from energy drinks was found in the sources read. A liver-safety source such as LiverTox was not searched.
How often. No frequency was found.
Monitoring. No agency monitoring advice was found.
This is a safety connection. It is not evidence that Energy Drinks supports liver health.
Medicines and supplements 4
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Alcohol recreational | Not established in the sources read. People often mix the two. | A pooled analysis found people who mix them drank more per night than alcohol-only drinkers, but not more on mixed nights than on alcohol-only nights in the same people. | Observational Mixed findings 11 | Ask your doctor or pharmacist if you drink alcohol and use energy drinks. |
| Other caffeine sources (coffee, tea, caffeine pills) dietary | The caffeine adds up. | The FDA says its 400 mg a day figure for most adults counts caffeine from all sources. | Authoritative guidance High certainty 12 | Count all caffeine sources together when you or your clinician think about total caffeine. |
| Medicines the FDA says can raise caffeine sensitivity (not named in the source) prescription | Not named in the source read. | The FDA says some medications, body weight, medical conditions and individual sensitivity can change how much caffeine is too much. It does not list specific medicines. | Authoritative guidance Low certainty 12 | Ask your pharmacist whether caffeine fits with your medicines. |
| Blood pressure or heart rhythm medicines prescription | Not studied in the sources read for energy drinks. | No study of an interaction was found. The trials showed a rise in blood pressure after a drink in healthy adults not taking these medicines. | Not found Not enough evidence 6 | Ask your clinician before using energy drinks if you take these medicines. |
Who should check first 5
| Situation | Advice | Evidence |
|---|---|---|
| Children and teens | Medical experts advise against energy drinks for children and teens (FDA citing the American Academy of Pediatrics). Under age 2, the Dietary Guidelines say avoid caffeinated drinks. | Authoritative guidance 12 3 |
| Pregnancy, trying to conceive or breastfeeding | The NHS limit in pregnancy is 200 mg of caffeine a day from all sources. The FDA says to talk to a provider if pregnant, trying to conceive or breastfeeding. | Authoritative guidance 13 12 |
| High blood pressure, heart rhythm problems, or heart disease | Ask your clinician before using energy drinks; the drinks raised blood pressure for hours in healthy adults, and people with heart conditions were not well studied. | Randomised trials and reviews 6 7 |
| Trouble sleeping, anxiety or caffeine sensitivity | Caffeine can worsen sleep and the FDA lists anxiety and jitters among the signs of too much. Ask your clinician. | Authoritative guidance 12 2 |
| Diabetes or people who watch sugar intake | Sugar-sweetened cans carry about 26 g of sugars each in the USDA item read. Ask your clinician about sugar and your plan. Sugar-free versions were not covered. | Nutrient database 15 16 |
Overdose, product quality and regulators
Summary. The main toxicity issue is caffeine. The FDA says toxic effects such as seizures can occur at around 1,200 mg of caffeine taken quickly, and that pure or highly concentrated caffeine products can cause death. That figure is from pure caffeine, not from cans of energy drink.
Animal. A review of mostly animal studies found chronic high doses of caffeine and taurine may harm the adolescent brain; this is animal evidence.
High dose or long term signals. A Spanish expert group modelled intakes and suggested limits on volume, ingredient levels and labelling; it is a modelling study. Long-term human harm was not measured in the sources read.
Overdose response. Call poison control or emergency services for seizures, fainting, severe chest pain or a very fast heartbeat after caffeine.
Genotoxicity. Not researched.
Contamination and spoilage of cans were not researched. The quality point read is that caffeine content varies a lot between products.
Caffeine content varies. The FDA table lists 41 to 246 mg of caffeine per 12 fl oz of energy drink. The two USDA items list 29 and 33 mg per 100 g. 12 15 14
| Body | Action | Date |
|---|---|---|
| US FDA (United States) | Consumer update: 400 mg a day of caffeine cited as not generally associated with negative effects for most adults; energy drinks 41 to 246 mg per 12 fl oz; medical experts advise against energy drinks for children and teens; talk to a provider if pregnant or breastfeeding. source | 2024-08-28 |
| NHS (United Kingdom) | Pregnancy: do not have more than 200 mg of caffeine a day; energy drinks are listed as a source, about 80 mg in a 250 ml can. source | 2026-06-15 |
| American Academy of Pediatrics (United States) | 2011 clinical report: caffeine and other stimulants in energy drinks have no place in the diet of children and adolescents. source | 2011-06 |
| World Health Organization (International) | Healthy diet fact sheet: limit free sugars to less than 10% of total daily energy; 5% or less may give extra benefit. It does not mention energy drinks. source | 2026-01-26 |
When to get medical help
- Seizures, fainting, chest pain, a very fast or irregular heartbeat, or trouble breathing after drinking energy drinks or taking caffeine: call 911 or your local emergency number
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 is in an energy drink?
How much caffeine is in an energy drink?
It varies. The FDA lists 41 to 246 mg per 12 fl oz of energy drink, against 113 to 247 mg in regular brewed coffee. Check the label for caffeine per can.
Do energy drinks improve sports performance?
Do energy drinks raise blood pressure?
Yes, for a few hours. In 17 randomised trials in healthy adults one drink raised systolic pressure by about 4.7 mmHg at 60 to 80 minutes (moderate-quality evidence). Ask your clinician if you have high blood pressure.
Are energy drinks bad for the heart rhythm?
Are energy drinks safe for children and teens?
Are energy drinks safe in pregnancy or when breastfeeding?
Do the added B vitamins give extra energy?
What about taurine?
Is it safe to mix energy drinks with alcohol?
In a pooled analysis people who mix them drank more on a typical night than people who drink alcohol only, but within the same people there was no difference between mixed and alcohol-only nights. Other harms of the mixture were not measured. Ask your doctor or pharmacist.
Do energy drinks affect sleep?
Caffeine typically delays sleep and shortens it, with effects that depend on dose and timing. That evidence is for caffeine in general, so it is indirect for these drinks.
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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 energy drink summary, re-checked nutrition against saved USDA FoodData Central data, read the FDA, NHS and WHO pages and re-read PubMed abstracts for 11 papers. 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. Funding is not stated in most abstracts; one risk-reports study has authors from the US FDA and a consumer group.
Sources 16
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Ajibo C, Van Griethuysen A, Visram S, Lake AA. Consumption of energy drinks by children and young people: a systematic review examining evidence of physical effects and consumer attitudes.. Public Health. 2024. PMID 38228408. DOI 10.1016/j.puhe.2023.08.024. (abstract)
- Clark I, Landolt HP. Coffee, caffeine, and sleep: A systematic review of epidemiological studies and randomized controlled trials.. Sleep Med Rev. 2017. PMID 26899133. DOI 10.1016/j.smrv.2016.01.006. (abstract)
- Committee on Nutrition and the Council on Sports Medicine and Fitness. Sports drinks and energy drinks for children and adolescents: are they appropriate?. Pediatrics. 2011. PMID 21624882. DOI 10.1542/peds.2011-0965. (abstract)
- Curran CP, Marczinski CA. Taurine, caffeine, and energy drinks: Reviewing the risks to the adolescent brain.. Birth Defects Res. 2017. PMID 29251842. DOI 10.1002/bdr2.1177. (abstract)
- Grgic J, Grgic I, Pickering C, Schoenfeld BJ, et al.. Wake up and smell the coffee: caffeine supplementation and exercise performance-an umbrella review of 21 published meta-analyses.. Br J Sports Med. 2020. PMID 30926628. DOI 10.1136/bjsports-2018-100278. (abstract)
- Gualberto PIB, Benvindo VV, Waclawovsky G, Deresz LF. Acute effects of energy drink consumption on cardiovascular parameters in healthy adults: a systematic review and meta-analysis of randomized clinical trials.. Nutr Rev. 2024. PMID 37695306. DOI 10.1093/nutrit/nuad112. (abstract)
- Mandato J, Kola R, Tyson T, Laffin L, et al.. The Effects of Energy Drinks on the Cardiovascular System: A Systematic Review.. Curr Cardiol Rep. 2025. PMID 41236610. DOI 10.1007/s11886-025-02293-w. (abstract)
- Markon AO, Jones OE, Punzalan CM, Lurie P, et al.. Caffeinated energy drinks: adverse event reports to the US Food and Drug Administration and the National Poison Data System, 2008 to 2015.. Public Health Nutr. 2019. PMID 31317857. DOI 10.1017/S1368980019001605. (abstract)
- Rubio C, Cámara M, Giner RM, González-Muñoz MJ, et al.. Caffeine, D-glucuronolactone and Taurine Content in Energy Drinks: Exposure and Risk Assessment.. Nutrients. 2022. PMID 36501132. DOI 10.3390/nu14235103. (abstract)
- Souza DB, Del Coso J, Casonatto J, Polito MD. Acute effects of caffeine-containing energy drinks on physical performance: a systematic review and meta-analysis.. Eur J Nutr. 2017. PMID 27757591. DOI 10.1007/s00394-016-1331-9. (abstract)
- Verster JC, Benson S, Johnson SJ, Scholey A, et al.. Mixing alcohol with energy drink (AMED) and total alcohol consumption: a systematic review and meta-analysis.. Hum Psychopharmacol. 2016. PMID 26781580. DOI 10.1002/hup.2513. (abstract)
- . US FDA: Spilling the Beans: How Much Caffeine Is Too Much?. . . (full-text)
- . NHS: Foods to avoid in pregnancy (caffeine section). . . (full-text)
- . USDA FoodData Central: fortified energy drink item (SR Legacy, FDC 171935). . . (full-text)
- . USDA FoodData Central: sugar-sweetened energy drink item (SR Legacy, FDC 173210). . . (full-text)
- . WHO: Healthy diet fact sheet. . . (full-text)
