Phase 2 Carb Controller Proprietary Blend
Also known as: Phase 2 Carb Controller Proprietary Blend, White kidney bean extract, Alpha-amylase inhibitor from beans, Phaseolus vulgaris extract
Overview
Phaseolus vulgaris extract, commonly known as white kidney bean extract, is the primary active ingredient in supplements marketed as 'Phase 2 Carb Controller'. This extract contains alpha-amylase inhibitors, specifically the alpha-AI1 protein, which reduces the enzymatic breakdown of complex carbohydrates (starches) into simpler, absorbable sugars in the gastrointestinal tract. By inhibiting alpha-amylase, it aims to decrease the absorption of dietary starches, thereby reducing caloric intake from carbohydrates and mitigating postprandial blood glucose spikes. It is primarily used as a carbohydrate absorption inhibitor for weight management and to support glycemic control, particularly in individuals with impaired glucose tolerance or as an adjunct in managing type 2 diabetes. The extract is typically standardized to a specific alpha-amylase inhibitory activity, often ranging from 3000-5000 IU/g, ensuring consistent potency. Research on its efficacy is moderate, with several randomized controlled trials and meta-analyses supporting its effects, though study heterogeneity exists.
Benefits
Phaseolus vulgaris extract offers several evidence-based benefits, primarily related to carbohydrate metabolism and weight management. Studies have shown a reduction in postprandial blood glucose, with some trials indicating a decrease in glucose peaks by approximately 10-20% after starch-rich meals. This effect is beneficial for individuals looking to manage blood sugar levels. For weight loss, meta-analyses report modest but statistically significant effects, typically around 1-2 kg over 4-12 weeks compared to placebo. While the weight loss effect size is small to moderate, it can be a useful adjunct to lifestyle changes. Secondary benefits include a potential reduction in insulin spikes and improved insulin sensitivity, though these effects are not consistently demonstrated across all studies. It is particularly beneficial for individuals who are overweight or obese, and those with impaired glucose tolerance or mild type 2 diabetes may experience improved glycemic control. The effects on postprandial glucose are acute, occurring within hours, while weight loss benefits typically require at least four weeks of consistent use. The quality of evidence is moderate, with several high-quality RCTs and meta-analyses supporting these claims.
How it works
Phaseolus vulgaris extract primarily functions as a competitive inhibitor of pancreatic alpha-amylase, an enzyme crucial for breaking down complex carbohydrates (starches) into simpler sugars in the small intestine. By binding to alpha-amylase, the extract prevents the enzyme from hydrolyzing starches into absorbable maltose and glucose. This inhibition leads to a reduction in the digestion and subsequent absorption of dietary starches. Consequently, fewer glucose molecules enter the bloodstream, which can lead to lower postprandial blood glucose levels and reduced insulin demand. The active components of the extract act locally within the gastrointestinal tract and are not significantly absorbed into the systemic circulation, ensuring its effects are confined to the digestive process.
Side effects
Phaseolus vulgaris extract is generally considered safe with a low incidence of adverse effects when used at recommended dosages. The most common side effects, affecting over 5% of users, are gastrointestinal in nature. These include flatulence, bloating, and mild diarrhea. These symptoms occur because undigested carbohydrates pass into the large intestine, where they are fermented by gut bacteria, producing gas. Less common side effects, affecting 1-5% of users, include general abdominal discomfort and mild nausea. Rare side effects, occurring in less than 1% of individuals, primarily involve allergic reactions, particularly in those with pre-existing legume allergies. There are no significant drug interactions reported, but caution is advised when combining it with antidiabetic medications due to the potential for additive hypoglycemic effects, which could lead to excessively low blood sugar. Contraindications include known allergies to legumes or Phaseolus vulgaris, and individuals with pre-existing gastrointestinal disorders like irritable bowel syndrome (IBS) may experience an exacerbation of their symptoms. Data on its use in pregnant or breastfeeding women is limited, so it is not recommended without medical supervision.
Dosage
The minimum effective dose of standardized white kidney bean extract is approximately 500 mg per carbohydrate-containing meal. The optimal dosage ranges from 500 mg to 3000 mg per day, typically divided into doses taken immediately before or with meals that contain significant starch content. For instance, a common recommendation is 500-1000 mg before each major meal. The maximum safe dose is generally considered to be up to 3000 mg per day, with higher doses potentially increasing the likelihood and severity of gastrointestinal side effects such as flatulence and bloating. The extract is most effective when taken just prior to or concurrently with the meal to ensure the alpha-amylase inhibitors are present in the digestive tract when starches are consumed. It is typically available in capsule or tablet form, standardized for its alpha-amylase inhibitory units. Since the active components act locally in the gut and are not systemically absorbed, factors related to systemic absorption are not relevant for its efficacy.
FAQs
How quickly will I see results?
Effects on postprandial blood glucose are acute and can be observed within hours of ingestion. Weight loss benefits typically require consistent use for at least 4-12 weeks.
Can it replace diet and exercise?
No, Phaseolus vulgaris extract should not replace diet and exercise. Its benefits are modest and it is best used as an adjunct to a healthy lifestyle for weight management and glycemic control.
Is it safe for long-term use?
It is generally considered safe for long-term use, but most studies are short-to-medium term. Mild gastrointestinal side effects may persist with continuous use.
Will it cause digestive discomfort?
Some users may experience mild gastrointestinal symptoms such as flatulence, bloating, or mild diarrhea, especially at higher doses, due to undigested carbohydrates fermenting in the colon.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/15159656/ – This randomized, double-blind, placebo-controlled study investigated the effects of Phaseolus vulgaris extract on body weight and fat mass in overweight adults over 30 days. It found a significant reduction in body weight (approx. 1.5 kg) and fat mass in the group receiving the extract compared to placebo, suggesting its potential for weight management. The study was well-controlled but had a small sample size and short duration.
- https://pubmed.ncbi.nlm.nih.gov/21876123/ – This systematic review and meta-analysis, published in the Cochrane Database, synthesized data from 6 RCTs involving over 200 participants. It concluded that Phaseolus vulgaris extract led to a mean weight loss of 1.08 kg compared to placebo and noted reductions in postprandial glucose. The review highlighted the small sample sizes, variable extract standardization, and short follow-up periods of the included studies as limitations, indicating a moderate risk of bias.
- https://pubmed.ncbi.nlm.nih.gov/19895910/ – This acute, single-meal randomized controlled trial in 60 healthy adults examined the effect of Phaseolus vulgaris extract on postprandial blood glucose. It demonstrated an 18% reduction in the area under the curve (AUC) for postprandial blood glucose after a starch-rich meal. While the study had a good methodology, its acute nature and small sample size limit the generalizability of its findings to long-term effects.
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