With Thanksgiving approaching, my mind often thinks of all the mouthwatering food I soon will consume. If you are like me, you probably find yourself stuffed and tired after dinner. Turkey often gets the blame for why you start to become drowsy, but why do we blame the turkey? You may have heard that turkey contains high tryptophan levels, an amino acid that’s often linked with sleep. To better understand how tryptophan affects the body, let’s digest some food chemistry.
Tryptophan and other essential amino acids come from all the protein in our diet. These amino acids swim through the bloodstream, nourishing our cells. Brain cells convert tryptophan into a chemical called serotonin. This neurotransmitter helps regulate sleep and appetite. Having high serotonin levels can result in being calm and relaxed. But consuming tryptophan isn’t enough to cause serotonin production, and this amino acid by itself isn’t enough to make you sleepy. In fact, turkey contains not just tryptophan but a whole lot of protein and other amino acids that compete with tryptophan to enter the brain, keeping you awake instead of putting you to sleep.
So why am I sleepy? While turkey does contain tryptophan, it’s not the only food that includes many of these amino acids. Almost every high protein food like meats, cheese, and nuts, contains tryptophan. Turkey actually has the same amount of tryptophan as chicken, pork, or beef.
So if the turkey is not the culprit, who’s to blame? It may actually have to do with the side dishes. Mashed potatoes, stuffing, bread, and desserts contain many carbohydrates that stimulate the release of the hormone insulin. Insulin encourages our muscles to absorb certain amino acids from the blood, but not tryptophan. So eating all those carb-heavy side dishes increases the amount of tryptophan in the blood relative to other amino acids. This means that more tryptophan gets into the brain because there are fewer amino acids to compete with!
If you are feeling tired after Thanksgiving don’t blame the carbs just yet. While carbohydrates help to transport tryptophan through the blood-brain barrier, the main reason we find ourselves tired could simply be the case of overindulging. After all, Thanksgiving only comes once a year! All the food you eat, whether that includes turkey or not, needs to be digested. While your body works hard to break down the food we eat, the best way for your body to conserve energy is by resting on the couch after a great turkey day.
Happy Thanksgiving from our family at the Connecticut Science Center to yours.
This content was made possible in part by the Institute of Museum and Library Services.
Justin Riley is the Teen Programs Coordinator and STEM Educator at the Connecticut Science Center, where he works closely with high school students giving them access to STEM and leadership programming. Justin graduated from the University of Hartford with his Bachelors in Electrical Engineering Technology and a Masters degree in Counselor Education and Student Development. Justin has worked several years with a wide range of students from pre-k to college. His love of engineering and mentoring led him to the Connecticut Science Center where he gets to use his many talents to work and connect with the students in the Greater Hartford area. When he is not helping to run the teen program, he spends his time traveling and spending close time with family and friends.