People are always talking about how turkey comas or post-Thanksgiving meal naps, and only recently did I hear that it was somewhat common knowledge that it’s the turkey that specifically makes you tired. I had always assumed it was just due to the sheer amount of food you’re consuming at Thanksgiving dinner that made you sleepy later that evening. So, of course, I questioned this idea that turkey is actually making us tired. If turkey has something weird in it that’s affecting our level of sleepiness, why would we continue to eat it?
This can’t be a situation of reverse causation- the time frame rules out that your tiredness could cause you to eat more turkey, since you’re getting tired after you eat the turkey. There’s also always the possibility of chance. And of course, maybe I should be listening to everyone else talking about this turkey tiredness because they could all be correct, but I went into the research for this blog post with a sneaking suspicion that it was due to a third confounding variable. So, let me tell you what I now know, and what you should pass on to your uncle who won’t stop making excuses for why he has to nap on your couch after dinner.
The reason people have it in their minds that turkey has us all napping after Thanksgiving dinner is that turkey has an amino acid in it called tryptophan. Within the body, tryptophan is used to make the neurotransmitter serotonin, which has connections to our sleep. If this amino acid was by itself in our foods, it could make us more tired, but, it’s never on its own and therefore is not going to increase your serotonin. There’s this idea that turkey has more tryptophan in it than other foods that you eat on more of a daily basis, but that isn’t true. In fact, some nuts and cheeses are filled with more tryptophan than turkey. All poultry has this amino acid at just about the same amount as turkey and, according to a professor from Texas A&M University, you can find tryptophan in pretty much every protein.
So if turkey isn’t making us tired, why do so many people feel the need to nap after dinner? LiveScience mentions that some experts in this field say that it’s more likely because of the amount of carbohydrates you’re eating and alcohol you’re drinking. Maybe next year at Thanksgiving, consider going easy on the cheese plate, mashed potatoes, and champagne if you don’t want to sleep after your meal, and stop blaming turkey and tryptophan for how carbs and alcohol are making you feel!