We're not 20 again, we've gained and lost weight a lot, our skin has literally been stretched to capacity and then left empty and refilled again until it has lost much of its capacity to shrink.

I don't consider myself being among the "older" people here (I'm 29), but now that I've lost some 25 pounds I see lines around my eyes that weren't there four months ago. Well, I for one never noticed them. My face was chubbier, so I would think that they were hidden somewhere beneath the fat.

There are many factors involved in skin damaging process: age, sun, wind, rate at which you lose weight, past dieting history, surgeries. Many people who lose a lot of weight, especially when they are older, have surgery to cut it off. Richard Hatch, the guy who won the million dollars on Survivor and also lost 140 pounds along the way, had the surgery to take off the excess skin around his waist, and he's young and athletic.

Even life-long thin people get wrinkles and sagging skin as we age, there really is such a thing as gravity. Probably we're fat because we never did do much exercise to keep our skin toned, among other reasons. So a balance diet to keep you good weight is very important. But it seems that exercise is the key of everything, starting to optimal weight and ending with toned skin and wrinkles removal.