Tryptophan

Definition

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

Function

The body uses tryptophan to help make niacin, melatonin, 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, the body needs to have enough:

  • Iron
  • Riboflavin
  • Vitamin B6

Food Sources

Tryptophan can be found in:

  • Cheese
  • Chicken
  • Egg whites
  • Fish
  • Milk
  • Sunflower seeds
  • Peanuts
  • Pumpkin seeds
  • Sesame seeds
  • Soy beans
  • Turkey

Images

Amino acids
Food guide pyramid

References

Murray MT. 5-Hydroxytryptophan. In: Pizzorno JE, Murray MT, eds. Textbook of Natural Medicine. 4th ed. St Louis, MO: Elsevier Churchill Livingstone; 2013:chap 98.

United States Department of Health and Human Services; United States Department of Agriculture. 2015-2020 Dietary Guidelines for Americans. 8th ed. health.gov/dietaryguidelines/2015/guidelines/. Updated December 2015. Accessed April 17, 2018.

Review Date: 
1/13/2018
Reviewed By: 
Emily Wax, RD, The Brooklyn Hospital Center, Brooklyn, NY. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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