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:
Fats slow down the digestive system, giving Thanksgiving dinner plenty of time to take effect. Fats also take a lot of energy to digest, so the body will redirect blood to your digestive system to tackle the job. Since you have less bloodflow elsewhere, you will feel less energetic after eating a meal rich in fats.
Other Causes. Food allergies sometimes cause headaches and fatigue after eating. For example, people with milk allergies might develop a headache after eating yogurt, butter, cream or cheese. The body releases the chemical histamine during an allergic reaction, which causes sinus cavity swelling. This inflammation leads to headaches.