Age spots have been proposed to be the result of glycation, the accumulation of Advanced Glycation End products (AGEs) from interaction of glucose and heat with the collagen in skin, causing melanin deposits with the process being cumulative over time and accentuated by sun exposure. Is that the major cause of age spots?

The observation of advanced glycation end products in many areas of the body is widening scientific interest in this issue. There are indeed potential deleterious effects from too great an accumulation, so that is worth keeping an eye on. But it is not the sum total in explaining origins of age spots, as makes sense from simple observation there is a photoaging response underway because these phenomena appear on areas of the skin exposed to sunlight—the back of the hands and the face, in particular, being most commonly involved. But what is not appreciated in this hypothesis blaming glycation as the origin, is that it is truly necessary that concentrations of viruses locally in the skin are a necessary predisposing factor as well. It is the combination of viral presence representing a kind of impairment or injury, combined with photoaging effects, which trigger the subsequent formation of the age spots themselves. Given that avoiding sunlight totally is not feasible, nor is it a good idea health-wise, being able to administer something to the age spots topically would be ideal in directing a solution to where it is needed specifically, rather than through body-wide exposure of something ingested orally, for example.