Postprandial somnolence, commonly referred to as the food coma, is the feeling of fatigue that occurs after lunch or meals in general.

Physiologically, this phenomenon occurs: As a result of eating, most blood goes to our digestive system to process food, according to a statement made by Sandra Arévalo to CNN. She is the director of community health and wellness at Montefiore Nyack Hospital and the national spokesperson for the Academy of Nutrition and Dietetics [1].

The body may produce more serotonin after eating, per the Cleveland Clinic. This neurotransmitter regulates sleep and mood in foods high in tryptophan, such as chicken, cheese and fish [2]. Getting tired after eating doesn’t necessarily mean something needs to be fixed.

However, it may be an issue due to cultural norms, particularly in the US. Other countries do take siestas [3].

Energy-depleting habits

You might be surprised by the worst habit for energy levels. BetterNowMD‘s Dr Mary Valvano says it’s eating your biggest meal at the end of the day [4].

Food is metabolized differently by our cells depending on the time of day. Our body’s ability to use the same meal at 8 am versus 6 pm can differ. Late meals (especially late at night) can adversely affect our blood sugar levels and ability to get the most energy from the next day’s meals.

Feeling tired after a meal is a common occurrence, mainly if the meal is rich in carbohydrates and protein. Digesting a meal takes around 30 to 40 hours. The body is continuously working to break down food, and when you eat more can slow down the digestive system, especially with heavier meals.

Hormones also play a significant role in digestion. Some researchers suggest that increased serotonin production after eating may contribute to tiredness [5].

Aside from that habit, here are some more things to consider:

Issues with blood sugar

If you feel drowsy after eating despite making dietary adjustments, ask your doctor to administer a hemoglobin A1c test. In the test, glucose levels are measured in the blood and the amount of glucose attached to hemoglobin in red blood cells is determined.

Sugary or heavy meals

The quantity or quality of your meal may cause you to feel overtired after eating heavy meals. It is common for people to overeat rather than stop when they feel satisfied, especially if they are distracted by multitasking. If excessive hunger makes controlling your appetite difficult, skipping breakfast can also lead to overindulging later in the day.

Sleep deprivation

If you’re sleep-deprived, your body will likely suppress the hormone leptin, which signals “I’m full and don’t need any more,” or elevate ghrelin, which signals “feed me”. Also, sleep deprivation affects your ability to make decisions, regulate your emotions and control your food intake, so you will find it more difficult to resist cravings for highly palatable foods.

Getting in touch with your doctor when necessary

According to Harvard Health, fatigue lasting longer than a week or two can usually be fixed with a few simple changes [4]. Various health conditions, such as infections, hypothyroidism, hyperthyroidism and sleep disorders, can contribute to low energy levels.

Energy levels can also be affected by inactivity, poor nutrition and stress. A doctor may be able to help you if you experience chronic fatigue.

[1] https://www.montefiore.org/nutrition-experts
[2] https://health.clevelandclinic.org/tired-after-eating/
[3] https://www.sleepfoundation.org/circadian-rhythm/siestas
[4] https://www.health.harvard.edu/staying-healthy/when-should-you-worry-about-fatigue
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6888666/