system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we get bags under our eyes when we are tired?
gpt
the bags under our eyes are a result of leaky capillaries, combined with the fact that the skin in that area is very thin and more translucent than other areas of the body.

the occurrence of it varies from person to person really. a lighter skinned person who stays up the same amount of time as a darker skin person might look more tired, but they may have stayed up just as long as them.