ZocdocAnswersWhat causes one to always be tired after lunch?

Question

What causes one to always be tired after lunch?

I find that after every lunch, I do have a period during which I'm very sleepy. When I was younger, I wrote this off as just normal, but now I'm starting to wonder if it has to do with the big blood sugar spike from the meal. Is that possible? If so, is the spike hard on my body in other ways?

Answer

Feeling tired after eating lunch is a very common physiologic response experienced by most people. Fortunately, it rarely indicates a serious problem and can be usually managed by changing what you eat at lunch. The doctors who will be qualified to discuss this with you include your family medicine doctor or your internal medicine doctor. Feeling tired after lunch is caused by two changes in the body related to digestion. The first is that rising insulin in the blood, which is important to manage the sugar you have ingested at lunch, causes drowsiness at the level of the brain. The second is that the parasympathetic nervous system, which is important for digestion, diverts blood to your intestines after a meal, making you less alert. To deal with these effects, it is helpful to eat smaller meals at lunch and meals higher in protein and lower in processed foods and carbohydrates. It will also be helpful to avoid alcoholic or sugary beverages. Finally, it can be helpful to perform some exercise after lunch, such as a brisk walk, to counter the effects of the parasympathetic nervous system. As always, the diagnosis and management of your specific condition will require a physical examination by your personal physician. Scheduling an office visit with your primary care doctor may be indicated.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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