Derived from milk, casein protein is actually a naturally more abundant source of branched-chain amino acids. Sometimes simply called “milk protein,” since around 80 percent of the protein found in cow’s milk is casein, and it is about 30 percent of human breast milk.
Casein, like whey and other protein foods, is made up of essential and non-essential amino acids. The human body is able to make certain amino acids on its own, the non-essential, while the remainder come from other foods you eat. Plant foods don’t always yield the complete set of essential amino acids we need.
Casein protein powder is produced in a lab by dehydrating parts of milk, the A2 beta-casein is preferred. Nutritional protein requirements increase the more active you become, and are especially high when you regularly lift weights or do other types of lengthy training. Supplementing workout diets with protein powders can increase net amino acid consumption for muscle-building while avoiding excessive calorie intake.
Casein protein has a lower percentage of branched-chain amino acid compared to whey protein, which is one reason it’s slower to digest and tends to work for longer. But, the difference has not been demonstrated to yield differences in athletic performance. So, consumers should base product choice upon: purity of product (percent of the product that is real the protein of interest), and net cost by weight.
Dried milk powder is simply milk from which the water has been removed. It has all the nutrients of milk except for vitamin C, thiamine and vitamin B12. The powder is 80 percent casein and 20 percent whey protein. Dried milk powder still contains lactose, unlike commercial casein and whey powders. Dried milk powder also costs significantly less than isolated casein or whey powders. Thereby, for those who are not lactose intolerant, the cost-efficient bodybuilder’s choice of protein boost, without other chemical enhancements, is powdered milk.