Protein is an essential component of human life, making up some 20 per cent of our total body weight. It is a significant constituent of all body cells, functioning both in their growth, as well as maintenance and repair. Additionally, protein acts as a regulatory substance, involving most of the body’s required functions: from antibodies to enzymes, and a good many hormones. All are classified as protein.

      Protein is made of up chains of amino acids, linked together in specific sequences predetermined by our genes. The order, and number of amino acids determine the specific role a particular protein plays in the body. There are a total of 22 amino acids, 13 of which can be manufactured by the body on its own. The remaining 9 do not occur naturally, and are provided from dietary sources. It is for this reason that dietary protein is so important for the normal functioning of many bodily processes. The 9 essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.
      From a dietary standpoint, all protein is not alike. Nutritionists generally describe dietary protein as either complete or incomplete. That is, either it contains the 9, so-called essential amino acids, or it does not. We cannot survive on incomplete protein alone because, by definition, one or more of the 9 essential amino acids are missing... and all are required for the complete synthesis of the body’s required protein.

      Complete protein is generally found in animal foods, including meat, fish, poultry, and dairy products. Protein from many common vegetable foodstuffs, such as grains and various types of beans, is of the incomplete variety. It is possible to combine certain incomplete protein with other incomplete protein and, if consumed in the same meal, let the body manufacture the missing essential amino acids. So, strictly speaking, a true vegetarian can get by without eating animal products... if they know exactly what they are doing, and how to combine incomplete protein from “complementary” food sources. As to strict vegetarian diets, there are numerous concerns other than just protein, the absence of vitamin B12 to name one.

      What happens if you do not consume enough protein containing all of the required amino acids? Your body will be missing one or more of the essential building blocks and you will begin to suffer muscle and tissue loss and, if prolonged, critical bodily functions will break down. The amount of protein required on a daily basis for good health is dependant on body weight. The Recommended Daily Intake of protein for adults of average height and weight is approximately 58-63 grams for males, and approximately 46-50 grams for females.
      Your specific needs can be determined from the protein requirement calculator below. Again, this is an approximation, and keep in mind that children and adolescents require slightly more protein per pound than adults per day.

Enter your weight in the first box and click "calculate."

lbs kg     grams protein/day

      Like most things related to the diet, it is possible to consume too much protein. The negative effects are, in some cases, indirect, but still potentially damaging to overall health. As mentioned, dietary protein supplies the amino acids required for protein synthesis. The body cannot store excess amino acids, so any that are not used contribute to energy stores, or to fat surplus. Additionally, excess protein translates into excess calories, excess cholesterol, excess fat, and ultimately excess urinary waste products, all of which place an overload on respective areas of the body.