If you only sleep 5 hours instead of 8, your body might produce more of a hormone that makes you feel hungrier — even if you’re the same weight, age, or sex as someone who sleeps longer.

When adults between 30 and 60 don’t get enough sleep over a long time, their body makes less of a hormone that tells them they’re full; but if they miss a night of sleep, their body makes more of a hormone that makes them feel hungry—so different kinds of sleep loss affect hunger in different ways.

If you don’t get enough sleep just one night, your body makes more of the hunger hormone and less of the fullness hormone, which might make you feel hungrier the next day.

The hunger hormone ghrelin doesn’t seem to affect how the body burns fat vs. carbs after eating, how active someone is, how fit they are, or their eating habits like restraint or hunger feelings.

People who sleep only 5 hours a night tend to have lower levels of a hormone that tells your brain you're full, compared to those who sleep 8 hours — even if they're the same weight or age — which might make them feel hungrier.

If you don’t get enough sleep for 8 days, your hunger hormones don’t change much—so if you end up eating more, it’s probably not because these hormones are telling you to.