This. Look up tear trough fillers, OP. There are ways around this (assuming it's not hyperpigmentation).It's also caused by fat loss in the face which gets pronounced as you get older. In that case the skin under the eye sinks a bit causing a shadow effect. Facial fillers would help in that case. If it bothers you see a dermatologist and ask them to recommend a solution.
I said it in the very first post lolOkay.. So the tip nobody gave you... Get out in the sun more often.
Could be "dairy face."
Look it up! It's a real thing!
Wear glasses. Even if theyre non prescrip.