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lethargy nutrition

Food that can cause lethargy

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lethargyPhoto: Shutterstock

It’s usually right around mid-day, after you’ve had a satisfying lunch, when you find yourself feeling lethargic and sleepy. Unbeknownst to many, the types of food we eat are actually the culprits behind that afternoon slump.


That cup of coffee you have in the morning to keep yourself awake is surprisingly one of the sources of mid-afternoon lethargy.  Although caffeine provides you with a feeling of alertness, it’s simply a temporary stimulant, so that shot of espresso, your can of energy drink and the like will have an opposite effect later in the day.

Additionally, coffee dehydrates you. Since almost all systems in the body depend on water, you should stay hydrated by drinking lots of water in order to prevent lethargy.

lethargy Photo: Shutterstock

White Bread

Although your body needs carbohydrates to function, refined carbs like white bread, pasta and pancakes can cause a quick rise in blood sugar, followed by a plunge in insulin levels. This can lead to fatigue, drowsiness and nausea.

Instead of going for refined carbs, opt for some oat bran and nuts to start your day. Alternatively, whole-grain bread is also a good option to avoid an energy spike and crash later in the day.

lethargyPhoto: Shutterstock


Many people turn to sugar when they’re looking for that instant boost of energy, but the jolt is very short-lived. As such, going for that sweet treat after lunch will likely put you to sleep faster than the amount of time it helps you to stay alert.

You might feel energetic for a short while due to the increased metabolism, but as soon as the sugar is burnt, you will start feeling very lethargic.

When you eat sugary foods, it causes a rapid spike in blood sugar. In response to that, your pancreas floods your bloodstream with insulin. The insulin rapidly lowers your blood sugar, and lethargy kicks in.


Bananas are not always the best choice when you’re trying beat a slump. They are rich in potassium, which might help in nerve function and heart health, but bananas are also high in magnesium, an essential mineral that facilitates sleep.

Making changes to your diet could definitely be the difference between an energetic or listless day, so if you find yourself lacking motivation or performing badly, consider cutting out processed, sugary or high-fat food.

Research demonstrates that by switching those out for more vegetables, lean meat and fruits, you can improve your physical and mental capabilities, as well as enhance cognition and help your focus.