Have you ever finished Thanksgiving dinner, turned on the game and sat back onto your couch for a pleasant slumber?

It seems that sleeping is almost as much of a Thanksgiving Day pastime as the annual dinner or football game. These naps can be greatly attributed to the amount of food you eat – especially turkey, which contains the natural sedative tryptophan.

Tryptophan is an essential amino acid that the body does not manufacture itself, and it helps the body make the B-vitamin niacin, according to www.ehso.com. Niacin, in turn, helps the body produce serotonin, a chemical that acts as a claiming agent in the brain and plays a key role in sleep.

“I think of it as an urban legend,” said Kevin Schalinske, associate professor of food science and human nutrition in agriculture and life sciences. “The idea that tryptophan directly makes you sleep isn’t true. Overeating is just as likely to make you tired.”

Schalinske said that the tryptophan in turkey would only bring someone up to a normal level of serotonin and not start a complete overproduction that would make someone extremely tired.

Ralph Downey III, chief of sleep medicine at the Sleep Disorders Center at Loma Linda University Medical Center in Loma Linda, Calif., said that, while tryptophan can play a role in one’s feeling of sleepiness after a heavy Thanksgiving meal, it is also likely due to the sleep debt that the person has accumulated over a period of time.

“Thanksgiving and sleepiness go together like turkey and pumpkin pie. The sleepiness that we experience may be partly due to eating, but probably mostly because of the fact that we are relaxing with family and friends or watching the traditional parades and football games,” Downey wrote in an article for the American Academy of Sleep Medicine. “We nap or feel drowsy because we are in a relaxed state. It is probably much less the tryptophan in your turkey as it is the sleep debt built up in your brain that makes Thanksgiving a sleepy holiday.”