Whey or milk plasma is the liquid remaining after milk has been curdled and strained; it is a by-product of the manufacture of cheese or casein and has several commercial uses. Whey is used to produce ricotta and gjetost cheeses and many other products for human consumption. It is used as an additive in many processed foods, including breads, crackers and commercial pastry. In addition, whey is used as an animal feed. Whey proteins mainly consist of a-lactalbumin and ÃŸ-lactoglobulin. Depending on the method of manufacture, it may also contain glycomacropeptides (GMP). The whey protein separated from this mixture is often sold as a nutritional supplement. Such supplements are especially popular in the sport of bodybuilding. Liquid whey contains lactose, vitamins, and minerals along with traces of fat. Researchers at Lund University in Sweden discovered that whey appears to stimulate insulin release. Writing in the American Journal of Clinical Nutrition they also discovered that whey supplements can help regulate and reduce spikes in blood sugar levels among people with type 2 diabetes by increasing Insulin secretion.