365: Chemistry for Life
DAY 328

Tryptophan

Although the amino acid, tryptophan, is especially associated with turkey, it is actually present in many every-day foods including poultry, eggs, cheese, meat, and fish.

Credit: iStock

The holiday of Thanksgiving celebrates the chemistry of human relationships perhaps more than any other, especially since there are no gifts involved. Extended families squeeze around a too-small table using chairs pressed into service from all around the house to share gratitude for love, affection, and togetherness. Even those of us who have at some point found ourselves to be “Thanksgiving orphans” whose families are gone or are too far away to travel have been taken into the hearts and homes of friends so we may share in the celebration of family and community.

Thanksgiving Day starts for some with an early wake-up call, either to watch the holiday parade or to start cooking. Ah the food. The centerpiece of the day and Thanksgiving’s enduring symbol is most certainly the turkey, which seems to have acquired a certain chemical mystique of its own as an unusually good source of the amino acid tryptophan.

Tryptophan is one of the 20 amino acids that are used as the building blocks for biosynthesis of proteins. Eight of these 20 including tryptophan are labeled “essential,” indicating that the body does not have the ability to synthesize these substances. Instead, they come from the food that we eat such as red meat, fish, poultry, eggs, chocolate, and pumpkin seeds.

Tryptophan is a vital component in synthesizing a number of other biomolecules in the body, such as the vitamin, Niacin, which plays an important role in converting food to energy in the body as well as maintaining healthy skin, the digestive system, and nerves. Serotonin, a neurotransmitter known to contribute to feelings of well-being and happiness, is also made starting with tryptophan. 

Serotonin (from tryptophan) is also used to make melotonin, which helps control the body’s sleeping and waking cycles, and may be why the Thanksgiving turkey often gets the blame for that other great holiday tradition: an afternoon snooze during the football game. Since the amount of tryptophan found in turkey is no more than other poultry, the large quantities of carbohydrates such as bread, potatoes, and the all-important pumpkin pie that are consumed as part of the day’s celebration are more likely the contributors to that holiday nap.

More information about tryptophan may be found at http://www.webmd.com/food-recipes/features/the-truth-about-tryptophan.