There are a few reasons that make you sleepy after consuming food.
1. Excitement of vagus nerve:
Normally, it’s a natural reaction of our body to be tired after eating. The vagus nerve, which is related to sleeping gets excited after we eat in order to provide assistance for digesting the food.
While the vagus nerve facilitates the peristalsis of intestines, it also makes us want to sleep. It is more obvious after having lunch than any other meals.
2. Blood and oxygen decrease in our brain:
After consuming food, our body needs energy to digest all the things we eat. Therefore our central nerve system will make more blood flow to our stomach and intestines, enhancing the absorbing function.
In the mean time, the blood amount in our brain in relatively less than normal situation. Less blood flow means less oxygen. Less oxygen makes us want to sleep.
3. Increased carbon dioxide concentration:
After eating, our digestive organ functions, therefore producing more carbon dioxide. The carbon dioxide in our blood stimulates the nerve system in our brain, making us feel tired.
4. The decreased secretion of orexin:
While eating, a hormone called orexin will be secreted by our brain. This kind of hormone participates in the adjustment our of sleeping cycle. After consuming large amount of carbohydrates, the glucose will suppress the secretion of orexin thus making us want to sleep.
IS IT NORMAL TO BE TIRED AFTER EATING?
Yes, it is. We do not have to adjust it intentionally. We should take some rest before doing other things to make the digestive organs function well.
