In the world of fitness, there is much discussion about the importance of getting supplemental protein for building muscle. What that outside fitness often does not realize is the importance of protein supplements for other reasons, such as medical treatment recovery.

Protein is composed of amino acids, which are important for good health. Protein is a significant component of proper nutrition and helps the body repair cells, muscles and bones. Protein helps control the metabolism processes.

Medical and scientific studies have shown that when the body is under stress, such as from an intense fitness regime or fitness, it needs more protein than can be obtained from food. Other sources of stress for your body include surgery, illness, or medical treatments such as chemotherapy or radiation therapy.

Of course, it is always important to include protein-rich foods in your diet. These are foods like eggs, fish, poultry, meat, legumes and dried beans. In stressful situations, however, your body requires protein supplements. The question most people have is which is the best protein or fitness supplement?

Medical and scientific studies show that 100% whey protein is superior to other forms of protein in promoting muscle building and providing immune system support. Proteins in foods are not the same and they can vary in aspects like the number and amount of essential amino acids, rates of digestion and absorption, taste, fat content and purity. On every commonly-used scale of protein quality, whey protein is noted as an excellent, high-quality source of protein.

Whey protein comes from cow's milk. Of the two proteins in milk - casein and whey protein - the whey protein constitutes about 20% of the total. Whey protein is the more soluble of the two and rates higher for protein quality. The best whey protein, 100% whey, is the most nutritious form of protein available.

But not all whey proteins are alike. Two main forms of whey protein are available and it is important to know the difference between them. Whey protein isolate is the most concentrated and best whey protein available. It is 90% or more protein and very little fat or lactose. Whey protein concentrate is between 30% and 89% protein, and the remainder is fat and lactose.

Whey protein is a by-product of the cheese-making process. In the cheese-making process the milk fat and casein are separated from the liquid whey. The best whey protein isolate is obtained by filtering the liquid whey and removing the lactose and fat. The filtered whey liquid is dried and what remains is whey protein.

Whey protein isolate is carefully separated and filtered; it is naturally low in fat and lactose. This makes it safe for most people who suffer from lactose intolerance and for those trying to lose weight. Whey protein is best used as part of a protein shake, taken between meals. It is important not to include fruit juice or sugar in your protein shake, since protein is not absorbed well in the presence of sugar. Milk, yogurt and sugar substitutes are part of an effective protein shake.

So where can you buy 100% whey protein? The best whey protein, 100% whey protein, is not for sale from most retail outlets. To reduce costs and product prices, most brands blend proteins of different concentrations into their products. The true 100% whey protein, one of the best whey protein powders on the market, is not available in retail stores. The good news is 100% whey protein is available for sale online.