Why Do You Get So Tired After Eating? (2024)

You just finished lunch. Not only do you feel full, but now the afternoon slump is setting in.

So, why is it that you’re always tired after eating?

Overall, it’s common to feel a dip in your energy levels after eating, but there are steps you can take to minimize the effects.

Registered dietitian Julia Zumpano, RD, LD, explains what causes it and how you can fight the fatigue.

Why do you feel so tired after eating?

Postprandial somnolence, that feeling of sleepiness after eating, can be attributed to a few different things. Some of the foods you eat can release certain hormones that may make you tired. When you eat can also contribute to feeling fatigued. And how much you eat can play a role, too.

Another factor can be your sleep quality. It’s recommended that you get seven to nine hours of sleep each night. But even if you have trouble sleeping one night, it can throw off your circadian rhythm causing your body to be out of whack all day long.

“You want to understand how much sleep your body needs,” says Zumpano. “Everyone needs different amounts of rest.”

Track the hours you sleep to help you find the magic number of hours you need to feel rested and refreshed throughout the day.

Also, be cautious with alcohol, as it can lead to feeling more sluggish after a meal, says Zumpano.

Is feeling tired normal?

It’s common to feel tired after eating a meal, especially if it’s a meal full of carbohydrates and protein.

“It takes between 30 to 40 hours to digest a meal,” says Zumpano. “Your body’s working all the time to digest food. It’s already digesting food to begin with, and then you put more food in there. And if it’s a heavy meal, it’s just going to bog down your system.”

Hormones also play an important role in your digestion.

“Some researchers believe that people feel tired after eating because their body’s producing more serotonin,” says Zumpano. “Serotonin is the chemical that regulates mood and sleep cycles.”

Tryptophan is an essential amino acid found in protein-rich foods like chicken, eggs, cheese and fish. Tryptophan helps your body produce serotonin.

“Oftentimes, when you’re eating ameal rich in carbohydrates and protein, you may feel sleepier because you have an uptake of tryptophan from the protein and then an increase of serotonin,” explains Zumpano.

Eating also causes your blood sugar levels to rise, which can lead to a decrease in energy.

“After you eat a meal, insulin is the key that unlocks sugar into your bloodstream,” says Zumpano. “After you eat a meal, your blood sugar rises. Insulin goes into the bloodstream to take the sugar out of the blood and put it in the cells for energy.”

If you don’t have enough insulin or if you have a rise in blood sugar, it can affect your fatigue level.

Does the food you eat matter?

Yes. Meals that are rich in protein and carbohydrates may make you feel more tired than other foods.

Foods that are rich in protein include:

• Chicken.
• Eggs.
• Spinach.
• Milk.
• Cheese.
• Fish.
• Soy products.

Foods that are high in carbohydrates include:

• Desserts like cakes and cookies.
• Pasta.
• White bread.
• Rice.
• Sugar and candy.

And if you’re eating larger quantities, it can overload your digestive system in addition to releasing hormones that can cause tiredness.

“Heavy meals take longer to digest,” notes Zumpano. “So, if you’re eating a heavier meal or a bigger meal, you’re more likely to feel sluggish because your body has to work a little extra hard to digest that meal.”

Zumpano says it’s best to eat a well-balanced meal that contains whole foods, protein, fiber and healthy fats.

How to recover from fatigue after eating

Tired of feeling tired after eating? Zumpano walks us through some strategies.

Eat smaller meals throughout the day

Instead of eating three big meals each day, try eating smaller meals throughout the day.

“Have half the portion of your normal meal and then add a snack before and after,” says Zumpano. “That amount of food is a lot easier to digest and you tend to have short bursts of energy from your food versus a heavier meal that may leave you feeling more lethargic.”

Snacks like a piece of fruit or a serving of nuts can help keep you satisfied between meals.

Focus on sleep

Sleep can affect how you feel after eating. Your circadian rhythm, your body’s 24-hour internal clock, affects energy levels. If you’re not sleeping enough, your circadian rhythm is off and can cause sleepiness.

So, listen to your body. Do you feel tired and like you need more sleep? Take a look at how much sleep you’re getting and if it’s working for you.

“Some people might fight through fatigue at night, and then they end up staying up late, and then they have trouble the next day,” says Zumpano. “They push through their natural circadian rhythm when they should be going to bed.”

If you start feeling tired at 9:30 p.m. or 10 p.m., Zumpano suggests trying to wind down and going to sleep earlier.

But if you’re struggling to stay alert and focus during the day, don’t overlook the power of a nap.

“If you have the opportunity to take a short nap in the day, that will help,” Zumpano says.

Exercise

By moving your body — whether that’s a short walk around the block or a quick yoga session — you’re helping stabilize your blood sugars and keep your energy levels consistent.

“If you’re going to have a big meal, I would suggest taking a 10- or 15-minute walk to get your digestion going,” says Zumpano. “Exercise can give you this natural burst of energy, too.”

Think about what you’re eating

It’s important for your meals to be balanced.

“We often focus on the carbs and protein, which are essential parts of a meal, although vegetables can commonly be overlooked,” says Zumpano. “Consume carbohydrates in the form of beans or vegetables like sweet potatoes, squash, peas or red-skinned potatoes. Fill half of your plate with non-starchy vegetables and the other half split between protein and carbohydrates.”

Zumpano suggests that you divvy up your meals using a portioned container so you can load up veggies in the biggest area and use the smaller sections for carbs and protein.

Watch your caffeine

Food comas often have us reaching for additional cups of coffee. But you want to limit how much caffeine you drink.

Too much caffeine can have the opposite effect. While it might wire you through the rest of your workday, it can impact how and when you fall asleep at night.

“Try to let that first coffee cup of coffee extend throughout the morning,” advises Zumpano. “Try to sip on it. If you want to drink multiple cups, try doing half decaf or maybe switch to black tea or caffeinated tea, so you’re not getting as much caffeine at once.”

Bright-light therapy

A study suggests that using bright-light therapy, also known as phototherapy, can help you avoid that post-eating slump.

“Having a bright-light lamp at your desk or your place of work after lunch can help,” says Zumpano.

When is fatigue serious?

If you’ve tried the above strategies and still feel fatigued after eating, it may be time to talk to your doctor.

Medical conditions that can cause excessive tiredness after eating include:

• Anemia.
• Celiac disease.
• Diabetes.
• Food intolerances or allergies.
• Sleep apnea.

“You could be overlooking an underlying issue,” says Zumpano. “If you’ve made some changes and it hasn’t improved, see your doctor.”