Of all nutrients groups, protein is arguably the most important. It is the basic building block in not only muscles but also the skin, hair and nails. It is an important component of the cell walls, a precursor to hormones and plays an important role in the transfer of oxygen in the blood and transcription of DNA. Proteins are made from a combination of more than 20 amino acids, nine of them are not produced by the body and must be obtained through diet. It is recommended that an average adult man eating at least 56 grams of protein daily (46 for women). This should come from a variety of the foods that are naturally high in protein
Foods derived from animals is the highest in quality protein. Meats such as beef, chicken, turkey and pork, contains 6.9 g of protein per oz. , About as much as found in one large egg. Dairy products, such as milk, cheese and yogurt, are all high in protein as well. In addition to the amount of protein, animal foods contain complete proteins, which means that they contain all the essential amino acids are not produced by the body. The problem with animal proteins is that they are also high in saturated fat. Too much reliance on animal proteins can lead to obesity and heart disease.
Although considered meat of most vegetarians, the nutritional quality of the fish significantly different from other animals. Tuna and salmon, for example, contains nearly as much complete protein such as chicken or pork, but with virtually no saturated fat. Instead, salmon, for example, is loaded with highly beneficial omega-3 fatty acids, vitamin D and various other nutrients. So, while the fish has any less total protein, generally, it is a healthier source of nourishment.
Nuts and seeds
As most vegetable sources of protein, nuts and seeds are not complete proteins. They need to be paired with grain to provide the essential amino acids they are missing. Nevertheless, they are loaded with amino acids they contain. Almonds, for example, contains four times as much protein as milk (8 grams per 1/4 cup). Peanuts have a bit more than that. Per 1/4 cup cashews contains 5g and pecans 2. 5 g. Seeds have similar protein content, with sunflower seeds contains 6 grams per 1/4 cup, pumpkin 8g and flaxseed 8 g. As fish, nuts and seeds are relatively low in saturated fat.
As nuts and seeds, legumes must be with whole grains, such as rice or bread, for creating a whole protein. Most beans contain about as much protein as peanuts and almonds. Soybeans contain about 14 grams of protein per half cup. A 1/2 cup serving of tofu, which is made from soybeans, contains about 10 grams of protein. Black beans, pinto beans and chickpeas contains about 7 grams per 1/4 cup.
One of the best kept secrets protein of the world is a South American vegetable called quinoa. Having all the advantages of vegetable protein sources, including low total calories and low in saturated fat, quinoa is also a complete protein similar in quality milk. Quinoa was prized by the Incas to increase stamina of their warriors. Today, quinoa is found in most health food stores, but has yet to become a mainstay of the American diet. The light, nutty flavor and slightly crunchy texture makes it an excellent substitute for couscous or rice, or as a standalone dish.