The third largest fragment of whey protein isolate derived from sweet whey is glycomacropeptide or GMP. However, GMP lacks the secondary structure necessary for it to be classified as a protein and is considered a long amino acid chain. These peptides are all soluble in water in their native forms, independent of pH. Major forms and uses There a majorly four types of whey protein that are commercially produced: Whey Protein Concentrates (WPC) have typically low - though not absent - levels of fat and cholesterol. They also contain carbohydrates in the form of lactose. Powders are typically between 29%–89% protein by dry weight. Whey Protein Isolates (WPI) are processed to remove fat and lactose, and as a result, WPI powders are typically over 90% protein by dry weight. Like WPC, WPI are mild and slightly milky in taste. Whey Protein Hydrolysates (WPH) are whey proteins that are predigested and partially hydrolyzed for the purpose of easier metabolizing. Their cost is generally higher than WPC or WPI. Highly hydrolysed whey may be less allergenic than other forms of whey, due to its much smaller and simpler peptide chains. For this reason it is a common constituent in hypoallergenic baby milk formulas and medical foods. Native whey protein is extracted from skim milk, rather than being collected as a byproduct of cheese production. This type of whey does not contain glycomacropeptide, which is formed only after the addition of rennet. There is evidence that whey protein is more bio-available than casein or soy protein. Whey protein is commonly marketed as a dietary supplement, typically sold in powdered form for mixing into beverages. Whey protein is also commonly used as a thickener to improve texture and decrease syneresis in many types of yogurt. Yogurt with high amounts of protein have been more commonly found on shelves due to the recently increasing popularity of Greek Yogurt. Use for strength training and muscle building The primary usage of whey protein supplements is for muscle growth and development. Eating whey protein supplements before exercise will not assist athletic performance, but it will enhance the body's protein recovery and synthesis after exercise because it increases the free amino acids in the body's free amino acid pool. In 2010 a panel of the European Food Safety Authority (EFSA) panel examined the effects on whey protein on weight loss (via both fat loss and increased satiety) and strength