But eating loads of turkey, or any tryptophan-rich food for that matter, does not boost melatonin production, Wurtman says. Situated outside the blood–brain barrier, the pineal gland has ready access to blood tryptophan, which it uses to make serotonin. In contrast to how this neurotransmitter functions in the brain, however, pineal serotonin is just a chemical precursor of melatonin; subsequent biochemical reactions in this gland are necessary to convert it to melatonin.
After a turkey meal, blood levels of tryptophan rise, which may amplify the pineal's production of such serotonin, but not melatonin, whose synthesis rate depends on the amount of enzymes available for the subsequent biochemical reactions to occur, Wurtman says.
If turkey is not the culprit, then what besides dessert causes post-Thanksgiving torpidity? It may simply be a function of scarfing down enormous quantities of food.
"Studies have indicated that stretching of the small intestine induces sleepiness and a protein–fat loading of the stomach induces sleepiness," says biologist H. Craig Heller at Stanford University in Palo Alto, Calif., "and, more blood going to the gastrointestinal tract means less going elsewhere,"—for example, the brain or skeletal muscle.
"Also, there is the general phenomenon of parasympathetic tone—rest and digest—that is conducive to sleep," Heller says. Working in opposition to the sympathetic "fight or flight" stress response, the parasympathetic nervous system restores and conserves energy by reducing heart rate and blood pressure while increasing salivation and gastric action for digestion.
Don't forget the beverages either. Thanksgiving feasts are often washed down with bubbling champagne, beer, wine or other spirits. Despite the latter's name, all have a lulling affect on the mind and body. So don't blame the turkey for your postprandial lethargy, instead give thanks for the abundance of drink and carbohydrate-rich, albeit slumber-inducing fare.
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7 Comments
Add CommentYou may want to check your history. The first Thanksgiving was held in Virginia in 1619. I'll be watching for your correction.
Reply | Report Abuse | Link to this"Though the earliest attested Thanksgiving celebration was on September 8, 1565 in what is now Saint Augustine, Florida, the traditional "first Thanksgiving" is venerated as having occurred at the site of Plymouth Plantation, in 1621."
Reply | Report Abuse | Link to thisIf people are going to make comments on articles, they should provide where they got their sources, and double check their work. While Wikipedia isn't a credible source, I can assure you the first Thanksgiving wasn't held in 1619, and that the most famous one was in fact in 1621. More info to come later if someone should challenge what I've said.
How can u people NITPICK when it's almost time to eat TURKEY?!?
Reply | Report Abuse | Link to thiscookies 453 yea you shutttt upppp
Reply | Report Abuse | Link to thisI have read this article and I am not impressed with this logic. I made a turkey (outside t-day) and every time I eat a sandwich or turkey salad, I have to lie down. I cant even force myself to stay awake. If I was driving I would have to pull over. I have proved this over and over. I am not talking just a 10 min nap. I am talking, feeling like I have taking an overdose of sleeping pills. Why, is this? Chicken don't cause this. When I eat turkey I have to make sure I don't need to be anywhere.
Reply | Report Abuse | Link to thisI have read this article and I am not impressed with this logic. I made a turkey (outside t-day) and every time I eat a sandwich or turkey salad, I have to lie down. I can’t even force myself to stay awake. If I was driving I would have to pull over. I have proved this over and over. I am not talking just a 10 min nap. I am talking, feeling like I have taking an overdose of sleeping pills. Why, is this? Chicken don't cause this. When I eat turkey I have to make sure I don't need to be anywhere.
Reply | Report Abuse | Link to thisThanks. I was looking for an article on this. If there were a large sample of persons who were studied who ate just turkey as opposed to a control group who had another diet, it might be interesting to see what affect that has on sleep. I'm wondering about the proportion of tryptophan in relation to other amino acids.
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