Amino Acids

Better Nutrition, Sept, 1999 by Brenda Adderly

The building blocks of good health

Most people have heard of amino acids as "the building blocks of protein." But that description hardly does them justice. In fact, that phrase and several other terms used in discussions about amino acids have created considerable confusion about these vitally important substances.

A clarification of terms

"Essential" vs. "non-essential." For example, eight of the 28 existing amino acids are described as "essential" for adults (in children, the number is 10). In this case, though, the term essential is a bit misleading; actually, all the amino acids are essential -- as in an "important requirement" -- for good health. Those that receive the label "essential" are the ones that can only be obtained through food, while the so-called "non-essential" varieties are produced by the body.

"Building protein." Still more confusion comes from the notion that amino acids "build" protein. Most of us think of protein as food; but, in this case, the protein referred to is in our bodies. Protein is second only to water in terms of the most common substances in the human body. About 30 percent of our protein is found in our muscles, with the remaining amounts distributed among everything from our bones and skin to our blood and cartilage.

"Complete protein." Fish, poultry, and other meats, as well as dairy products and soy, all contain "complete protein," meaning the entire spectrum of amino acids in approximately equal amounts. Other foods -- like fruits, vegetables, and grains -- also contain amino acids. But because they don't have the full range, or certain acids are in short supply, they are considered "incomplete proteins." Of course, these proteins can be made complete by combining two or more of them, as in the case of beans and rice.

The creation of new protein from amino acids and the breaking down of existing protein into amino acids are on going processes in our bodies. If, for example, you are working out and developing certain muscles, amino acids come to the rescue with new protein to build muscle cells. Similarly, when you eat a complete protein, such as meat or beans and rice, the body breaks down the amino acids in that food for later use.

Checks & balances within the body

But what if one or more amino acids is missing? Then somewhere, somehow, a bodily function is likely to be thrown off balance. This imbalance could manifest itself as anything from depression, to an upset stomach, to obesity. And deficiencies can occur in people with poor diets as well as in people who eat nutritious meals, since stress, age, infection, and other factors can interfere with amino-acid availability.

Not only are the symptoms of amino-acid deficiencies wide ranging, but there are no RDAs, or other guidelines, to help us tell if we are at least covering all the bases. Add to that the complicated matter of keeping track of all 28 -- some with names most of us have never even heard -- and the situation begins to seem overwhelming.

Thankfully, it's net. By eating a healthful diet, rich in a variety of foods, it is likely that you are getting almost all of the amino acids you need.

Supplement forms are `free'

Amino acid supplements are available as "free form amino acids," which means they have been removed from the original source. Because they are no longer part of a food, they do not have to be broken down in the digestive system in order for the body to use them. For most of us, a supplement that provides a full range of amino acids is a good insurance policy, providing the building blocks of good health for our bodies and our minds.

REFERENCES

Cangiano, C., et al. "Effects of oral 5-Hydroxytryptophan on energy intake and macronutrient selection in non-insulin dependent diabetic patients," International Journal of Obesity and Related Metabolic Disorders 22(7):648-654, July 1998.

Johnston, Carol S., Solomon, R. Elizabeth, and Corte, Connne. "Vitamin C status of a campus population: college students get a C minus," Journal of American College Health 46(5):209, March 1, 1998.

Juhl, J. "Fibromyalgia and the serotonin pathway," Alternative Medicine Review 3(5):367-75, October 1998.

Following is a sampling of a few of the better-known substances in this "amino acid" category, and an overview of each one's abilities. ...

Arginine.

Benefits. A truly all-purpose substance, arginine affects everything from growth (making it one of the 10 "essentials" for children, but not for adults, whose bodies can synthesize it) to healing the skin, to liver detoxification, to enhancing the immune system.

Dietary sources. Arginine is plentiful in common foods, including dairy products, meat, peanuts, chocolate, and wheat. The only people who should avoid arginine and foods rich in the substance are those with herpes and similar viral infections. Arginine not only seems to encourage these viruses, but it also interferes with the anti-viral activity of another amino acid. lysine (see p. 58).

Dosage. Three to four grams of supplemental arginine is a reasonable amount to begin with. If there are no adverse effects, dosage can be increased to as much as 12 to 20 g; however, steady use of heavy doses has been linked to skin problems in some people.