Thanksgiving often involves eating a big meal centered around turkey and then retiring to the easy chair or couch for a nap. Turkey contains tryptophan, an amino acid that is a chemical precursor to melatonin, a neurotransmitter known to induce sleepiness. However, while the holidays can be exhausting, scientists say it’s a misbelief to blame turkey for the post-meal nap.
Research has shown that, following a large meal, less tryptophan will reach the brain than on an empty stomach. The real culprit is the types and quantity of food you’ve eaten. Blame your sleepiness instead on high-calorie, high glycemic index foods.
Here are a few easy science-based tips to ensure not only a delicious turkey but a healthy Thanksgiving.
to write three letters of gratitude to people who had positively impacted their lives. The letters had to be nontrivial, insightful and reflective, and contain a high level of appreciation or gratitude expressed in a positive manner. Instead of writing letters, a control group filled out questionnaires. 
