Now there s a formula that combines two of nature s most effective diet aids to minimize the impact of dietary carbs and fats. Swanson Diet Duo is a revolutionary formula that combines the fat-binding power of LipoSan ULTRA chitosan with the carb-control capabilities of Phase 2 starch blocker. LipoSan ULTRA chitosan is a fiber supplement that promotes healthy weight management when combined with a healthy diet and exercise plan. While other chitosan products take up to two hours to work LipoSan ULTRA goes to work right away binding the fats in your diet before they bind to you. Phase 2 is a standardized white kidney bean extract that also promotes healthy weight management when combined with a healthy diet and exercise plan.