Tryptophan is another essential amino acid and is needed for the production of vitamin B3.  It enhances brain function by producing serotonin, which is a neurotransmitter, which transfers nerve impulses from one cell to another.  Serotonin is also responsible for creating in enhancing a normal sleep.  Tryptophan, by having an influence on the development of serotonin is considered in be able to combat depression and insomnia as well as to stabilize moods.  It can help to control hyperactivity in children, aid in weight control, promote the release of growth hormone, and promote a healthy heart.  It is been found to be helpful to migraines headaches and is known to have an neutralizing effect on the negative influence of nicotine.

Sources of tryptophna in food include:  cottage cheese brown rice soy protein, peanuts and meat.

In 1989 the federal government after surveying certain outbreaks of disease found a correlation betwen the outbreak of these diseases and the supplementation of L-tryptophan, with subsequent withdrawal of L-tryptophan supplements from the market.  Subsequent research indicated contaminants in the supplements were the actual cause of the disease outbreak.  However, L-tryptophan has still not been placed back on the martket.