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Myth: Turkey Makes You Sleepy On Thanksgiving

You've just finished a huge Thanksgiving meal and being to doze off. You think, "Wow, it's the turkey that's making me tired."

One of the most common Thanksgiving myths is that turkey, which contains the natural chemical tryptophan, makes you sleepy. But the feeling of drowsiness is probably more correlated to drinking alcohol, bad and awkward conversation and a carb-heavy meal.

What Is Tryptophan?

Tryptophan is an amino acid that is essential for good bodily health. The human body uses tryptophan to build certain proteins. You may be thinking, "Wait, it must be associated with sleep!" You're correct. The body uses tryptophan to make the neurotransmitter, serotonin, which helps the brain regulate sleep.

While turkey does contain tryptophan, other meats contain comparable levels as well. Cheddar cheese, for example, contains more tryptophan gram for gram than turkey. However, you never eat cheddar cheese and blame it for increased drowsiness.


So, why do we get so tired on Thanksgiving?

Well, simply put, it's because we eat a lot of carbohydrates. Vegetables, stuffing, bread, pie, and mashed potatoes are loaded with carbohydrates. This massive intake of carb-heavy calories stimulates the release of insulin. This release triggers amino acids out of the bloodstream.

Since the amino acids are out of the bloodstream, tryptophan can make its way to the brain to produce more serotonin. Minus a surge in insulin, tryptophan would compete with other amino acids in the meal as they make their way to the brain. In this scenario, not enough tryptophan would reach the brain because the other amino acids are more abundant in the food.

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