Talking turkey: Does tryptophan make you tired on Thanksgiving?

You're getting sleepy: Is it the tryptophan in the turkey that makes you tired on Thanksgiving or other ingredients of your big feast?
You're getting sleepy: Is it the tryptophan in the turkey that makes you tired on Thanksgiving or other ingredients of your big feast?Courtesy LonelyBob
I’ve got some friends who are already pushing the Thanksgiving envelope and having some early holiday dinners this weekend. Most of us will wait until Nov. 22 to gorge out on a big meal of turkey, and then feel quite tired and bloated from the experience.

And all of us scientific-minded people like to sound very sciency at those moments and talk about the effects that tryptophan in the turkey are having on our bodies. I’ve bought into that thinking for decades and thought I’d Google around the net to learn more about that, and was surprised to see that I’ve probably been duped.

Turkey does in fact contain high levels of tryptophan, but not anything significantly higher than lots of other meats. Tryptophan is an amino acid that our bodies can’t produce. And taken on an empty stomach, it can have a soothing, calming effect. It was even marketing as an anti-insomnia drug in the 1980s until some other significant side effects – muscle pain and death – led the government to ban it as a medication.

After a big feast, out stomachs are dealing with the amino acids from many different food sources, meaning that the tryptophan has a lot of competition in our body chemistry.

Here’s what’s more likely going on in our bodies to make us tired: the impacts of having lots of other carbohydrates in our stomachs. Carbo-heavy items like mashed potatoes, stuffing and pie take our bodies a lot of effort to digest. That internal work is a lot to handle and our bodies tire out.

So that’s the nutritional answer to why Thanksgiving dinners make us tired. I think you might also be able to chalk up your tiredness to the quality of conversation with the relatives you’re sharing the meal with or the fact that the Detroit Lions are always playing football that afternoon.

How do you deal with post-Thanksgiving dinner lethargy? Share your thoughts here with other Science Buzz readers.

Your Comments, Thoughts, Questions, Ideas

hannah  banana's picture
hannah banana says:

turkey makes me tired and sleepy. end of story.

posted on Fri, 11/16/2007 - 11:32am
Anonymous's picture
Anonymous says:

who gets tried of food like really

posted on Fri, 11/16/2007 - 8:06pm
Shooman's picture
Shooman says:

Hannah Banana, I wholeheartedly agree. Turkey definitely makes me sleepy. Today, when i publicly announced such, I got laughed at. I hate turkey, it made me get laughed at. I heart pork.

posted on Tue, 11/20/2007 - 8:45am
Chuck's picture
Chuck says:

Sounds like the turkey industry has done a good job funding studies and spinning the results! Tryptophan (and turkey) had a tough time in the 1980's when supplements had some ill effects on people and some very bad press. The bottom line is, unlike any other food that I eat, I get tired (and a headache) from eating turkey. Period. It doesn't have to be with a Thanksgiving dinner. This happened long before I ever heard of tryptophan. Turkey has a much higher amount of tryptophan than most other foods (ie: eggs, etc.) Take 20 'researchers' and give them a 'turkey test'. After they wake up from their sleepfest, let them go back to their labs and re-examine their data. Gobble gobble!

posted on Thu, 11/22/2007 - 10:05am
Joe's picture
Joe says:

Yeah, it's not tryptophan that makes you sleepy, its serotonin. Tryptophan is an amino acid that helps the body produce niacin, a B-Vitamin, which helps produce serotonin, which makes you sleepy. Turkey does not have as much tryptophan as other foods such as beef or soy beans. Tryptophan is also found in chocolate, bananas, milk, peanuts and fish.

And the Motor City Kitties have at least a decent offense, it's those darn Cowboys I dislike watching.

posted on Thu, 11/22/2007 - 9:08pm
Anonymous's picture
Anonymous says:


posted on Sun, 11/25/2007 - 9:59pm
Anonymous's picture
Anonymous says:

You people are forgetting about insulin. When you eat too much or too many simple carbohydrates you body produces excess insulin to deal with the food overload. Insulin is a hormone which can make you sluggish. If your into playing sports you would not eat a big meal or sugary foods two hours prior to game time or you would not be as competitive. There are many sports articles and books dedicated to this.

posted on Tue, 11/27/2007 - 8:34pm
Randy's picture
Randy says:

I am 50 years old, and turkey has always made me sleepy, even when eaten by itself and in small amounts. Turkey's drowsiness effect for me is unlike any other food I can think of, and I don't drink alcohol or use drugs. Based on this, I am disappointed in the unprofessional way in which so many articles have been written and in their unscientific generalizations.

posted on Wed, 11/28/2007 - 1:50am
GM's picture
GM says:

I don't know about the science of it all but turkey makes me sleepier than any other food I know of, or for that matter several glasses of wine.
I rarely eat turkey now because it makes me so tired. I used to buy turkey sandwiches for lunch at work but was so desperately tired after eating them that I had to go sleep in my car, which became embarrassing.
The only thing comparable to turkey, for sleep inducing properties for me, was Fenergan, the antihistamine, which I used as a sleeping pill on flights.
If turkey doesn't affect some people, so be it. But it's effect is amazing for me.

posted on Fri, 11/20/2009 - 7:56am
Anonymous's picture
Anonymous says:

It concerns me that your article and at least one of the comments refers to tryptophan causing muscle pain and death. I have read in several sources that in the 1980's, a Japanese supplier sent a contaminated batch of tryptophan to the US which caused those problems. One article I read said he later admitted he knew it was bad stuff before he sent it. I don't think it is accurate the way you are saying those things were caused simply by tryptophan. It is used widely in Europe as a safe anti-depressant, unlike all the SSRI's we are using here that do indeed cause suicidal tendencies in people. SSRI's don't allow the reuptake of serotonin in the brain, which can lead to serious depletion of other key mood balancers in the brain. Tryptophan is a much safer alternative. And for the thousands of people who have trouble sleeping due to depression, that is a very nice side benefit.

posted on Fri, 09/10/2010 - 9:25am
Anonymous's picture
Anonymous says:

For some odd reason, turkey does not make me tired. I have no idea why.

posted on Sat, 11/27/2010 - 9:18am

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