Turkey, stuffing, mashed potatoes, gravy…Thanksgiving is a feast for the senses, but often followed by an overwhelming urge to nap. This post-dinner drowsiness is commonly known as a Food Coma. But what exactly causes this phenomenon, and is turkey really to blame?
The traditional Thanksgiving meal is often laden with carbohydrates, fats, and tryptophan-rich foods like turkey. While tryptophan, an amino acid, is often cited as the culprit for post-Thanksgiving drowsiness, the truth is more complex.
alt text: A table laden with a traditional Thanksgiving feast, complete with turkey, stuffing, and various side dishes.
Turkey does contain tryptophan, which the body uses to produce serotonin, a neurotransmitter associated with relaxation and sleep. However, the amount of tryptophan in a typical serving of turkey is not enough to induce significant drowsiness on its own. Other foods, such as chicken, beef, and cheese, contain comparable amounts of tryptophan.
The real culprit behind the food coma is likely the sheer volume and composition of the Thanksgiving meal. Large quantities of carbohydrates, in particular, trigger the release of insulin, a hormone that helps regulate blood sugar levels. Insulin also facilitates the absorption of other amino acids into muscle tissue, leaving tryptophan more readily available to cross the blood-brain barrier and increase serotonin production.
In addition to the carbohydrate load, the high fat content of many Thanksgiving dishes also contributes to post-meal fatigue. Fat slows down digestion, requiring the body to expend more energy on breaking down the food. This process diverts blood flow away from other organs, including the brain, leading to feelings of sluggishness.
The medical term for this post-meal drowsiness is postprandial somnolence. “Postprandial” refers to the period after a meal, while “somnolence” denotes sleepiness or drowsiness. So, while “food coma” is a more colloquial term, it accurately describes the feeling of overwhelming fatigue that often follows a large meal. This feeling is not unique to Thanksgiving, and can occur after any large, carbohydrate-rich meal.
The term “food coma” itself is a relatively recent addition to the lexicon, dating back to the 1980s. The word “coma” originates from the Greek word for “deep sleep.” While a food coma doesn’t literally induce a comatose state, the profound feeling of sleepiness it causes is often described as feeling like a “deep sleep.” Symptoms of a food coma include overwhelming sleepiness, a feeling of fullness, and often, regret for overindulging.