Protein: What are Proteins?
Proteins are an essential nutrient. Protein provides energy when not enough carbohydrate is available. Like carbohydrates, protein provides 4 calories per gram. Protein is contained in every part of the body, the skin, muscles, hair, blood, body organs, eyes, fingernails and bones. Protein is needed for growth, making muscle, tissue repair and aiding the body in fighting disease and infection. There is no life without protein. Next to water, protein is the most plentiful substance in the body.
Proteins are made up of small units called amino acids. Amino acids are identified as the building blocks of protein. There are 22 known amino acids. The body requires all 22 amino acids to meet its needs. The body has the ability to make some, but not all, of the amino acids needed to build proteins. Amino acids which can be made by the body are known as non-essential amino acids. Amino acids which can not be made by the body are known as essential amino acids. Since the body is not able to make the essential amino acids they must be provided from the protein foods consumed. Animal protein (such as meat, poultry, fish, milk and milk products and eggs) and plant protein (such as legumes, grains, vegetables, nuts and seeds) differ somewhat in the kinds of amino acids they contain.
Most animal proteins contain all the essential, also plenty of the non-essential, amino acids in liberal amounts. Therefore, they are identified as “complete proteins”. They can provide a balanced mixture of amino acids from their proteins that the body can use to meet its own needs. Besides protein, foods from this group supply a varying amounts of other important nutrients, including Iron, zinc, magnesium, Vitamin E, calcium and B vitamins (such as thiamin, niacin, and B6 and B12). Some of the foods in this group contain higher amounts of fats, saturated fat, and some cholesterol. Choosing the lower fat, lean, or extra lean cuts of red meats, poultry, and fish will promote an optimal cardiovascular health. Choosing a meat reduced in fat will not reduce the amino acid content of the meat, therefore; will not have an effect on the overall protein quality consumed.
The following are some helpful tips when making beef, poultry, and fish choices:
- beef – choose cuts with “loin” or “round” in the name (such as top round, round tip, top sirloin, bottom round, top loin, and tenderloin)
- ground beef – choose beef 92-95% lean or, ground round which is the leanest
- veal – choose cutlet, blade, arm steak, rib roast, and rib or loin chop
- look for “lean or “extra lean” cuts
- pork – choose cuts with “loin” or “leg” in the name (such as tenderloin, top loin roast, top loin chop, center loin chop, sirloin roast, loin rib chop)
- lamb – choose cuts with “loin” or “leg” in the name (such as leg, loin chop, arm chop and foreshanks)
- poultry – choose skinless white meat
- ground turkey – choose ground turkey breast
- fish – prepare grilled, baked, roasted, or boiled. Avoid deep fried, choose can fish in water
Proteins from plant sources are mostly “Incomplete proteins” in their natural forms. They contain small amounts of one or another amino acid. If a single plant protein is eaten by itself, the body can not take full advantage of it as a protein source. However, by combining two or more plant proteins that make up for each other’s deficiencies, a complete mix of all essential amino acids is provided to the body. These are called “complimentary proteins”.
Whole grains + legumes = complete protein
Whole Grain + White Bean
Whole grains + milk product = complete protein
Whole grain + Milk
Legumes + nuts = complete protein
Tofu Stir Fry + Cashew Nuts
Seeds + eggs = complete protein
Sunflower Seeds + Garden Salad