Natrol’s Phase 2, Carb Intercept, White Kidney Bean Extract, is a clinically tested complex. This complex is a non-stimulant natural carbohydrate blocker that works by stopping the digestion of carbohydrates. Carbohydrates, or carbs, are a necessary part of everyone’s diet, but too many carbohydrates are often blamed for causing weight gain. Phase 2 White Kidney Bean Extract is the first carbohydrate “blocker” that is clinically proven to delay the digestion of carbohydrates, which reduces the caloric impact of “starchy” foods. These carbohydrates or “starchy” foods include breads, cereals, pasta, rice, and starchy vegetables.