Tryptophan

Monday, November 18, 2013

Youve been looking forward to Thanksgiving dinner all year turkey, mashed potatoes, cranberry sauce and pumpkin pie. But after you finish that second helping of turkey with gravy, you start to feel a little sleepy. Is it tryptophan in the turkey thats making you drowsy? Dr. Edward Hill tells us in todays 60 Second Housecall.

Dr. Hill:

Every Thanksgiving, tryptophan is blamed for many post-meal naps and drowsiness. Turkey contains a high level of this amino acid protein that is a precursor to a substance in your brain called serotonin. Serotonin is a neurotransmitter that improves your mood and can cause sleepiness.

While turkey does contain high levels of tryptophan, it also contains many other proteins. The tryptophan has to compete with all of these other turkey proteins and actually little tryptophan gets into the brain from eating turkey.

While isolated tryptophan can act as a sleep aid, tryptophan packaged with other amino acids does not have the same effect.

Most scientists think that theres a different reason why eating a special meal might make you drowsy. Eating a big Thanksgiving dinner causes increased blood flow to the stomach, needed to help digest the meal, and less blood flow to the brain.

Take a walk outside afterward to digest your meal. This will make you feel better than crashing on the couch.

For North Mississippi Medical Center, Im Dr. Edward Hill.