We’ve all done it, enjoyed a delicious meal only to nod off in a comfy chair for a while. For some of us, this is just a habit. But for others, it’s unavoidable. So what is it about food that can make us so sleepy?
When we’re eating, the stomach is producing gastrin, a hormone that promotes the secretion of digestive juices. As the food enters the small intestine, the cells in the gut secrete even more hormones (enterogastrone) that signal other bodily functions, including blood flow regulation.
But what does this have to do with sleepiness? Well, as we’re digesting our meal, more of our blood is shunted to the stomach and gut, to transport away the absorbed newly digested metabolites. This leaves less blood for the rest of the body and can cause some people to feel a bit “light-headed” or tired.
Still, the body is a lot more sophisticated than that; it doesn’t respond to food volume alone. What you eat is just as important as the size of your meal. (Post continues after gallery.)
Biochemistry and sleep
For many years now, researchers have been investigating the link between food and sleepiness, but from another perspective. If we understand more about people’s sleep patterns, we might gain insight into what causes some people to put on weight and develop diseases such diabetes and atherosclerosis (a disease of the arteries that develops with fat deposits in artery walls).
We’ve known for many years that meals with an imbalance of nutrients – that are rich in either fats or carbohydrates – are associated with feeling sleepy. But this is not the case when nutrients are balanced or the meal is rich in protein. And that leads to the burning question: what is causing this effect?