White Kidney Bean Extract

World Health Organization (WHO)

  • 2005 – 1.6 billion people are overweight
  • 2015 - 2.3 billion people projected to be overweight

Obesity is directly related to many causes of preventable death such as heart disease, stroke, diabetes and many other debilitating disorders such as musculoskeletal, joint, and liver disease. In most cases, obesity results from an excessive intake of fat and sugars from the diet which causes our bodies to store them as fat reserves.  The conversion of carbohydrates to simple sugars begins in the mouth through the amylase enzymes and continues in the small intestine through amylase and alpha-glucosidase enzymes. By inhibiting these enzymes, our body can no longer break down carbs, resulting in their elimination, lower blood sugar levels, and possibly weight loss.

People who suffer from Diabetes must restrict their carbohydrate intake in order to achieve optimal sugar levels. Glucosidase inhibitors are used for diabetic patients, usually combined with other treatments, and have been shown to lower blood glucose levels.

Obesity is directly related to Type 2 Diabetes and forms part of a syndrome known as Metabolic Syndrome. People with Metabolic Syndrome have an increased risk of heart disease.

Pharmaceutical companies have researched possible drugs that may reduce obesity with minimal side effects, but have yet to produce a safe and effective therapy.

The best treatment for obesity is a healthy and balanced diet, along with daily exercise. It’s known that 30 mins of exercise a day can significantly reduce the risk of heart disease.

White Kidney Bean Extract is a natural supplement that contains Phaseolamin, which blocks Carbohydrates from being converted into simple sugars in the stomach. Normally carbs are converted to sugars then stored as fat. White Kidney Bean Extract claims to block the conversion, therefore not allowing carbs to be absorbed.

There are many weight loss products for sale in the US  most of which have no scientific studies done to show weather they are beneficial or not. In this article, we will analyze the research behind White Kidney Bean Extract and provide medical insight on this product.

The active ingredient in White Kidney Bean Extract is known as Phaseolamin. The brand name is Phase 2.


Leiner Health Products; 2003.

Reduction in body weight with a starch blocking diet aid: StarchAway comparison with placebo.

A 12 week randomized double-blind placebo controlled trial that included 60 overweight individuals. Subjects consumed 2 chew tablets (500mg each) or placebo before each meal during 12 weeks.

Results: there was  statistically significant weight reduction in the active group compared with the placebo. The control group lost 6.9 ±7.9 lbs compared to the placebo group which gained 0.8 lbs ±6.1lbs.

Int J Med Sci 2007, 4:45-52

A dietary supplement containing standardized Phaseolus vulgaris extract influences body composition of overweight men and women.

A randomized, double-blind, placebo-controlled study was conducted with 60 overweight subjects. Participants took 1 tablet (active or placebo) per day for 30 consecutive days before meals.

Results: After 30 days, the active group had a significant reduction in body weight, BMI, fat mass, adipose tissue thickness and waist/hip/thigh circumferences while maintaining lean body mass. The control group lost an average of 6.45 lbs. There was also a 10.45% reduction in body fat compared with a 0.16% reduction in the placebo group (p < 0.001).

J Int Med Res 2000 28: 229-233

A randomized, double-blind, placebo-controlled trial of a new weight-reducing agent of natural origin.

A randomized double blind placebo controlled trial. Study included 40 overweight individuals that were required to take 2 tablets of Phaseolamin® (White Kidney Bean Extract) 650mg, 200 mg of inulin, and 50 mg of Garcinia cambogia extract each after each meal. The subjects were also instructed to follow a 1200 kcal/day low-fat diet.

Results: After 12 weeks, the active group had a significant reduction in weight, BMI and percent body fat compared to baseline, whereas there was no significant change in the placebo group. The active group lost an average of 7.7 lb, p = 0.001).

The Open Nutraceuticals Journal 2009, 2:88-91.

Investigation of an amylase inhibitor on human glucose absorption after starch consumption.

A placebo-controlled, cross-over study, eleven fasting subjects (men and women aged 21 to 57) were given 4 slices of white bread and 42 g (3 Tbs) of margarine with or without 1500 mg of Phase 2. Absorption and metabolism of carbohydrate was measured as levels of plasma glucose over time.

Results: the glucose levels following consumption of Phase 2 returned to baseline 20 minutes earlier. The authors concluded that this indicated that 1/3rd of the carbohydrate in the bread was absorbed.

Nutr J. 2009; 8: 52.

Lowering the glycemic index of white bread using a white bean extract.

A 6-arm crossover study was conducted with 13 randomized subjects to determine whether Phase 2 would lower the GI (glycemic index) of white bread. Testing was performed using capillary blood glucose measurements following ingestions of white bread with butter, with and without the addition of Phase 2 in capsule or powder form. Doses of 1500 mg, 2000 mg, and 3000 mg were used.

Results: 1500 mg dose had no effect on the GI and the 2000 mg and 3000 mg capsule doses caused insignificant reductions in GI. A reduction of over 34%.

Safety and Dosage

There have been no reports of any serious side effects associated with the use of White Kidney Bean Extract when used at recommended doses. Clinical efficacy trials have been done with doses of up to 3,000mg per day and for periods of up to 24 weeks with no reported adverse effects. The most commonly reported side effects are gastrointestinal symptoms such as flatulence and diarrhea, both of which aren’t serious. Some studies suggest that Phase 2 can be safe in doses of up to 10 grams a day, although there is little evidence to support these claims.

Dosage generally varies from 1,000mg to 3,000mg per day with best results observed at 3,000mg per day. Best results were seen with 1,000mg taken 3 times a day before each meal.


White Kidney Bean Extract (Phase 2) is a natural product that is routinely used for weight loss. There are numerous scientific trials on this product and all appear to reveal the same results. This product is beneficial for weight loss, and has been shown to lower glycemic index. Results are very conclusive, side effects are not serious, and for diabetic patients this product can produce a reduction in Glycemic Index. Best results are seen when combined with a lower caloric intake and lower carbohydrate intake.

Overall, I recommend this product for weight loss due to the overwhelming evidence that is available and the positive results that have been seen in multiple trials.

Thumbs up for weight loss.

Questions and Answers

How much weight can I expect to loose with White Kidney Bean Extract?

Results will vary depending on the diet and other lifestyle modifications. In general, expect to loose between 3 and 7 pounds a month. If combined with diet and exercise you can loose up to 15 pounds each month.

What are the side effects?

The most commonly reported side effects are flatulence and diarrhea. Both of which can cause a lot of discomfort. In some cases these side effects only appear during the first weeks of treatment and disappear.

How long can I take White Kidney Bean Extract for?

There is no known limit. Clinical trials generally last between 1 month and 3 months. Due to lack of information I would recommend a maximum of 3 months.

What are carbohydrates and why do they make me fat?

Carbohydrates are the most important source of energy for our body. Our body breaks down carbs in order to obtain sugars which provide energy to our cells. If we consume too many carbs we create reserves and essentially gain weight.

Whats the difference between “good” and “bad” carbs?

When we mention “good” carbs we are referring to complex carbohydrates. This means that they are harder to break down into sugar and contain more fiber. These are found in whole grain breads, cereals, and certain vegetables. 

The “bad” carbohydrates are those found in refined foods such as white bread, cakes, and cookies. These are easily converted to sugar and stored.