Does eating turkey meat cause sleepiness?

Answer 1

Does Tryptophan from turkey meat make you sleepy?
Right around Thanksgiving, it is quite usual to find articles like this one and this one that claim that eating turkey will not make you sleepy because tryptophan will be digested, that tryptophane levels in the brain will decrease in concentration due to amino-acid competition, or that eating turkey may even boost your mood through the rise in serotonin, though the dose may be too low.

What these authors do not know is that a number of papers have been published suggesting a different mechanism altogether, not dependent on tryptophan (or serotonin) getting released into the bloodstream and reaching the brain at all. Let's first review the biosynthetic pathway of melatonin. Here it is in a simplified shorthand:

The amino-acid tryptophan is a precursor of neurotransmitter serotonin which in turn is the precursor of hormone melatonin.

Not everyone knows that the complete enzymatic machinery for synthesis of melatonin is not active only in the pineal organ. It is also fully functional in the retina of the eye, in the Harderian gland (located in the ocular orbit just behind the eyeball), and in the intestine. After all, the GI tract possesses a large and complex semi-independent nervous system in which many of the same neurotransmitters and hormones are found as in the brain. Actually, more melatonin is produced in the intestine than in all the other sites combined.

Normally, intestinal melatonin plays a role in control of gut motility - peristalsis - and perhaps some other local functions. As usual, effects of serotonin and melatonin are opposite: whatever one stimulates, the other tends to inhibit.

In most species intestinal melatonin gets degraded within the intestine. In other words, little or no melatonin ever leaves the intestine and leaks into the bloodstream. Also, depending on the species, melatonin in the intestine is predominantly synthetized during the day, during the night, or continuously. In humans, it appears that some intestinal melatonin (not much, though) leaks into the blood at all times, and that most of the synthesis happens during the day.

The ability of the intestine to synthetize melatonin out of food tryptophan (described above) is the first link in the chain of our hypothesized mechanism.

The second link is, and that has been shown in rats and chickens, ability of extra tryptophan to promote synthesis of extra melatonin.

The third link, also demonstrated in rats and chickens, is that extra melatonin leaks from the intestine into the bloodstream even if it normally does not do so in that particular species.

The fourth link, also demonstrated experimentally, shows that melatonin secreted from the intestine does not in any way affect the levels of melatonin synthesis in other locations (pineal, eye).

Finally, it has long been known that increasing levels of melatonin in the bloodstream can phase-shift the circadian clock, place the phase into the night, and thus promote the feeling of sleepiness.

Now, as far as I know, nobody has done the complete study - all links in the chain - in any species, let alone humans. Still, as each link has been independently verified in one species or another, the whole hypothetical mechanism appears likely. Thus, until further research proves this wrong, you can tell your friends at dinner table this:

High levels of tryptophan in turkey meat and some other foods lead to increase in synthesis of melatonin in the intestine which results in more melatonin leaking from the GI tract into the bloodstream. Once in the blood, this extra melatonin phase-shifts the clock - your body thinks it is late at night and you feel sleepy as a consequence.

Furthermore, this shift of the clock will result in you being wide awake right after midnight - your body thinks it's waking-up time already - something that has been reported anecdotally.

Answer 2

We'd always heard that post-turkey lethargy was a result of a natural chemical found in turkey, the same one that makes a glass of warm milk such a touted sleep aid.
We were surprised when we found a page of turkey tidbits at the University of Illinois Extension site that asserted, "Eating turkey does not cause you to feel sleepy after your Thanksgiving dinner. Carbohydrates in your Thanksgiving dinner are the likely cause of your sleepiness."

Not willing to write this off as a culinary urban myth, we moved on. Dr. Weil, a popular health guru, seemed to confirm our long-held belief, at least intially. He affirmed that the amino acid L-tryptophan found in turkey skin is a natural sedative. But, the good doctor points out that this probably isn't the cause of post-turkey sleepiness:

L-tryptophan doesn't act on the brain unless you take it on an empty stomach with no protein present. So I don't think the amino acid is to blame for the sudden lethargy that hits just about when it's time to do dishes. That's more likely due to drinking alcohol and overeating...
So, this Thanksgiving, moderate your alcohol and side-dish intake rather than passing on seconds of the bird. Have a happy holiday!

Answer 3

well turkey meat can cause you to become sleepy. I remember once when I worked a double shift an all nighter and came home for dinner after I ate I laid down and fell asleep. I did not have turkey though. hmmm infact I fell asleep while eating.so I guess just looking at turkey can make you tired.

Answer 4

I read something about eating lots of meat making u sleepy yes

Answer 5

Yes turkey meat makes you sleepy so does tuna.

Answer 6

It's the combination of turkey and potatoes. Something about an enzyme that when you eat the both of them at the same time, you get sleepy.

Answer 7

after eating any big meal, the blood rushesd to your stomach to help with the digestion and we do feel sleepy. Maybe you've heard turkey because we tend to over eat at Holiday time.

Answer 8

Yes

Answer 9

Turkey contains tryptophan which does cause sleepiness.

Answer 10

They say that it does. On Thanksgiving, after I've had my meal. I get very sleepy. Sometimes I even take a little nap.