BPI Sports Iso HD contains the purest, low-calorie, low-fat, low-carb protein delivering 25 grams of rapidly digesting 100% whey isolates. Best for those trying to lose weight and improve overall body composition. Protein is the building block of muscle. ISO HD contains 100% whey protein isolates that absorb quickly to help build and maintain lean muscle. As the building block of muscle, protein is also used in muscle repair. Since protein isolates are so pure, they digest and absorb quickly, allowing the body to put them to work in the recovery process faster. Protein is beneficial for those on a diet as it helps keep you full throughout the day. This may reduce cravings and excess calorie intake, resulting in weight loss. ISO HD is particularly beneficial due to the low-carb, low-calorie formula with zero sugar.