Turkey has often been attributed to the ever-so-common Thanksgiving Day nap because of its L-Tryptophan content. Tryptophan is an essential amino acid, meaning we need to eat it because our bodies cannot produce it. It is a contributor to everything from the backbone of DNA to the production of Vitamin B3. In this case, when tryptophan aids in the body’s production of Vitamin B3 (Niacin), it is also assisting the body with production of serotonin, a commonly-known brain chemical given kudos for its role in sleep.
Theoretically, eating more turkey – along with its tryptophan content – should spur production of Niacin and thus, more serotonin for a good night’s rest, right? Not quite. Tryptophan has been documented to cause drowsiness when taken on an empty stomach in the absence of all other amino acids; turkey, being a great lean protein source, has a myriad of amino acids in addition to tryptophan.
So what is making you yawn at the Thanksgiving dinner table? Perhaps it’s the story your mother is telling for the 27th time about that time when you were a kid? No? A more likely explanation is the redirection of blood to the digestive tract after meal consumption. This takes place after all meals to some extent, but will occur to more intensely after a meal with a high fat content; this is caused by the caloric content of fat. Fat requires approximately 9 calories/gram of energy to break down, which is slightly more than twice the 4 calories/gram required to break down carbohydrates or proteins. The redirection of blood to the digestive tract will divert it from other organs and the nervous system, attributing to that post-meal drowsiness.
Go ahead and curl up on the couch after Thanksgiving dinner if you’d like, but don’t forget to stop in and get your workout in before then!