Beans

Legumes

What's inside beans, and where does it go in your body?

Black, kidney, pinto and more: among the most fiber-rich foods you can eat.

Notable for

Fiber, protein, folate, potassium, magnesium, iron.

Safety

Raw or undercooked kidney beans contain a lectin that causes severe stomach upset; proper boiling destroys it.

Gas

Fermentable fibers feed gut bacteria, producing gas; tolerance usually improves with regular intake.

Evidence & sources

• Cooked black beans provide about 9 g of protein and 9 g of fiber per 100 g. Evidence: established. Known: Measured food composition data. Unknown: Canned versions can contain added sodium. Source: USDA Agricultural Research Service, FoodData Central (SR Legacy) (2019).

Connected topics

• Fiber
• Protein
• Folate (B9)
• Potassium
• Gut Microbiome
• Food Safety Basics

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.