Types of Protein
In the diet, protein sources are labeled according to how many of the essential amino acids they provide:
- A complete protein source is one that provides all of the essential amino acids. Animal-based foods; for example, meat, poultry, fish, milk, eggs, and cheese are considered complete protein sources.
- An incomplete protein source is one that is low in one or more of the essential amino acids. Complementary proteins are two or more incomplete protein sources that together provide adequate amounts of all the essential amino acids.
These proteins are commonly found in mammalian milk, making up 80% of the proteins in cows milk and between 20% and 45% of the proteins in human milk
As a food source, casein supplies amino acids, carbohydrate and the two inorganic elements calcium and phosphorus
Whey protein is isolated from whey, which is the liquid material created as a by-product of cheese production
Whey is an abundant source of branched-chain amino acids which are used to stimulate protein synthesis
Soy protein is a protein that is isolated from soybean
Soybean protein is a “complete protein” since it provides all of the essential amino acids for essential for human nutrition
SO HOW CAN I GET MORE PROTEINS?
Most meats and poultry and are good sources of protein
As meat can also be high in saturated fats, lean cuts of meat are better as they will contain less saturated fat
Protein is ALSO found in the following foods:
- meats, poultry, and fish
- legumes (dry beans and peas)
- nuts and seeds
- milk and milk products
- grains, some vegetables, and some fruits (provide only small amounts of protein relative to other sources)