Optimum Nutrition Gold Standard 100% Whey Protein Supplement is one of the world's best-selling whey protein. Gold Standard 100% Whey Protein contains Whey Isolates (WPI) with a rated 90% pure protein - One of the purest and most expensive form of whey protein that exists. As a primary protein source, the Optimum Nutrition whey protein isolates squeeze an amazing 24 grams of the purest, muscle building protein available into each serving. Whey protein is essential to the growth of muscles, without the fat, cholesterol and lactose that is not necessarily required. These Optimum Nutrition protein supplements are absorbed into your system to aid muscle growth. Use first thing in the morning and/or during the 30 minutes just before or immediately after training. Each tasty serving of Gold Standard 100% Whey also contains 5.5g branched chain amino acids and only 1g of fat, sugar and 3g of carbs.