If you’re planning your Thanksgiving menu, you might be spending more time plotting how you can best camouflage your veggies so your dad will eat them without calling you a “health nut” than you are thinking about the meal’s main attraction. The turkey, however, is the most storied part of the Thanksgiving feast. It’s so iconic and ubiquitous this time of year that one of its key, sciencey-sounding nutrients has even become famous: the mysterious and misunderstood tryptophan.

Upon hearing that word, you may immediately picture your uncle passed out in front of the TV after binge-eating second and third helpings from the Thanksgiving buffet. Tryptophan, after all, makes you sleepy. Right?

Sort of. According to nutritionist Keri Glassman, RD, the relationship between tryptophan and sleep is not exactly 1:1. “Tryptophan is an amino acid that increases serotonin levels in the body,” she says. “Serotonin is a precursor to melatonin, a hormone that helps regulate sleep.” In other words, tryptophan could help your body to produce more of this sleepy hormone, but how much do you need to consume for this effect to kick in?

“Tryptophan is an amino acid that increases serotonin levels in the body. Serotonin is a precursor to melatonin, a hormone that helps regulate sleep.”

“Science has shown that L-tryptophan in doses of 1 g or more produces an increase in rated subjective sleepiness and a decrease in the amount of time it takes you to get to sleep,” explains Glassman. A single gram sounds small, but getting that much tryptophan into your system may be more difficult than you think: “You’d have to consume 12 ounces of turkey—four to six servings—to equal a full gram of tryptophan,” she says. And while some may be able to pack away that much bird in one go, it’s doubtful you actually will. (You’ve got to leave room for the Brussels sprouts and sweet potatoes, after all.)

On a non-Thanksgiving note, if you suffer from sleep issues generally, it can’t hurt to increase the amount of tryptophan you’re consuming in the evening hours on a regular basis. Luckily, you don’t need to roast a turkey nightly to make this happen, as the amino acid is also found in other types of poultry, fish, yogurt, kale, bananas, whole grains, honey, nuts, eggs, and white rice. Still, even with a meal that combines a number of these foods, it’s a tough task to consume 1 full gram of it. But simply increasing your tryptophan intake may help you relax (again, thanks to the serotonin boost) and circuitously enable sleep. Plus, on a normal night you won’t have to block out your uncle’s snoring to indulge in a good snooze, which is definitely something to be thankful for.  

Tryptophan isn’t the only way to catch a good night’s sleep; here, the all-natural sleep aid you don’t yet know about, but should. Plus, find out why science says sleep meds actually sabotage your quest for quality zzz’s.