We’ve all felt it — that drowsy feeling that sneaks in after a meal. You’re full and relaxed, and you’re struggling to keep your eyes open. Why are meals so often followed by a sudden urge to take a nap, and should you be concerned about it?

In general, a little bit of sleepiness after eating is completely normal and nothing to worry about. There are several factors that contribute to this post-meal phenomenon, and there are a few things you might be able to do to minimize those drowsy effects.

Your Digestion Cycle

Your Digestion Cycle

Your body needs energy to function — not just run after your dog or put in time at the gym — but to breathe and simply exist. We get this energy from our food, which is broken down into fuel, or glucose, by our digestive system, and then macronutrients provide calories, or energy, to our bodies. More than just changing food into energy, our digestive cycle triggers all kinds of responses within our body.

Hormones such as cholecystokinin (CCK), glucagon, and amylin are released to increase satiety, blood sugar rises, and insulin is produced to allow this sugar to go from the blood and into the cells, where it is used for energy. Interestingly, there are also hormones that can increase in the brain, such as serotonin, that can lead to drowsiness. Melatonin, the other hormone that induces sleep, is not released due to eating, but food does influence melatonin production.

Your Diet

Your Diet

Though all foods are digested in much the same manner, not all foods affect your body in the same way. Some foods, like turkey, can make you sleepier than others. Turkey and other high-protein foods, along with spinach, soy, eggs, cheese, tofu, and fish contain the amino acid tryptophan, which is used by the body to create serotonin, possibly responsible for that post-meal haze. Cherries affect melatonin levels, carbohydrates cause a spike and subsequent fall in blood sugar, and the minerals in bananas relax your muscles. Any one of these factors could leave you sleepy.

The good news is, there are foods that can have the opposite effect. For instance, a balanced diet that includes vegetables, whole grains, and healthy fats promotes sustained energy. Drinking plenty of water, avoiding too much sugar and eating smaller, more frequent meals can also help.

Your Sleeping Habits

Your Sleeping Habits

It’s no surprise that not getting enough quality sleep can affect how you feel after a meal, too. If you’re relaxed and full, your body may feel more like resting, especially if you didn’t get enough sleep the night before.

The Mayo Clinic suggests sticking to a regular sleep schedule, limiting stress, and including exercise as part of your daily routine to help you get a better night’s sleep. Though they also recommend avoiding midday naps if you struggle with getting a good night’s sleep, at least one study found a post-lunch nap to improve alertness and both mental and physical performance.

Your Physical Activity

Your Physical Activity

Even more than helping you sleep better at night, exercise can keep you alert during the day, minimizing the risk of your post-meal slump. Multiple studies found that regular exercise helps increase energy and reduce fatigue. In other words, being sedentary doesn’t create some sort of energy reserve that you can tap into at will. Instead, being active will help ensure that you have the energy to push through your days.

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. If you’re frequently tired and have one of these conditions, talk to your doctor about possible solutions. If you’re unaware of an underlying medical condition but have other symptoms in addition to post-meal sleepiness, your doctor may help you identify what’s causing the slump.

Feeling Tired After a Meal Is Completely Normal

If you feel tired after a meal, there’s a good chance it’s just your body responding to all of the biochemical changes caused by digestion. In other words, it’s completely normal. However, if the symptom is disruptive and/or changing your lifestyle habits doesn’t seem to help, it might not hurt to talk to your doctor.