The Nervous System
Lesson 9, Page 12 of 19

True, while the so-called "bad fats," like trans fats, have a tendency to make cell membranes rigid, the "good fats," like lecithin, help keep them fluid.

5-HTP and Tryptophan

Tryptophan, or L-Tryptophan, is an essential amino acid. ("Essential" means that the body can't produce it—You must get it in your diet.) It is a very important precursor to the neurotransmitter serotonin. Individuals with certain mental disorders, such as depression, have been shown to have lower levels of serotonin in their brains. Some individuals who suffer from depression have found that they feel much better with tryptophan supplementation.

Tryptophan was also once widely used in the U.S. as a natural sleeping aid. There were also claims that it could reduce cravings for alcohol and other drugs and that it could be helpful in preventing panic attacks. In November of 1989, the FDA pulled all tryptophan off the U.S. market because of reports of individuals being poisoned by it. It turned out that these individuals were not poisoned by tryptophan, but by a contaminant that was found in one batch of tryptophan that came into the U.S. from abroad. However, the FDA, who has never been a friend of the food supplement industry, used this as an excuse to keep the product off the American market for years, probably because it was a very effective substitute for money-making drugs.

In recent years tryptophan has been allowed back on the market in the form of 5-HTP (5-Hydroxytryptophan.) 5-HTP is a very effective form of tryptophan—superior in fact to the forms that were previously on the market. 5-HTP is currently being used in the U.S. by many individuals to aid sleep, weight loss, and to improve mood in cases of minor to moderate depression. Unlike most drugs used to treat these conditions, 5-HTP seems to be without negative side-effects.

Which of the following is true about the amino acid Tryptophan?

It is an "essential" amino acid.
The body can't produce it.
It is a nutrient that must be in the diet.
It is available in the U.S. today in the form of 5-HTP.
All of the above.

(Select the best answer and click on the "Continue" button.)

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