Legumes · Legume
Tepary Beans
Phaseolus acutifolius · also called Tepary bean, Texas bean, haricot tepari (French)
Tepary beans are small seeds of a bean plant from the south-western United States and northern Mexico, eaten cooked in stews and soups. They give protein and fibre. We found no trial of tepary beans in people, so health claims are unproven. The key caution is that raw tepary beans must never be eaten: a plant reference records very high raw lectin activity, and raw flour killed mice and rats until the beans were soaked and cooked.
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 Tepary Beans
Tepary beans are small, drought-hardy seeds of a bean plant, eaten cooked. They are a source of protein and fibre. They are a food, not a proven remedy, and there is very little research on them. Never eat them raw or undercooked.
What it is
Tepary beans (Phaseolus acutifolius) are the seeds of a bean plant in the pea family, a different species from the common bean. PROTA calls it an ancient crop of the south-western United States and northern Mexico. The seeds come in white, yellow, brown, black and speckled types and are eaten dried and cooked in stews and soups, often with whole-grain maize.
USDA FoodData Central had no item for tepary beans when we first checked, and we could not re-check it today, so there are no USDA values here. A plant reference gives, per 100 g of dry seed: 353 kcal, 19.3 g protein, 1.2 g fat, 67.8 g carbohydrate, 4.8 g fibre, 112 mg calcium and 310 mg phosphorus. A 2021 lab paper measured flour on a dry basis and found 23.46% protein raw and 25.27% cooked. These are dry-weight numbers for uncooked beans, so they cannot be compared with cooked-bean tables, and the two sources disagree on fibre.
What the research shows
We found no trial of tepary beans in people. One 1990 test gave eight healthy volunteers portions of six traditional Pima foods, including white and yellow teparies; all had a low glycemic index (16 to 40), but the abstract does not give a separate tepary figure.
Pooled trials of pulses as a group (beans, chickpeas, lentils, peas) found LDL cholesterol about 0.17 mmol/L lower, lower fasting glucose markers and a very small weight loss of about 0.34 kg over roughly 6 weeks. These trials did not name tepary beans, so we cannot say the same holds for them. Harvard describes the evidence on legumes and diabetes prevention as mixed.
In the lab, cooked tepary flour was digested better than raw flour (about 62 to 64% against 48 to 50%). That is a laboratory test, not a result in people.
Food versus flour and extracts
The lab papers used flours, protein concentrates and, in 2025, an uncooked lectin-rich seed protein extract. That extract was toxic to small intestinal cells in the lab (IC50 10.08 and 108.91 micrograms per mL) and caused short-term DNA damage in mice at 1000 mg/kg, with no deaths in an acute mouse test. It is a safety signal for the raw extract, not a measure of what cooked beans do. The 2021 flour paper was funded by a Mexican university programme and the authors declared no conflicts.
Portions
The NHS counts 80 g of beans and pulses as one portion of 5 A DAY, and they count only once a day however much you eat. That is not specific to tepary beans, and this page gives no amounts to eat. Ask a doctor, pharmacist or dietitian what is right for you.
At a glance
Traditional uses history, not proof
- Eaten as dry beans after boiling, steaming, frying or baking, in stews and soups and with whole-grain maize
- A traditional food of the Pima people of the south-western United States
- Long use as food is not proof that it treats any condition
Studied for research
- Protein and fibre, low certainty (nutrient content from a plant reference and a lab paper)
- Blood sugar after meals, insufficient evidence (one 1990 test with no tepary-only result)
- Cholesterol, insufficient evidence for this bean (pulses as a group only)
- Body weight, insufficient evidence for this bean (pulses as a group only)
Main compounds
- Protein (low in sulphur amino acids)
- Dietary fibre
- Lectins (very high when raw)
- Gas-causing oligosaccharides
- Phytic acid and trypsin inhibitors
- Polyphenols
Common forms
- Dry beans, soaked and cooked until fully soft
- Flour made from cooked beans (lab figures only)
- Raw flour is not safe (animal deaths in a plant reference)
- Seed protein extracts are lab materials, not a food and not covered
Research links: 1990 meal test: traditional Pima foods · 2025 study: raw tepary seed protein extract · 2014 review: pulses and LDL cholesterol · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Phaseolus acutifolius
- Naming authority
- A.Gray (PROTA)
- Common names
- Tepary bean (English); Texas bean (English); Haricot tepari (French)
- Family or group
- Fabaceae (the legume or pea family), per PROTA. A different species from the common bean (Phaseolus vulgaris).
- Classification
- Plantae > Not verified > Not verified > Not verified > Fabaceae (Leguminosae-Papilionoideae), per PROTA > Phaseolus > Phaseolus acutifolius
- Native range
- PROTA: an ancient crop of the south-western United States and northern Mexico; wild types range from Arizona, New Mexico and Texas to Guatemala, with the core in north-western Mexico.
- Habitat
- PROTA: suited to arid regions, tolerant of drought, heat and a dry atmosphere.
- What it looks like
- Roots: Fibrous (PROTA).; Stems: Climbing, trailing or bushy annual herb, stems up to 4 m (PROTA).; Leaves: Three-leaflet leaves (PROTA).; Flowers: White, pink or pale lilac pea-type flowers (PROTA).; Fruit: A compressed pod 5 to 9 cm long with 2 to 9 seeds; seeds 4 to 7 mm, white, yellow, brown, purple, black or speckled (PROTA).
- Cultivation
- PROTA: mainly grown for mature dry seeds; grown in Mexico and Arizona, and in semi-arid parts of Africa; cultivation fell sharply after World War II and interest is now returning.
- Harvest and processing
- Dry seeds are eaten after boiling, steaming, frying or baking; in Uganda they are boiled and coarsely ground for soup (PROTA). Dry seeds harden in storage and take a long time to cook; white-seeded types cook faster than black-seeded types (PROTA).
- Look-alikes and adulterants
- Name: Common bean (Phaseolus vulgaris), pinto and lima beans; Note: Different bean species with their own pages and nutrient data.
- Sustainability and conservation
- PROTA says wild gene pools have shrunk through habitat loss and that the cultivated crop has suffered genetic erosion.
Photographs
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
Traditional use shows how it was used. It does not show that it works or is safe today.
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 |
|---|---|---|---|---|
| Protein | protein | Seed PROTA: 19.3 g per 100 g dry seed; 2021 lab paper: 23.46% in raw flour, 25.27% in cooked flour (dry basis) | Low in methionine and cysteine, like other pulses. Lab digestibility was higher in cooked than raw samples. 14 11 | Laboratory research |
| Dietary fibre | carbohydrate | Seed PROTA: 4.8 g per 100 g dry seed; lab flour: 2.96% raw, 2.44% cooked | Nutrient content only; no tepary-specific fibre trial was read. 14 11 | Reference |
| Lectins | protein | Seed Lectin activity 'exceptionally high' (PROTA); 2701.85 HU in a 2025 seed protein extract | Reduced by cooking. Raw flour was lethal to mice and rats in the PROTA record; an uncooked extract was toxic to intestinal cells in the lab. 14 5 | Animal research |
| Trypsin inhibitors, flatulent oligosaccharides and phytic acid | antinutritional factors | Seed Similar to cowpea and chickpea (PROTA); amounts not given | PROTA lists these as antinutritional factors; oligosaccharides are linked to flatulence. 14 | Reference |
| Polyphenols | polyphenols | Seed About 110 mg gallic acid equivalents per 100 g dry sample, quoted from another source by the 2021 paper | The 2021 paper says the polyphenol profile is not completely known. No health effect was read. 11 | Reference |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Slow starch digestion | Not specified | The 1990 authors say slow digestion and absorption of starch in traditional foods may have helped protect susceptible populations from diabetes; lab starch digestibility matched the glycemic index. This is a hypothesis. 1 | Laboratory research |
| Lectin binding to PPAR gamma (computer model) | PPAR gamma | The 2021 paper ran a computer docking model of tepary lectin to PPAR gamma. It is a computer prediction only, with no test in cells or people read. 11 | In silico |
| Cell and DNA damage by lectin-rich extract | Not specified | A raw lectin-rich extract was toxic to small intestinal cells in the lab and caused short-term DNA damage in mice at a high dose. An extract, not cooked beans. 5 | In vitro and animal |
Absorption, metabolism and elimination
- Absorption
- Not found for tepary beans.
- Distribution
- Not found.
- Metabolism
- Not found.
- Elimination
- Not found.
- Bioavailability
- A lab test found about 48 to 50% protein digestibility in raw flour and about 62 to 64% in cooked flour; not a human measure.
Isolated compounds versus whole extracts
The glycemic test used traditional foods and the pooled trials used whole pulses. The 2021 and 2025 papers used flours, protein concentrates and an uncooked seed protein extract; their results should not be read as what cooked whole beans do.
Nutritional composition
We found no USDA FoodData Central item for tepary beans in our earlier check, and the USDA service was rate-limited when we tried to re-check on 2026-10-26, so no USDA values are given. Dry tepary beans, per 100 g (PROTA, figures originally from Leung, Busson and Jardin 1968): 353 kcal, water 8.6 g, protein 19.3 g, fat 1.2 g, carbohydrate 67.8 g, fibre 4.8 g, calcium 112 mg, phosphorus 310 mg, thiamin 0.33 mg, riboflavin 0.12 mg, niacin 2.8 mg, vitamin C 0. A 2021 lab paper measured flour on a dry basis: protein 23.46% raw and 25.27% cooked, dietary fibre 2.96% and 2.44%. These are dry-weight figures for uncooked beans or flour, so they are not comparable with cooked-bean tables on other pages; 100 g dry beans is also much more than a usual serving once they take up water in cooking. The two sources disagree on protein and fibre, which fits natural variation between varieties and methods. Cooked-bean values were not found, and we did not convert or invent any.
1 low certainty3 not enough evidence
What was looked at
The 4 benefits and uses checked for Tepary Beans, each with how strong the evidence is. Tap one to open it.
- Protein and fibre (nutrient content)Low certainty
- Blood sugar after meals (glycemic response)Not enough evidence
- Cholesterol (pulses as a group)Not enough evidence
- Body weight (pulses as a group)Not enough evidence
Lab markers tracked in the studies
Glycemic index (after-meal blood glucose)Fasting blood glucose (pulses as a group)Protein digestibility (laboratory test)LDL cholesterol (pulses as a group)Body weight (pulses as a group)
What is Tepary Beans good for?
The few studied uses and how strong the evidence is for each. No study of tepary beans in people on any health outcome was found; most results are for pulses as a group.
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.
Protein and fibre (nutrient content)
Low certaintyDry tepary beans have about 19.3 g of protein and 4.8 g of fibre per 100 g by one plant reference, and a 2021 lab paper found 23 to 25 percent protein in tepary flour. These are nutrient facts about the dry bean, not trials in people. Raw bean protein was digested less well in the lab than cooked.
2 studiesDry beans and flour from raw or cooked beans (lab figures). Not advic…
Studies, doses and limits
What the trials found
No human study of tepary protein or fibre was read. PROTA gives dry-seed values per 100 g: 353 kcal, protein 19.3 g, fat 1.2 g, carbohydrate 67.8 g, fibre 4.8 g. A 2021 laboratory paper measured flour: protein 23.46% raw and 25.27% cooked (dry basis), dietary fibre 2.96% and 2.44%. Lab protein digestibility was about 48 to 50% in raw flour and about 62 to 64% in cooked flour.
Results
Tepary beans contain protein and fibre like other dry beans. Cooked flour scored better than raw on lab digestibility. The two sources disagree on fibre (4.8 g in PROTA, under 3% in the lab flour), which fits natural variation and different methods.
Effect sizes as reported
PROTA: protein 19.3 g and fibre 4.8 g per 100 g dry seed. Lab flour: protein 23.46% (raw) and 25.27% (cooked); in vitro digestibility 48.20 to 49.80% (raw) versus 61.77 to 63.61% (cooked).
Why this rating
Nutrient content is measurable, but it comes from one plant reference and one laboratory paper, in dry weight, with no human data on tepary beans.
Form and dose studied
Dry beans and flour from raw or cooked beans (lab figures). Not advice.
Limits
Dry-weight values are not comparable with cooked-bean tables. USDA values for tepary beans were not found. Lab digestibility is not a trial in people.
Why researchers looked
Tepary beans are a drought-hardy bean, so researchers ask how good a food protein source they are.
Traditional use
Tepary beans are an old crop of the south-western United States and northern Mexico, eaten cooked in stews, soups and with whole-grain maize. Long use as food is not proof that it treats any condition.
Proposed mechanism Laboratory research
Like other pulses, the protein is low in the sulphur amino acids methionine and cysteine (PROTA, 2021 lab paper). Cooking raised lab digestibility.
A proposed mechanism does not show that the effect happens in people.
Raw tepary beans are not safe to eat; see the Safety tab.
Blood sugar after meals (glycemic response)
Not enough evidenceIn a 1990 test, eight healthy volunteers ate portions of six traditional Pima foods, including white and yellow teparies. All the foods had a low glycemic index (16 to 40, glucose = 100). The abstract does not say what the tepary beans scored on their own. Pooled trials of pulses in general found lower fasting blood sugar markers.
3 studiesCooked traditional foods; pulses as food in the pooled trials.
Studies, doses and limits
What the trials found
Brand 1990: equal 25 g carbohydrate portions of six foods were fed to eight healthy volunteers; calculated glycemic indices ranged from 16 +/- 2 (acorns) to 40 +/- 5 (corn). A 2009 meta-analysis of 41 trials of pulses (chickpeas, beans, peas, lentils) found lower fasting glucose (-0.82) and insulin (-0.49) with pulses alone, but with high unexplained differences between trials. Harvard says research on legumes and diabetes prevention is mixed.
Results
Teparies were part of a low-glycemic-index group of foods, but no separate tepary number was given and healthy people, not people with diabetes, were tested. The pooled pulse results are not specific to tepary beans.
Effect sizes as reported
Glycemic index 16 to 40 for the six foods (no tepary-only value). Pulses alone: fasting glucose SMD -0.82 (95% CI -1.36 to -0.27).
Why this rating
One tiny 1990 meal test with no tepary-only result, plus pooled trials that did not name tepary beans.
Form and dose studied
Cooked traditional foods; pulses as food in the pooled trials.
Who was studied
Eight healthy volunteers; adults with and without diabetes in the pooled trials.
Limits
No tepary-specific figure; healthy people only; single meals; 1990. Pooled trials mix many pulses.
Why researchers looked
Researchers asked whether slowly digested traditional foods helped protect the Pima from diabetes.
Traditional use
White and yellow teparies were among the traditional foods of the Pima people. Long use as food is not proof that it treats any condition.
Proposed mechanism Laboratory research
The authors point to slow digestion and absorption of the starch (lab starch digestibility matched the glycemic index).
A proposed mechanism does not show that the effect happens in people.
If you take medicine for diabetes, ask your clinician before big diet changes.
Cholesterol (pulses as a group)
Not enough evidencePooled trials of diets with pulses such as beans, chickpeas and lentils found LDL cholesterol about 0.17 mmol/L lower. These trials did not test tepary beans specifically, so nothing is known about tepary beans and cholesterol.
1 studiesPulses as food (trial detail: median 130 g a day, not advice).
Studies, doses and limits
What the trials found
A 2014 meta-analysis of 26 randomised trials (1,037 adults, at least 3 weeks) found that diets emphasising pulses (median 130 g a day, about one serving) lowered LDL cholesterol by 0.17 mmol/L (95% CI 0.09 to 0.25) compared with similar diets without pulses. Apolipoprotein B and non-HDL cholesterol did not change. The abstract does not list tepary beans.
Results
A small average fall in LDL for pulses as a group. Nothing tepary-specific was found.
Effect sizes as reported
LDL mean difference -0.17 mmol/L (95% CI -0.25 to -0.09).
Why this rating
Reasonable evidence for pulses as a group (low-to-moderate), but no study of tepary beans, so for this bean it is insufficient.
Form and dose studied
Pulses as food (trial detail: median 130 g a day, not advice).
Who was studied
Adults in trials.
Limits
Pulses as a group; tepary beans not named; authors call for longer and better trials.
Why researchers looked
Beans are high in fibre, so people ask whether eating them lowers cholesterol.
Traditional use
Tepary beans are eaten cooked in stews and soups. 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.
Body weight (pulses as a group)
Not enough evidencePooled trials found people eating diets with pulses lost slightly more weight than people not eating them, about 0.34 kg over roughly 6 weeks. This was pulses as a group, not tepary beans.
1 studiesPulses as food (trial detail: median 132 g a day, not advice).
Studies, doses and limits
What the trials found
A 2016 meta-analysis of 21 randomised trials (940 adults, median 6 weeks) found diets with about one serving a day (median 132 g) of pulses gave a weight change of -0.34 kg (95% CI -0.63 to -0.04, P = 0.03) compared with diets without pulses. Six trials suggested lower body fat percentage.
Results
A very small average change in short trials of pulses. Nothing tepary-specific was found.
Effect sizes as reported
Weight -0.34 kg (95% CI -0.63 to -0.04), median 6 weeks.
Why this rating
A very small, short-term effect for pulses as a group (low certainty), and no study of tepary beans.
Form and dose studied
Pulses as food (trial detail: median 132 g a day, not advice).
Who was studied
Adults in trials.
Limits
Short trials; pulses as a group; the average change is tiny.
Why researchers looked
Beans are filling foods rich in fibre and protein, so researchers ask whether they help with weight control.
Traditional use
Tepary beans are eaten cooked in stews and soups. 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.
Connections to the rest of health
How Tepary Beans 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 |
|---|---|---|---|---|
| Healthy Weight | Low certainty | Protein and fibre (nutrient content): Dry tepary beans have about 19.3 g of protein and 4.8 g of fibre per 100 g by one plant reference, and a 2021 lab paper found 23 to 25 percent protein in tepary flour. These are nutrient facts about the dry bean, not trials in people. Raw bean protein was digested less well in the lab than cooked. | 14 11 | |
| Healthy Weight | Not enough evidence | Blood sugar after meals (glycemic response): In a 1990 test, eight healthy volunteers ate portions of six traditional Pima foods, including white and yellow teparies. All the foods had a low glycemic index (16 to 40, glucose = 100). The abstract does not say what the tepary beans scored on their own. Pooled trials of pulses in general found lower fasting blood sugar markers. Body weight (pulses as a group): Pooled trials found people eating diets with pulses lost slightly more weight than people not eating them, about 0.34 kg over roughly 6 weeks. This was pulses as a group, not tepary beans. | 1 4 9 3 | |
| Healthy Aging | Not enough evidence | Cholesterol (pulses as a group): Pooled trials of diets with pulses such as beans, chickpeas and lentils found LDL cholesterol about 0.17 mmol/L lower. These trials did not test tepary beans specifically, so nothing is known about tepary beans and cholesterol. | 2 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Digestive System | Biological association | Low certainty | Studied for: Protein and fibre (nutrient content) | 14 11 |
| Endocrine System | Biological association | Not enough evidence | Studied for: Blood sugar after meals (glycemic response) | 1 4 9 |
| Cardiovascular System | Biological association | Not enough evidence | Studied for: Cholesterol (pulses as a group) | 2 |
| Metabolism Weight | Biological association | Not enough evidence | Studied for: Body weight (pulses as a group) | 3 |
C. Body parts and organs
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Food poisoning | Adverse effect or risk | Documented risk | PROTA reports high raw lectin activity and deaths in mice and rats fed raw flour, removed by soaking and cooking. No human poisoning report was read. PROTA records high raw lectin activity and deaths in mice and rats fed raw flour, removed by soaking and cooking. No human poisoning report was read. Preparation or compound: Raw or undercooked tepary beans |
14 7 |
| Irritable bowel syndrome | Documented risk | A hospital low-FODMAP leaflet names beans and pulses as the main source of galacto-oligosaccharides and asks to limit them for four to six weeks. A hospital low-FODMAP leaflet names beans and pulses as the main source of galacto-oligosaccharides. Preparation or compound: Beans and pulses (GOS) |
6 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Glycemic index (after-meal blood glucose) | Biological association | Not enough evidence | Measured in trials: low values. A lab change is not the same as a health benefit. | 1 |
| Fasting blood glucose (pulses as a group) | Biological association | Low certainty | Measured in trials: lowered. A lab change is not the same as a health benefit. | 4 |
| Protein digestibility (laboratory test) | Biological association | Very low certainty | Measured in trials: higher in cooked flour. A lab change is not the same as a health benefit. | 11 |
| LDL cholesterol (pulses as a group) | Biological association | Low certainty | Measured in trials: lowered. A lab change is not the same as a health benefit. | 2 |
| Body weight (pulses as a group) | Biological association | Low certainty | Measured in trials: lowered. A lab change is not the same as a health benefit. | 3 |
K. Biological pathways
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Protein | Biological association | In vitro | Low in methionine and cysteine, like other pulses. Lab digestibility was higher in cooked than raw samples. Preparation or compound: Seed |
14 11 |
| Dietary fibre | Biological association | Reference | Nutrient content only; no tepary-specific fibre trial was read. Preparation or compound: Seed |
14 11 |
| Lectins | Biological association | Animal | Reduced by cooking. Raw flour was lethal to mice and rats in the PROTA record; an uncooked extract was toxic to intestinal cells in the lab. Preparation or compound: Seed |
14 5 |
| Trypsin inhibitors, flatulent oligosaccharides and phytic acid | Biological association | Reference | PROTA lists these as antinutritional factors; oligosaccharides are linked to flatulence. Preparation or compound: Seed |
14 |
| Polyphenols | Biological association | Reference | The 2021 paper says the polyphenol profile is not completely known. No health effect was read. Preparation or compound: Seed |
11 |
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 3 lab markers
Tap a number to show only those markers. Counts are markers, not people.
The evidence
The research centre for Tepary Beans. 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 tepary beans summary, re-read the PROTA plant reference, the 2021 laboratory paper, the FDA, Harvard, NHS, MedlinePlus and hospital leaflet pages, and re-read PubMed abstracts for the five studies listed. Only abstracts were read for studies. Health Canada could not be re-opened today. Items we could not verify are flagged in the research gaps.
Study library: every study we checked 14
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Brand 1990 Plasma glucose and insulin responses to traditional Pima Indian meals. Am J Clin Nutr · PMID 2178389 · DOI |
Small meal test |
8 Eight healthy volunteers (Caucasian) |
Six traditional Pima staple foods: corn, lima beans, white and yellow teparies, mesquite, acorns Cooked food (preparation not given in the abstract) Portions with 25 g of carbohydrate Single meal tests · vs Glucose as the standard (glycemic index scale) |
All calculated glycemic indices were low, from 16 (acorns) to 40 (corn). Insulin responses and lab starch digestibility matched the glycemic index. The abstract does not give a separate figure for tepary beans. Glycemic index range 16 +/- 2 to 40 +/- 5 across the six foods (Not applicable (means +/- SEM)) Methods, limits and fundingOutcomes: Blood glucose and insulin after the meal; in vitro starch digestibility Limitations: Eight healthy people, single meals. No separate tepary figure in the abstract. People with diabetes were not tested. 1990 study. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| Ha 2014 Effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction: a systematic review and meta-analysis of randomized controlled trials. CMAJ · PMID 24710915 · DOI |
Systematic review meta analysis |
1037 1,037 adults in 26 randomised trials |
Diets emphasising pulses (beans, chickpeas, lentils and peas) Pulses as food Median 130 g/day (about 1 serving) At least 3 weeks · vs Isocaloric diets without pulses |
Pulse diets lowered LDL cholesterol. No effect on apolipoprotein B or non-HDL cholesterol was seen. LDL mean difference -0.17 mmol/L (95% CI -0.25 to -0.09 mmol/L) Methods, limits and fundingOutcomes: LDL cholesterol, apolipoprotein B, non-HDL cholesterol Limitations: Pulses as a group; the abstract does not list tepary beans. Authors call for longer, better trials. Funding and conflicts: Funding is not stated in the abstract. Registration: NCT01594567 Read: abstract |
| Kim 2016 Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr · PMID 27030531 · DOI |
Systematic review meta analysis |
940 940 adults in 21 randomised trials |
Diets with whole pulses (beans, lentils, chickpeas, dry peas) Pulses as food Median 132 g/day (about 1 serving) Median 6 weeks (at least 3) · vs Diets without pulses |
Weight was 0.34 kg lower with pulse diets, in both weight-loss and weight-maintaining diets, with low heterogeneity. Six trials suggested lower body fat percentage. Body weight -0.34 kg (95% CI -0.63 to -0.04 kg; P = 0.03) Methods, limits and fundingOutcomes: Body weight, waist circumference, body fat Limitations: Very small, short-term effect; pulses as a group; tepary beans not named in the abstract. Funding and conflicts: Funding is not stated in the abstract. Registration: NCT01594567 Read: abstract |
| Sievenpiper 2009 Effect of non-oil-seed pulses on glycaemic control: a systematic review and meta-analysis of randomised controlled experimental trials in people with and without diabetes. Diabetologia · PMID 19526214 · DOI |
Systematic review meta analysis |
41 randomised trials in people with and without diabetes | Non-oil-seed pulses (chickpeas, beans, peas, lentils and others), alone or in low-GI or high-fibre diets Pulses as food Not given in the abstract At least 7 days · vs Control diets |
Pulses alone (11 trials) lowered fasting glucose and insulin. Pulses in low-GI diets (19 trials) lowered HbA1c or fructosamine. Pulses in high-fibre diets (11 trials) lowered fasting glucose and glycosylated proteins. Differences between trials were high and unexplained for most outcomes. Standardised mean differences: fasting glucose -0.82 (pulses alone); insulin -0.49; glycosylated proteins -0.28 (low-GI diets) (Fasting glucose -0.82 (-1.36 to -0.27); insulin -0.49 (-0.93 to -0.04); glycosylated proteins -0.28 (-0.42 to -0.14)) Methods, limits and fundingOutcomes: Fasting glucose, insulin, glycosylated proteins (HbA1c or fructosamine) Limitations: Pulses as a group; tepary beans not named in the abstract. High unexplained heterogeneity. 2009. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| Valadez-Vega 2025 Assessment of Genotoxicity and Cytotoxicity of Tepary Bean (Phaseolus acutifolius) Seed Protein Extract. Life (Basel) · PMID 41465875 · DOI |
Lab animal study mouse and cells |
Mice and small intestinal epithelial cells in the lab | Lectin-rich protein extract of tepary bean seeds (lectin activity 2701.85 HU) Seed protein extract (not cooked beans) Acute test and up to 1000 mg/kg in mice (see ci) Up to 48 h and longer in mice · vs Untreated controls |
The extract caused no deaths in the acute mouse test. It was toxic to small intestinal cells in the lab (IC50 10.08 and 108.91 micrograms per mL in two assays). In mice, 11 micronucleated erythrocytes (DNA damage) were seen at 48 h at 1000 mg/kg, but no genotoxicity with longer treatment times. Cytotoxic IC50 10.08 and 108.91 micrograms/mL; genotoxic damage at 48 h, 1000 mg/kg (Not given in the abstract) Methods, limits and fundingOutcomes: Death in mice; cell toxicity; DNA damage (micronucleated red cells) Limitations: Lab and mouse study of an uncooked extract; cannot be read as what cooked beans do to people. Funding and conflicts: Funding is not stated in the abstract. Read: abstract |
| s-cuh-fodmap Cambridge University Hospitals NHS Foundation Trust: Low FODMAP diet leaflet · Source |
Patient leaflet n/a |
Methods, limits and fundingRead: full-text | ||
| s-fda-natural-toxins FDA: Natural Toxins in Food · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-harvard-lectins Harvard T.H. Chan School of Public Health: Lectins (The Nutrition Source) · Source |
Expert site n/a |
Methods, limits and fundingRead: full-text | ||
| s-harvard-legumes Harvard T.H. Chan School of Public Health: Legumes and Pulses (The Nutrition Source) · Source |
Expert site n/a |
Methods, limits and fundingRead: full-text | ||
| s-healthcanada-lectins Health Canada: Lectins in legumes · Source |
Health agency n/a |
Methods, limits and fundingRead: summary-only | ||
| s-lopezibarra-2021 Lopez-Ibarra C et al. Protein concentrates on tepary bean (Phaseolus acutifolius Gray) as a functional ingredient: in silico docking of tepary bean lectin to PPAR gamma. Front Nutr 2021 · Source |
Laboratory paper n/a |
Methods, limits and fundingRead: full-text | ||
| s-medlineplus-foodallergy MedlinePlus: Food allergy · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-nhs-5aday NHS: 5 A DAY, what counts? · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-prota PROTA (Plant Resources of Tropical Africa) via Pl@ntUse: Phaseolus acutifolius · Source |
Plant reference n/a |
Methods, limits and fundingRead: full-text |
What we do not know yet
- No trial of tepary beans in people was found for any outcome; the cholesterol, blood sugar and weight results are for pulses as a group.
- The 1990 meal test gave no tepary-only glycemic index in its abstract.
- No source was read on tepary bean allergy, kidney disease, pregnancy, breastfeeding, children, choking risk, medicine interactions, contaminants or a tepary-specific cooking time.
- USDA values for tepary beans were not found; cooked-bean nutrition was not found.
- The Health Canada page could not be re-opened on 2026-10-26.
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 3
Fasting blood glucose (pulses as a group)
Lowered in trials
Blood sugar measured after not eating overnight.
Low certaintyResults and what it means
Why it was measured
A basic measure of blood sugar control.
Statistical vs. clinical meaning
Pooled pulses lowered fasting glucose, but tepary beans were not named.
Safety implication
Ask a clinician before diet changes if you take diabetes medicine.
| Study | Result | People | Product |
|---|---|---|---|
| 4 | Pulses alone: fasting glucose SMD -0.82 (95% CI -1.36 to -0.27); insulin -0.49 (-0.93 to -0.04); high unexplained differences between trials | 41 trials in people with and without diabetes | Pulses as food, at least 7 days |
LDL cholesterol (pulses as a group)
Lowered in trials
The 'bad' cholesterol carried in the blood. Higher levels are linked to more heart disease.
Low certaintyResults and what it means
Why it was measured
It is the usual blood marker used in diet trials for heart risk.
Statistical vs. clinical meaning
A small average fall in short trials of pulses; tepary beans were not named.
Safety implication
None specific.
| Study | Result | People | Product |
|---|---|---|---|
| 2 | LDL mean difference -0.17 mmol/L (95% CI -0.25 to -0.09); no effect on apolipoprotein B or non-HDL | 1,037 adults in 26 trials | Diets emphasising pulses, median 130 g/day, at least 3 weeks |
Body weight (pulses as a group)
Lowered in trials
Weight in kilograms measured in a trial.
Low certaintyResults and what it means
Why it was measured
A basic measure used in diet trials.
Statistical vs. clinical meaning
A very small average change; pulses as a group.
Safety implication
None specific.
| Study | Result | People | Product |
|---|---|---|---|
| 3 | Body weight -0.34 kg (95% CI -0.63 to -0.04), P = 0.03, median 6 weeks | 940 adults in 21 trials | Diets with whole pulses, median 132 g/day |
Other 2
Glycemic index (after-meal blood glucose)
Low values in trials
A score for how much a food raises blood sugar compared with pure glucose (glucose = 100).
Not enough evidenceResults and what it means
Why it was measured
It shows how fast the starch in a food is digested and absorbed.
Statistical vs. clinical meaning
Teparies belonged to a low-GI group of foods, but their own value is not reported in the abstract.
Safety implication
None specific.
| Study | Result | People | Product |
|---|---|---|---|
| 1 | All six traditional foods had a low glycemic index, from 16 (acorns) to 40 (corn); no separate tepary figure in the abstract | 8 healthy volunteers | 25 g carbohydrate portions of corn, lima beans, white and yellow teparies, mesquite and acorns |
Protein digestibility (laboratory test)
Higher in cooked flour in trials
How much of a food's protein is broken down in a lab model of digestion.
Very low certaintyResults and what it means
Why it was measured
It estimates how well the body could use the protein.
Statistical vs. clinical meaning
Lab only; it suggests cooking improves protein digestibility.
Safety implication
None specific.
| Study | Result | People | Product |
|---|---|---|---|
| 11 | About 48.20 to 49.80% in raw samples versus 61.77 to 63.61% in cooked samples | Laboratory samples (no people) | Flour and protein concentrate from raw and cooked tepary beans |
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 3
- Never eat tepary beans raw or undercooked. The PROTA plant reference says tepary lectin activity is 'exceptionally high' but readily reduced by cooking. It records that raw tepary bean flour caused death in mice and rats within 3 to 4 days, and that soaking and cooking the seeds eliminated the toxicity completely. That is animal evidence; no human poisoning report for tepary beans was read. For beans in general, the FDA says the lectin PHA in raw or undercooked beans can cause nausea, severe vomiting and diarrhea. Animal research 14 7
- No tepary-specific cooking time was found. PROTA says dry tepary seeds harden in storage and take a long time to cook. The FDA's published steps for beans (soak at least 5 hours, boil in fresh water at least 30 minutes) are the longest figures read; they are not written for tepary beans. Harvard says raw beans simmered at low heat, such as in a slow cooker, will not lose all their lectins. Follow your national food-safety authority and cook until fully soft. Authoritative guidance 14 7 8 10
- Raw flour or ground raw beans. The animal deaths in the PROTA record were from raw tepary flour. Cook the beans before grinding them for food. Animal research 14
Side effects 3
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Nausea, severe vomiting and diarrhea from raw or undercooked beans (lectin PHA, described for beans in general) Written about beans in general (kidney beans named). No human case of tepary bean poisoning was read. | Not given for tepary beans. | can be severe Not stated for tepary beans. | Authoritative guidance 7 8 |
| Gas, bloating and stomach cramps PROTA lists gas-causing oligosaccharides in tepary seeds and flatulence among the reasons people are reluctant to use it. Harvard describes gas from fermentable carbohydrates in legumes generally. | Not measured for tepary beans. | mild Not studied | Authoritative guidance 14 9 |
| Intestinal cell toxicity and short-term DNA damage from a raw lectin-rich seed extract (lab and mice) An uncooked protein extract, not cooked beans. A safety signal, not proof of harm from eating cooked beans. | IC50 10.08 and 108.91 micrograms/mL in two cell assays; 11 micronucleated red cells at 48 h at 1000 mg/kg in mice; no deaths in the acute mouse test; no genotoxicity with longer treatment times. | unknown for people Not studied | In vitro and animal 5 |
Liver
No liver injury from eating tepary beans was found in the sources read. A liver-safety source (such as LiverTox) was not searched for food.
How often. No frequency was found.
Monitoring. No agency monitoring advice was found.
This is a safety connection. It is not evidence that Tepary Beans supports liver health.
Medicines and supplements 2
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Medicines for diabetes prescription | Pooled pulse trials lowered blood sugar markers a little, and beans were low-glycemic-index foods; a big diet change could in theory add to a medicine's effect. | No source read ties tepary beans to a specific medicine interaction. This is a general caution, not a documented interaction. | Theoretical Not enough evidence 4 1 | Ask your clinician or pharmacist before making big diet changes if you take diabetes medicine. |
| Any other medicine general | No source read names any medicine interaction with tepary beans, and no vitamin K or potassium value for tepary beans was found. | None found Not enough evidence | Ask your pharmacist if you take warfarin or other medicine and plan to change your diet a lot. |
Who should check first 3
| Situation | Advice | Evidence |
|---|---|---|
| Raw or undercooked tepary beans, or raw bean flour | Do not eat. Soak, drain and cook thoroughly until fully soft. | Animal research 14 7 |
| Known allergy to beans, peanuts or other legumes | Ask an allergist before trying tepary beans. No source on tepary bean allergy or cross-reaction was read. For trouble breathing or swelling of the face or throat after any food, call 911 or your local emergency number. | Authoritative guidance 12 |
| People on a low-FODMAP plan (for example for irritable bowel symptoms) | A hospital leaflet names beans and pulses as the main source of galacto-oligosaccharides and asks people to limit them for an initial four to six weeks, with a dietitian. Tepary beans are not named in the leaflet. Ask your dietitian. | Authoritative guidance 6 |
Overdose, product quality and regulators
Summary. Raw tepary beans are toxic to animals in the one source read (PROTA); cooking removes that toxicity. No toxicity of properly cooked tepary beans as food was found.
Animal. Raw tepary flour caused death in mice and rats within 3 to 4 days; soaking and cooking removed it (PROTA). A lectin-rich extract caused no deaths in an acute mouse test but was toxic to intestinal cells and caused short-term DNA damage in mice at 1000 mg/kg (2025).
Human doses studied. No human dosing or poisoning study of tepary beans was found.
Overdose response. Not found.
Genotoxicity. A 2025 extract study found micronucleated red cells at 48 h at 1000 mg/kg in mice, not with longer treatment; extract only.
Toxic or hazardous parts. Raw or undercooked seeds (lectins, PROTA).
Nothing on mould, mycotoxins, pesticide residues or heavy metals in tepary beans was read.
Cooking dry beans. Harvard says cooking (boiling or stewing) or soaking for several hours can inactivate most lectins, and that undercooking or slow-cooker simmering of raw beans will not remove them all. The FDA gives 5 hours of soaking and at least 30 minutes of boiling in fresh water for beans in general. 8 7
| Body | Action | Date |
|---|---|---|
| FDA (United States) | Natural Toxins in Food: PHA lectin in raw or undercooked beans can cause nausea, severe vomiting and diarrhea; soak beans at least 5 hours and boil in fresh water at least 30 minutes source | 2024-09-26 |
When to get medical help
- Trouble breathing, swelling of the lips, face or throat, widespread hives, repeated vomiting or collapse after eating beans (possible anaphylaxis): call 911 or your local emergency number
- Severe vomiting or diarrhea after eating raw or undercooked beans: seek medical advice
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
Are tepary beans safe to eat?
Yes when soaked and thoroughly cooked. PROTA says raw tepary flour killed mice and rats but soaking and cooking removed the toxicity. Never eat them raw. No human poisoning report was read.
What are tepary beans good for?
How long do I boil tepary beans?
Why must tepary beans not be eaten raw?
Can I cook tepary beans in a slow cooker?
Are tepary beans good for blood sugar or diabetes?
Do tepary beans lower cholesterol?
Not studied for tepary beans. Pooled trials of pulses as a group found LDL cholesterol about 0.17 mmol/L lower.
Do tepary beans cause gas?
Are tepary beans low FODMAP?
No tepary-specific rating was found. A hospital low-FODMAP leaflet names beans and pulses as the main source of galacto-oligosaccharides and asks to limit them for an initial four to six weeks. Ask a dietitian.
Can you be allergic to tepary beans?
We read no source on tepary bean allergy. Any food can cause an allergic reaction. Ask an allergist if you have a legume allergy. For trouble breathing or swelling of the face or throat, call 911 or your local emergency number.
Why are there no USDA numbers for tepary beans?
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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 tepary beans summary, re-read the PROTA plant reference, the 2021 laboratory paper, the FDA, Harvard, NHS, MedlinePlus and hospital leaflet pages, and re-read PubMed abstracts for the five studies listed. Only abstracts were read for studies. Health Canada could not be re-opened today. 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 14
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Brand JC, Snow BJ, Nabhan GP, Truswell AS. Plasma glucose and insulin responses to traditional Pima Indian meals.. Am J Clin Nutr. 1990. PMID 2178389. DOI 10.1093/ajcn/51.3.416. (abstract)
- Ha V, Sievenpiper JL, de Souza RJ, et al.. Effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction: a systematic review and meta-analysis of randomized controlled trials.. CMAJ. 2014. PMID 24710915. DOI 10.1503/cmaj.131727. (abstract)
- Kim SJ, de Souza RJ, Choo VL, et al.. Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials.. Am J Clin Nutr. 2016. PMID 27030531. DOI 10.3945/ajcn.115.124677. (abstract)
- Sievenpiper JL, Kendall CW, Esfahani A, et al.. Effect of non-oil-seed pulses on glycaemic control: a systematic review and meta-analysis of randomised controlled experimental trials in people with and without diabetes.. Diabetologia. 2009. PMID 19526214. DOI 10.1007/s00125-009-1395-7. (abstract)
- Valadez-Vega C, Ortigoza-Fonseca L, Betanzos-Cabrera G, et al.. Assessment of Genotoxicity and Cytotoxicity of Tepary Bean (Phaseolus acutifolius) Seed Protein Extract.. Life (Basel). 2025. PMID 41465875. DOI 10.3390/life15121937. (abstract)
- . Cambridge University Hospitals NHS Foundation Trust: Low FODMAP diet leaflet. . . (full-text)
- . FDA: Natural Toxins in Food. . . (full-text)
- . Harvard T.H. Chan School of Public Health: Lectins (The Nutrition Source). . . (full-text)
- . Harvard T.H. Chan School of Public Health: Legumes and Pulses (The Nutrition Source). . . (full-text)
- . Health Canada: Lectins in legumes. . . (summary-only)
- . Lopez-Ibarra C et al. Protein concentrates on tepary bean (Phaseolus acutifolius Gray) as a functional ingredient: in silico docking of tepary bean lectin to PPAR gamma. Front Nutr 2021. . . (full-text)
- . MedlinePlus: Food allergy. . . (full-text)
- . NHS: 5 A DAY, what counts?. . . (full-text)
- . PROTA (Plant Resources of Tropical Africa) via Pl@ntUse: Phaseolus acutifolius. . . (full-text)
Where to buy
Check the label first. Whatever you buy, look for these:
- A recent packed-on date: very old dried beans cook unevenly
- Organic or not, and the country of origin
- Whether you want dried or canned
- Soak and cook thoroughly; some raw beans are unsafe
Talk to a pharmacist or doctor before you start any supplement, especially if you take medicines. See the Safety tab for interactions.
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