Postprandial sleepiness is the feeling of drowsiness or fatigue that often occurs after eating a meal. This is a common phenomenon that can affect people of all ages and is usually temporary. It is believed to be caused by a combination of factors, including the body’s natural circadian rhythms, the release of hormones such as insulin and serotonin, and the relaxing effect of food on the body. Some people may be more susceptible to postprandial sleepiness than others, and certain foods or meals may be more likely to trigger the feeling.