Beans and lentils
Phaseolus vulgaris / Lens culinaris
Seeds & Grains. Latin American & Amazon, Middle Eastern & Unani and Modern nutrition.
Also called Common bean, Kidney beans, Lentils, Frijoles, Dal
Spanish: Frijoles y lentejas
Sanskrit: मसूर (Masur)
Raw kidney beans are toxicBeans and lentils are the dried seeds of pod plants. They are inexpensive foods and good sources of protein, fiber and folate.
Did you know? Lentils were among the first crops farmed in the Fertile Crescent, more than 8,000 years ago.
What it may help, and how strong the proof is
- Cholesterol. Meta-analyses of randomized trials find that diets with pulses lower LDL cholesterol modestly, by roughly 7 mg/dL in one review, though results vary between trials.See the research: 89 studies in peopleGood proof
- Blood sugar. Pulse-rich diets lowered fasting blood sugar and insulin in several trials, but results differ widely between studies.See the research: 115 studies in peoplePromising proof
- Digestion & gut health. Beans and lentils are high in fiber, which supports regular bowel movements. Gas and bloating are common when people first eat more of them.See the research: 85 studies in peoplePromising proof
- Weight. Pulses are filling and low in fat, so they can help people eat less overall. Beans alone have not been shown to cause weight loss.See the research: 126 studies in peoplePromising proof
Parts of the body
Heart & vessels, Liver, Pancreas & blood sugar, Gut & intestines, Stomach, Energy & metabolism
Traditional use
Beans are a staple across Latin America, from Mexican frijoles to Andean stews. Lentils are a daily food in Middle Eastern and South Asian cooking, in soups and as dal, and people have valued them for their protein and fiber for a very long time.
How it is classified
How people take it
A typical serving is about half a cup of cooked beans or lentils, and many trials used about one serving a day. Soak dried beans before cooking, then boil them well. Red lentils cook quickly and work well in soups and dal.
Food and powder.
Where to get it
Common beans grow across the Americas and Africa, and lentils are major crops in Canada, India and the Middle East. Dried beans and lentils are sold in bags, canned and ready to eat, and as flour.
Be careful
Raw or undercooked kidney beans contain a lectin that causes severe nausea and vomiting. Soak them for at least 5 hours, drain the water, and boil them hard for at least 10 minutes. Many food-safety guides suggest 30 minutes to be safer. Slow cookers often do not get hot enough to destroy the toxin. Fava beans, a different bean, can cause a serious reaction in people with G6PD deficiency. Beans and lentils can cause bloating and gas, and people with a legume allergy, including some with peanut allergy, should check with a doctor first. Food amounts are generally fine in pregnancy, and lentils are a good folate source. Beans and lentils are rich in potassium and phosphorus, so people with advanced kidney disease should ask their care team how much to eat.
Avoid if: legume allergy; fava beans with G6PD deficiency.
Mixing with other things
- Works well together
Barley and lentil soup is a classic pairing across the Middle East.
- Works well together
Cumin is a common spice in lentil and bean dishes, from Indian dal to Middle Eastern stews.
- Worth knowingDiabetes medicine (metformin, insulin, glipizide, Ozempic)
Pulses can lower blood sugar slightly, so people on diabetes medicines should watch their readings when they eat more of them.
The honest take
Beans and lentils are inexpensive, filling foods, and their LDL and blood sugar benefits are real but modest. Results differ widely between trials. Dried kidney beans need proper soaking and boiling to be safe, and a slow cooker is not enough.
Sources
Each “See the research” link opens PubMed, the U.S. National Library of Medicine's index of medical studies, showing only trials and reviews done in people. The number tells you how much a use has been tested, not whether it worked. The proof rating tells you that.
Study counts checked October 2026.