Shall we sleep after lunch?

Why do you get tired from eating?

After eating, you are often tired and have difficulty concentrating. The cause is obvious: it must be the food. But why does our body react weakly to food intake? There are various theories about this, which are listed below.

Theory 1: The brain receives less oxygen

After eating, there is increased blood flow to the digestive tract so that it can do its job effectively. The processes that are taking place then need energy so that the food can be chopped up and the nutrients can be filtered out and made available to the body.

Because of this, the digestive tract is then supplied with more blood and the blood pressure drops. As a result, the brain receives less oxygen, which can lead to reduced ability to concentrate, tiredness and fatigue. How food affects fatigue depends on how the food is put together. It takes more energy to digest a knuckle of pork than, for example, a soup.

Theory 2: Orexin makes you feel tired

There is an area in the brain called the hypothalamus where orexin is made. Orexin production is dependent on food intake. If you have just eaten something, the distribution decreases. If some time has passed since the last meal, the distribution increases again. So orexin is telling the body that it is hungry.

When hungry, the substance is released and ensures attention and alertness. After eating, the messenger substance is inhibited and tiredness sets in. The messenger substance is a relic from evolution. Since the gathering of food was exhausting, it was necessary to be alert and awake for the hunt. Then there was time to relax until you got hungry again.

Theory 3: Serotonin causes fatigue

Foods like eggs, meat, legumes, and cheese contain a lot of tryptophan. This amino acid ensures the production of serotonin, which on the one hand is known to us as the happiness hormone, but on the other hand also has a sleep-promoting effect. For this reason, ingesting the above foods can lead to fatigue, lack of motivation and poor concentration.

Theory 4: Insulin is responsible for fatigue

Carbohydrates consist of sugar, which we use as fuel for all processes in the body. If you consume sugar, the production of insulin increases in order to lower the previously increased blood sugar level. If you eat high-carbohydrate food, the pancreas will produce more insulin accordingly.

The increased production can be so strong that it leads to a relative hypoglycemia. However, the brain also relies on the sugar in the blood to function properly. The slight hypoglycaemia leads to reduced performance of the brain, which promotes symptoms such as tiredness and fatigue.

Which theory is correct now?

It is not yet possible to say conclusively which theory is the right one. Rather, it is assumed that it is an interplay of theories that is responsible for the tiredness after eating.

What can you do about tiredness after eating?

So that you do not fall into a "eating coma" after eating, you should pay attention to a few points to prevent tiredness:

  • Eat slowly
  • Don't eat too much at once - it's better to have several small meals
  • Fresh air
  • If you get enough sleep, your body will be more productive anyway
  • Moderate exercise after eating

"After eating you should rest or take a thousand steps" - this wisdom is still valid today and should be heeded as much as possible to avoid excessive fatigue.