There's More Than Turkey Behind Holiday Yawns

Mar. 23 --

THURSDAY, Nov. 22 (HealthDay News) -- Bleary eyes and nodding heads after the Thanksgiving feast aren't rare, and experts say a number of factors may make people drowsy during the holiday.

It may have to do with the traditional Thanksgiving meal, which includes items high in tryptophan -- a chemical known to promote sleepiness, said Donna Arand, clinical director of the Kettering Sleep Disorders Center in Dayton, Ohio, and research assistant professor at Wright State University Boonshoft School of Medicine.

"Turkey is particularly high in tryptophan, while milk and other dairy products also contain tryptophan," Arand said in a prepared statement. "L-tryptophan is an amino acid in the body that is used to produce serotonin, a brain chemical involved in REM sleep. Research has shown that an increase in L-tryptophan produces sedation and can shorten sleep latency. So, the sleepy feeling following a Thanksgiving dinner is probably the result of L-tryptophan."

The "sleep debt" accumulated by many people may also contribute to Thanksgiving torpor, said Ralph Downey III, chief of sleep medicine at the Sleep Disorders Center and Loma Linda University Medical Center in California, and an associate professor of psychology at the University of California at Riverside.

"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 said in a prepared statement.

"We nap or feel drowsy, because we are in a relaxed state. When we finally relax, our brain is primed for sleep from all the days when it has not had as much," he said. "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 sleep holiday," he said.

If you want to get a good night's sleep after your Thanksgiving celebrations, get exercise in the afternoon and don't eat a big meal too close to bedtime, advises the American Academy of Sleep Medicine (AASM).

More information

The National Sleep Foundation offers tips for healthy sleep.

SOURCE: American Academy of Sleep Medicine, news release, Nov. 12, 2007