What are the causes of bags under the eyes, and is it serious?
What should I do to prevent them, and what actually makes the skin sag?
To the best of our knowledge, it just happens to some people and it's harmless.
With aging, the tissues around your eyes, including some of the muscles supporting your eyelids, weaken. Normal fat that helps support the eyes can then move into the lower eyelids, causing the lids to appear puffy. Fluid also may accumulate in the space below your eyes, adding to the swelling.
Unless there are additional symptoms, like itching or redness of the eye, there is no cause for concern. Some things can make it worse, like hot weather, and some things can make it look worse on some people, like people with very light skin.
The medical expression is "mild periorbital swelling", by the way. Searching for it in medical databases will mostly lead to getting information on the rare cases where it was a symptom of a serious illness, though.
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