Types Of Food That Contain Protein

Dietary protein refers to the nine amino acids essential for health, including lysine, isoleucine, leucine, tryptophan, valine, methionine, phenylalanine, threonine and histidine, according to "The Natural Physician's Healing Therapies" by Mark Stengler. Without these essential proteins, the body will cease to function. There are other amino acids, but the body can manufacture them, given proper nutrition; these include taurine, arginine, glutamic acid, tyrosine, glutamine, glycine, cysteine, ornithine and proline. The recommended daily protein intake is 40g.

Foods Derived from Animals

Meats, like beef, chicken, lamb and fish, are the most effective sources of complete proteins. Beef is the most dense with complete proteins, containing 22 percent protein by volume. However, beef is also dense with fat, saturated fat and cholesterol, rendering it a less healthful than other sources of protein. Lamb contains fat and cholesterol in similar proportions, but chicken contains less, particularly when it's grilled without the skin. Fish contains the least protein of all meats, but its content is still substantial, at 20 percent by volume. It is also the most healthful, containing considerably less fat and no saturated far or cholesterol. Although not as dense in protein as meats, eggs are a protein-rich food. Comprised of 11.8 percent protein, two eggs will yield 12g of protein. Milk contains exclusive proteins, most notably caseins, which contain an amino acid complex suitable for the young, according to the University of Illinois.

Foods Derived from Plants

A variety of foods derived from plants, including seeds, beans, nuts, grains, peas and vegetables, contain incomplete proteins. Combining plant-derived foods can result in a meal that contains all nine essential amino acids, such as rice and beans, rice and corn and wheat cereal.

Soy and Spirulina

Soy contains protein, but it is controversial whether soy contains all nine essential amino acids. While some sources, like MedlinePlus, assert it does, other sources, like Stengler in "The Natural Physician's Healing Therapies" say it lacks methionine. Spirulina is an edible microscopic algae that exists in both fresh and salt water. Stengler indicates that it contains all nine essential amino acids; although it is more an additive than a food itself, it is markedly dense with protein, containing 3 to 5g of protein in 1 tbsp., according to NutritionalSupplements.