Tired after eating? Here’s why, and how to fix it

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After a busy morning, lunch can feel like just the pick-me-up you need — but sometimes the meal you thought would energize you is the very thing that makes you want to nap at your desk.

“As a registered dietitian (nutritionist), I’ve heard people say that often over my career, so I think it’s fairly common for people to have that response,” said Julie Stefanski, a spokesperson for the Academy of Nutrition and Dietetics.

Feeling tired after lunch, or post meals in general, is known as postprandial somnolence — or, colloquially, the food coma.

Part of this phenomenon is due to basic physiology: When humans eat, most of our blood goes to the digestive organs to process the food, said Sandra Arévalo, director of community health and wellness at Montefiore Nyack Hospital in New York state and national spokesperson for the Academy of Nutrition and Dietetics.

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After a person eats, the body might produce more serotonin, a neurotransmitter that regulates sleep and mood — especially if the food was high in the essential amino acid tryptophan, which is found in proteins such as chicken, cheese and fish, according to the Cleveland Clinic.

The tendency to get tired after eating isn’t inherently suggestive of something amiss. However, you might think of it as a problem due to cultural norms, particularly in the United States, that “fight against our natural processes” by mandating productivity instead of rest when the body needs it, Stefanski said. “I always think about Spain and people that have told me when they visited places where they do take a siesta,” she added.

But there can be additional factors that exacerbate this natural response, making getting through the rest of the workday or any activities feel like a slog. Here’s what to watch out for and how to make adjustments.

When it comes to why you feel overly tired after eating, a common cause is consuming meals that are heavy in terms of quantity or quality.

Some people overeat instead of stopping when they feel comfortably satiated, especially if they’re distracted by multitasking. Not eating breakfast can also lead to overindulging later in the day if excessive hunger makes controlling your appetite difficult, Arévalo said.

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“Someone that feels very tired after a meal might consider looking at slowing down their eating and cutting back on their portions a little bit to the point that they’re not overeating,” Stefanski said. “Because no matter what you eat — whether it’s carbs, fat, protein — if you eat a lot more than what your body is designed to handle, your body’s going to spend a long time digesting that food.”

If you can’t always step away from whatever you’re doing to be present with your meal, taking even just five minutes to do so can help, experts said.

Sometimes, however, the makeup of certain foods can contribute to tiredness. Fats are the hardest nutrient to digest because their molecules are much larger than those of protein or carbs, Stefanski and Arévalo said. If you had a meal high in fat — such as fried foods or pizza — that could make you feel tired. Meals high in added sugar or refined or highly processed carbohydrates can have the same effect because of how the body metabolizes these items versus sugar or carbs in natural or minimally processed foods.

The fiber in so-called whole foods slows the absorption of sugar into the body, which means they don’t cause blood sugar or insulin spikes and instead give you more stable, lasting energy, said Kristin Kirkpatrick, a registered dietitian at the Cleveland Clinic.

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If your lunch mostly consists of carbs and then dessert on top of that, your blood sugar and insulin levels can rapidly increase.

Then, “a lot of times your blood sugar drops below where you originally started from,” Kirkpatrick said. “That can really be an energy zapper.”

Just like high-sugar foods, sugary drinks can also make you feel tired once the crash hits, Stefanski said. Additionally, alcohol is a sedative, so if you’re commonly having alcoholic beverages with lunch, abstaining is one of the first places to start, she added.

Choosing more balanced meals and snacks can help you feel less tired after eating, experts said. That could look like a bean-based soup and a salad with an olive oil-balsamic vinegar dressing; lean proteins such as salmon, white chicken meat or beans; and other toppings that aren’t high in sugar, Kirkpatrick said. A whole-grain wrap with white turkey meat, cheese and vegetables is another option. And if you’re in a pinch, try having an apple with nut butter instead of grabbing a candy bar. Packing your own food can help you refrain from grazing on vending machine snacks, fast food or free office doughnuts.

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“A five-minute walk or something helps to improve circulation and alertness, as well,” Arévalo said.

Sleep regulates your hormones, including your digestive ones, according to Kirkpatrick. And if you’re sleep-deprived, your body’s likely to suppress the hormone called leptin that signals “I’m full and don’t need any more” or elevate ghrelin, the hormone that commands “feed me,” she explained. Being insufficiently rested can also negatively affect your decision-making skills, emotional regulation and a brain region that regulates food intake, making it harder to resist cravings for highly palatable foods.

You can improve your sleep by making sure you sleep for seven to nine hours per night in an environment that’s cool, dark and quiet. Avoid drinking caffeine at least six hours before your usual bedtime or drinking alcohol before bed. Having a wind-down routine and reserving your bedroom for sleep and sex only can also help.

For some people, post-meal fatigue can signal something more serious.

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“Statistics show right now that a lot of people in the US have diabetes or prediabetes and don’t know it,” Stefanski said. When someone can’t properly metabolize carbs and therefore has a high amount of insulin in the blood, that can diminish energy levels, she added.

If you regularly feel drowsy after eating even after making dietary adjustments, ask your doctor to administer the hemoglobin A1c test. The test measures average blood sugar levels and shows how much glucose is attached to hemoglobin in red blood cells, Stefanski said.

“If that’s high,” she said, “it shows that your body is struggling to metabolize food and metabolize carbohydrates.”