BACK
TO
TOP
Browse A-Z

Print-Friendly
Bookmarks
bookmarks-menu

Tryptophan

Tryptophan is an amino acid needed for normal growth in infants and for the production and maintenance of the body's proteins, muscles, enzymes, and neurotransmitters. 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 melatonin and serotonin. Melatonin helps regulate the sleep-wake cycle, and serotonin is thought to help regulate appetite, sleep, mood, and pain.

The liver can also use tryptophan to produce niacin (vitamin B3), which is needed for energy metabolism and DNA production. 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

References

Nagai R, Taniguchi N. Amino acids and proteins. In: Baynes JW, Dominiczak MH, eds. Medical Biochemistry. 5th ed. Philadelphia, PA: Elsevier; 2019:chap 2.

United States Department of Health and Human Services; United States Department of Agriculture. 2015-2020 Dietary Guidelines for Americans. 8th ed. health.gov/our-work/food-nutrition/2015-2020-dietary-guidelines/guidelines/. Updated December 2015. Accessed May 27, 2022.

  • Proteins - illustration

    Protein is an important nutrient that builds muscles and bones and provides energy. Protein can help with weight control because it helps you feel full and satisfied from your meals. The healthiest proteins for weight maintenance are the leanest, meaning they have less fat and calories than other choices. The leanest protein choices are fish or shellfish, skinless chicken or turkey, low-fat or fat-free dairy (skim milk, low-fat cheese). The leanest red meat cuts are loin and tenderloin. Other healthy options are plant-based proteins.

    Proteins

    illustration

  • Amino acids - illustration

    Amino acids are either essential, which must be supplied by food, or nonessential, which are made in the body.

    Amino acids

    illustration

  • Proteins - illustration

    Protein is an important nutrient that builds muscles and bones and provides energy. Protein can help with weight control because it helps you feel full and satisfied from your meals. The healthiest proteins for weight maintenance are the leanest, meaning they have less fat and calories than other choices. The leanest protein choices are fish or shellfish, skinless chicken or turkey, low-fat or fat-free dairy (skim milk, low-fat cheese). The leanest red meat cuts are loin and tenderloin. Other healthy options are plant-based proteins.

    Proteins

    illustration

  • Amino acids - illustration

    Amino acids are either essential, which must be supplied by food, or nonessential, which are made in the body.

    Amino acids

    illustration

 

Review Date: 2/4/2022

Reviewed By: Meagan Bridges, RD, University of Virginia Health System, Charlottesville, VA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
© 1997- adam.comAll rights reserved.

 
 
 

 

 

A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.
Content is best viewed in IE9 or above, Firefox and Google Chrome browser.