Saying do not eat sugar is like asking someone to not make any noise when they fart, graphic I know but trying to get a point across here. If you're a sugar junky chances are you have fine lines already even if you're only in your 20's. If you're a sugar junky and you're in your 30's chances are those fine lines have already evolved into actual wrinkles. That's because sugar causes glycation inside our body.
-Excerpt from Elle Magazine Sugar and Aging, the truth about Glycation
The science is this: When you have sugar molecules in your system, they bombard the body's cells like a meteor shower—glomming onto fats and proteins in a process known as glycation. This forms advanced glycation end products (commonly shortened, appropriately, to AGEs), which cause protein fibers to become stiff and malformed.
The proteins in skin most prone to glycation are the same ones that make a youthful complexion so plump and springy—collagen and elastin. When those proteins hook up with renegade sugars, they become discolored, weak, and less supple; this shows up on the skin's surface as wrinkles, sagginess, and a loss of radiance.
So put down that donut, drop that candy bar not only will it make you fat it will make you OLD.