This is the type of vitamin D that circulates in the blood. Itâs considered a good reflection of how much vitamin D youâve absorbed from sun exposure and taken in from foods. Levels of vitamin D are expressed in nanomoles/liter (nmol/L) or nanograms/milliliter (ng/mL). According to the Office of Dietary Supplements (ODS), the results can indicate the following:
Other Health Conditions. On rare occasions, being tired after a meal or simply sleepy all the time could be a sign of another health problem. Diabetes, anemia, underactive thyroid, celiac disease, food intolerance, and sleep apnea can make post-meal drowsiness worse.
View full size image. Contrary to popular belief, eating turkey isn't the main reason you feel sleepy after a Thanksgiving feast. The oft-repeated turkey myth stems from the fact that turkey contains the amino acid tryptophan, which forms the basis of brain chemicals that make people tired.But turkey isn't any more sleep-inducing than other foods.ut tryptophan competes with all of the body's other amino acids to enter the brain, through a strict gatekeeper known as the blood-brain barrier. It's the heaps of carbohydrates â the stuffing, potatoes and yams smothered in marshmallows â that are the true problem, according to medical experts.