MedlinePlus Medical Encyclopedia: Tryptophan

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Tryptophan

Contents of this page:
Illustrations Definition	Information

Illustrations

Amino acids

Food guide pyramid

Definition Return to top

Tryptophan is an amino acid necessary for normal growth in infants and for nitrogen balance in adults. It is an essential amino acid, which means your body cannot produce it -- you must get it from your diet.

Information Return to top

The body uses tryptophan to help make niacin and serotonin. Serotonin is thought to produce healthy sleep and a stable mood.

In order for tryptophan in the diet to be changed into niacin, there needs to be enough vitamin B-6, riboflavin, and iron in the body.

Tryptophan can be found in:

Turkey
Chicken
Milk
Cheese
Fish
Eggs
Tofu
Soy
Sesame seeds
Pumpkin seeds
Nuts
Peanuts
Peanut butter

Update Date: 5/1/2006

Updated by: Caroline M. Apovian, M.D., FACN, Associate Professor of Medicine, Boston University School of Medicine and Director, Nutrition & Weight Management Center, Boston Medical Center, Boston, MA. Review provided by VeriMedHealthcare Network.

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