Twenty percent of the human body is made up of protein, and proteins play an important part in building and maintaining our body tissue, as well as providing energy. Because of these facts, protein must be a major part of any healthy diet. They are the building blocks of a healthy body, and amino acids are the building blocks of protein. A diet low in protein will lead to protein-energy malnutrition. And the most important characteristic of protein, when viewed from a nutritional standpoint, is its amino acid composition.
There are a large number of amino acids, but nine of these are considered as essential amino acids, meaning that our bodies cannot synthesize on their own. These are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine,lysine, and histidine. There are an additional six amino acids which, under certain adverse conditions, such as premature birth or catabolic distress, meaning that the body is breaking down body tissue in an abnormal fashion, cannot be synthesized. These so called non-essential amino acids are arginine, cysteine, glycine, glutamine, proline, and tyrosine. There is also a third group, called dispensable amino acids because they are synthesized in the human body, consisting of alanine, aspartic acid, asparagine, glutamic acid, and serine. All of the amino acids are needed to ensure our continued good health, with children over the age of three years needing 10 to 20 percent more than adults.
There are a variety of readily available sources for these amino acids. The primary sources for most of us will be in animal products such as meat, fish, dairy product, and eggs. Vegetarians and vegans can obtain a sufficient of the essential amino acids from various grains, legumes, and nuts. It is a commonly held belief that athletes, in order to maintain peak physical performance levels, require a higher intake of amino acids.
But the way protein is used in our bodies is a complex operation. When we consume protein, this is broken down in our gastrointestinal tract into the various amino acids. These substances are then transformed into new protein material and amino acids, as needed, by a process known as biosynthesis. But if you do not consume enough protein, or the proper type of protein, this process cannot be effective. Sometimes, our intake of protein, and amino acids, can be compromised. Pollution due to fossil fuels, hormones used in cattle, fertilizers in farming, and the vast amounts of processing our food undergoes in the modern world can adversely affect the quality and quantity of amino acids found in our diet. Nutritional supplements have proven effective in supplying the correct amount and type of amino acids which our body requires.
While the elderly may be at particular risk, young, healthy individuals may also be affected by an amino acid deficiency. Symptoms include everything from diabetes, high blood pressure and high cholesterol, hair loss, weight gain, and arthritis to erectile problem, menopausal complaints, sleep disorders, and mood swings.
Amino Acids: What are they? What do they do?