Does eating Thanksgiving turkey really make you tired?

Congrats on finishing that Thanksgiving feast and leaving no leftovers. Okay, maybe a few, but can you even deal with them right now as you're nodding off in a turkey-induced food coma? 

It seems like every year, no matter how much coffee you drink Thanksgiving morning, you require a nap after your turkey feast. 

So what's the deal — does turkey really make you tired or is this all just a state of mind? 

"The popular notion that turkey makes you tired is likely perpetuated because of the amino acid tryptophan, found in turkey and other forms of poultry," Ayelet Schieber Goldhaber, registered dietitian at NYU Langone Medical Center explained in an email. 

Human bodies run on two types of amino acids: Those made in our bodies, called non-essential amino acids, and those that we ingest through food, called essential amino acids.  

"Tryptophan falls into the category of essential amino acid, meaning our body needs to get it through food in order to establish its presence in the blood stream," Goldhaber said. 

So why does this one amino acid, tryptophan, theoretically make us sleepy? 

"The presence of tryptophan in our bodies sets off a chain of events ultimately leading to increased serotonin uptake," Goldhaber said. Serotonin is known as the happy hormone, which can also aid with sleep. Serotonin can be released in your brain after exposure to bright light, exercise or positive social interactions. If you don't feel sleepy after those, you may not be able to blame turkey for your mid-Thanksgiving nap. 

"It's hard to say if your Thanksgiving drowsiness is related to turkey alone, or the overall experience surrounding Thanksgiving day," Goldhaber said. "If you eat a turkey sandwich on a Monday afternoon and don't feel the same level of exhaustion you do on Thanksgiving, other factors are likely at play." She attributes the long day of festivities, hectic environment and a large meal as the "substantial causes of those Thanksgiving day yawns."  

Turkey is not the only source of tryptophan

Other experts agree. "Turkey doesn't make you more tired than any other foods," registered dietitian Sylvia Melendez-Klinger, said in an email. "The reason you may be tired after your Thanksgiving dinner has more to do with overeating." 

She also noted that tryptophan is found in several other foods, including poultry you more regularly eat, like chicken, and "it's important to note that turkey does not contain more tryptophan than other foods." To avoid feeling sleepy after your turkey, Melendez-Klinger recommends drinking plenty of water and staying active throughout the day and after eating — go for a walk just when the dishes are ready to be washed... 

Quit blaming your turkey drumstick feast for your desperate need for a pillow and get some fresh air.