White Kidney Bean Extract

Commonly used for
Weight Loss
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What is it? / Overview
The extract inhibits salivary and pancreatic alpha-amylase, slowing the breakdown of complex carbohydrates so fewer are absorbed as glucose -- effectively reducing calorie extraction from starchy food. Multiple RCTs and a 2026 meta-analysis show a real, if modest, weight and waist-circumference reduction, generally below the ~2.5 kg threshold usually considered clinically significant on its own.
How is it used? / Administration
Form: Phaseolus vulgaris (white/navy bean) aqueous extract standardized to alpha-amylase-inhibitor activity (e.g. Phase 2, Phaseolean)
Typical dose studied: ~1,000-1,500 mg before carbohydrate-containing meals, 2-3 times daily
Timing: ~30 minutes before starchy meals -- this is the mechanism that matters (a 'carb blocker')
GI effects (flatulence, loose stools) are the main tolerability issue -- from undigested starch reaching the colon, consistent with the mechanism.
How well does it work? / Evidence
~ Moderate evidence
Who should avoid it?
Interacts with: Acarbose -- overlapping alpha-amylase-inhibiting mechanism, theoretical additive GI effects
Already taking it? The most consistently supported weight-management item in this batch -- reasonable to continue, but calibrate expectations to a real but modest 1-2 kg effect that only shows up alongside an actual calorie-controlled, carbohydrate-containing diet.
Research & references
Jäger R et al. (2024). Proprietary Alpha-Amylase Inhibitor Formulation From White Kidney Bean (Phaseolus Vulgaris L.) Promotes Weight and Fat Loss. Scientific Reports. Shi N et al. (2026). White Kidney Bean Extract Reduces Body Weight and Adiposity With Acceptable Safety in Adults With Overweight and Obese. Nutrition Research.
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