Supplements
white kidney bean alpha-amylase inhibitor decreases body weight
In plain terms: Does white kidney bean "starch blocker" help you lose weight?
Yes — modest weight loss, but the active blocker is destroyed by baking and barely touches blood sugar.
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
White kidney bean extract (phaseolamin) modestly reduces weight/BMI/fat (MA: -1.62 kg) but is NULL on fasting glucose, insulin and TG — and the active alpha-amylase inhibitor is a heat-labile protein denatured by baking. Only viable as a co-consumed/post-bake standardized extract, never a dough ingredient; near-null on our glycemic endpoints.
The evidence (12)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Wang S, Chen L, Yang H, Gu J, Wang J, Ren F 2020 · Food Sci Nutr | RCT | supports | moderate | Regular WKBE intake produced greater average weight loss than placebo in matched overweight volunteers. |
| Celleno L, Tolaini MV, D'Amore A, Perricone NV, Preuss HG 2007 · Int J Med Sci | RCT | supports | moderate | 30-day DB-RCT: standardized P. vulgaris extract reduced body weight, fat, and waist vs placebo in overweight men/women. ↩ SUPERSEDED — pooled in the review above, counted once |
| Rahmanian R, Shaygantabar M, Hekmatdoost A, Nikparast A, Javaheri-Tafti F, Ghaeminejad Z, Khoshrang A, Hatami A, Mohammadi-Sartang M 2026 · Food Sci Nutr | meta-analysis | mixed | moderate | SR/MA non-soy legumes (incl. P. vulgaris) on body weight/composition: modest, heterogeneous effects; not uniformly significant. |
| Onakpoya I, Aldaas S, Terry R, Ernst E 2011 · Br J Nutr | meta-analysis | contradicts | moderate | MA: P. vulgaris extract gave non-significant weight loss vs placebo; poor-quality RCTs limit conclusions |
| Udani J, Singh BB 2007 · Altern Ther Health Med | RCT | supports | moderate | Fractionated white bean extract produced greater weight loss than placebo in a small clinical trial; carbohydrate-blocking mechanism. |
| Yan J, Zhao J, Naizemuding P, Zhao W, Sun J, Wang Y, Yang J, Li D, Zhang F, Cao H 2025 · Food science & nutrition | RCT | supports | low | 8-wk RCT, WKB α-AI extract (A10 strain) vs placebo: significant ↓ body weight, BMI, waist & hip circumference; no numeric Δ/CI or funding source given in abstract. |
| Payab M, Hasani-Ranjbar S, Shahbal N, Qorbani M, Aletaha A, Haghi-Aminjan H, Soltani A, Khatami F, Nikfar S, Hassani S, Abdollahi M, Larijani B 2020 · Phytother Res | meta-analysis | supports | moderate | MA: P. vulgaris significantly improved weight (SMD -0.88) in overweight/obese adults |
| Udani J, Hardy M, Madsen DC 2004 · Altern Med Rev | RCT | mixed | high | Phase 2 bean extract: no significant overall weight loss vs placebo at 8 wk; significant only in high-carbohydrate-consumer subgroup. |
| Singh SC, Singh H, Choudhary M 2024 · Heliyon | RCT | supports | moderate | DB placebo-controlled RCT n=66: Phaseolean WKBE 1500/3000 mg/d improved weight/anthropometrics vs placebo in overweight adults. |
| Jäger R, Abou Sawan S, Purpura M, Grube B, Röske Y, De Costa P, Chong PW 2024 · Sci Rep | RCT | supports | moderate | 12-wk Phase2 white kidney bean extract dose-dependently reduced body weight, fat mass, BMI vs placebo |
| Udani J, Tan O, Molina J 2018 · Foods | meta-analysis | supports | moderate | SR/MA of proprietary white-bean alpha-amylase inhibitor: significant weight loss vs placebo across pooled RCTs. |
| Shi N, Wang R, Cao X, Huang Z, Lin F, Xu R, Zhang Q 2026 · (SR/MA) | meta-analysis | supports | moderate | MA 8 RCTs n=543: weight -1.62 kg, fat -1.17 kg; glucose/insulin/TG NULL |
Disagree, or know a study we missed?
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.