Cross-linking, (also known as glycosylation) attributes aging to chemical changes that happen gradually as proteins, structural molecules, and DNA develops detrimental chemical bonds (aka cross-links) to each other.
Cross-linking issues arise when glucose binds to protein. This process occurs under the presence of oxygen, and as we age there are increased odds that oxygen comes in contact with glucose and protein to activate the cross-linking transition.
This is somewhat similar to how apple slices (a glucose-rich food) will gradually turn yellow and brown as they are exposed to oxygen in the air.
Cross-linking of proteins may also play a role in the hardening of collagen and cardiac enlargement, increasing the risk for cardiac arrest.
Cross-linking is also associated with stiffening of blood vessel walls, delayed wound healing, reduced joint mobility, and changes in the lens of the eye.
In addition to these potentially serious implications, many believe that cross-linking is responsible for age-related skin changes including wrinkles and reduced elasticity.
As we grow older, sugar-derived bonds, or crosslinks, are formed between the proteins that make up our tissues, making tissues more stiff. Stiffer tissue is less capable of performing its function than soft, supple tissue, especially in blood vessels, the lungs and the skin.