how do our stomachs know how much food we eat on average, and will produce the hunger response when we eat less than usual?

Question

For example, I went on a trip last week, and ate more than my usual amounts, as well as an additional meal (breakfast).

Now, when I came back, the usual volume of food I ate prior to the trip is not enough to satiate my stomach, as it produces the feeling of hunger a lot earlier than my usual meal times, since I dont eat breakfast.

Clearly my old meals were enough for my body prior to the trip, but now, my stomach “knows” I can eat more if I wanted to, and provides the hunger response.

In: 4

Answer 1

Stomach doesn’t “know” anything, it’s your brain that receives all sorts of sensory information to make you feel hungry. And it’s not just from the stomach, but also from the blood and from the various organs involved in digestion and water retention (intestines, liver, kidneys, etc.).

Ultimately the cells in your body need not just energy (in the form of glucose sugar levels in your blood), but also vitamins, minerals, water, etc. The stomach can report its contents through the nerve endings attached to it, and through the enzymes and hormones that can be released into the blood stream, but other organs report too.

So yeah, it’s a matter of carbs, fats, proteins, vitamins, water amounts… and also how much effort you’ve been making (energy consumption by the cells in your body), and even expectations (the circadian rhythm, hungry during the day, not so hungry at night when you’re supposed to be sleeping).