Phaseolamin is an alpha-amylase inhibitor derived from white kidney beans (Phaseolus vulgaris). Its use for weight loss is based on its ability to inhibit the enzyme alpha-amylase, which breaks down dietary starches into simple sugars for absorption. By blocking this enzyme, phaseolamin is believed to reduce carbohydrate digestion and, consequently, calorie absorption, potentially supporting weight loss efforts.

Several small clinical studies and meta-analyses have investigated the effects of phaseolamin supplements on weight loss. Some randomized, placebo-controlled trials have found statistically significant, yet modest, reductions in body weight and body fat among overweight or obese individuals taking phaseolamin compared to placebo. For instance, a meta-analysis published in Obesity (Silver Spring) in 2011 found that products containing white kidney bean extract resulted in small but significant reductions in body weight over 4-12 weeks. However, the overall quality of evidence is limited by small sample sizes, short study durations, and potential biases in study design. Adverse effects are generally mild, such as gastrointestinal discomfort.

In summary, there is some scientific evidence supporting the use of phaseolamin for weight loss, but the effects appear to be modest and the quality of evidence is not strong. More rigorous, long-term studies are needed to clearly establish its efficacy and safety.