There are the following reasons for being sleepy at 10 am every day: 1. Eating too much at breakfast or eating a lot of high-calorie food can cause sleepiness around 10 pm every day, it is recommended to avoid over-eating in the morning and avoid being too full. 2. Sleepiness at 10 am every day may also be a symptom of people who are recovering from a serious illness or are extremely weak, it is usually not recommended to exercise vigorously, only suitable for walking, jogging and other soft exercises. 3, sleepy at 10 am every day may also be caused by sleeping too late the night before or poor sleep quality, it is recommended that patients usually adjust their sleep habits and avoid staying up late.