Proteins are the main building blocks of the human body.
They’re used to make various important things, including tendons, organs and skin, as well as hormones, enzymes, neurotransmitters and various molecules.
Proteins are also the building blocks of the contractile elements in your muscles.
They’re assembled from amino acids, smaller molecules that are linked together like beads on a string.
Some amino acids are produced by your body’s cells, while others are supplied by the food you eat. The ones that you must get from foods are termed essential amino acids.
Proteins that supply all nine essential amino acids are the best, and whey protein is loaded with them.
It’s particularly high in important branched-chain amino acids (BCAAs) like leucine, and also contains a high amount of cysteine (7Trusted Source).
Studies show that leucine is the most anabolic (growth-promoting) amino acid, and cysteine can help boost levels of the cellular antioxidant glutathione (8Trusted Source, 9Trusted Source).
Whey protein appears to be particularly effective at stimulating growth in humans. In fact, human breast milk is 60% whey, compared to 20% in cow’s milk (10Trusted Source).
