The Best Protein Food Sources

Protein is an important energy-yielding macronutrient, or a nutrient needed in large quantities. Protein is necessary to form the structure of cells, tissues and muscles. The building blocks of protein, amino acids, are important for manufacturing enzymes and hormones. Nearly every food has some protein, but the best food sources are complete protein foods, or those that provide all nine essential amino acids, such as meat or animal-derived products.

Meats, Fish and Poultry

Meats such as lean ground beef, sirloin or round steak are excellent protein sources, as are game meats such as venison and bison. Pork products such as pork tenderloin, ham and pork chops are also rich in protein. All varieties of poultry are high in protein. Examples include chicken breasts, legs or thighs and turkey or duck breast meat. Fish is a lean, high-quality protein source. Varieties such as tuna, halibut, salmon, whitefish, swordfish and cod, as well as shellfish, mollusks and crustaceans are protein-rich. According to the Mayo Clinic website, each ounce of beef, pork, poultry or fish provides 7 g of protein.

Dairy Products and Eggs

Dairy products are also animal-derived foods, thus they provide all nine essential amino acids and are rich in protein. Milk, cheese and yogurt are especially good protein sources. According to the Common Sense Health website, one cup of milk provides 8 g protein, 1/2-cup of low-fat cottage cheese provides 16 g protein and an 8-oz. cup of yogurt offers between 12 and 13 g protein. Eggs are rich in protein, particularly egg whites. One egg offers just over 6 g protein.. According to the Mayo Clinic website, one ounce of American, bleu, Brie, cheddar, hard goat, monterey jack or Swiss cheese provides 7 g protein.

Soy and Quinoa

Soy products, such as tofu, soybeans and soy milk are all rich in protein and provide all nine essential amino acids. A 1/2-cup serving of fresh tofu provides 10 g protein and 1/2-cup of cooked soybeans provides 11 g protein, according to the Mayo Clinic website. According to, one cup of soy milk provides 10 g protein. According to the Soy Foods Association of North America, one ounce of plain soy protein isolate powder provides 23 g protein, and according to the Vegetarian Resource Group, quinoa, a grain-like crop with edible seeds, is a complete protein vegan food. One cup of cooked quinoa provides 9 g protein.

Other foods such as starchy beans, dried peas, nuts, nut butters and seeds are also protein-rich. These foods do not contain all essential amino acids, and a person should pair them with other plant or animal foods in his diet.

About this Author

Michele Turcotte is a registered, licensed dietitian, and a certified personal trainer with the National Academy of Sports Medicine. She has more than 12 years of experience in clinical and corporate settings, and has extensive experience in one-on-one diet counseling and meal planning. She has written freelance food and nutrition articles for Trouve Publishing Inc. since 2004.