May 28, 2021•238 words
Reading time: 1 min
When we expose ourselves to sunlight, we expose ourselves to ultraviolet (UV) radiation.
Prolonged exposure to UV exposure induces skin wrinkling and skin cancer, arguably signs of accelerated ageing (by DNA damage).
UV radiation damages our DNA, accelerating ageing via the DNA damage theory of ageing, where over time, alterations to our DNA accumulate to the point where we either experience ageing, or that our DNA is sufficiently damage so that our DNA repair mechanisms do not function well enough to have slow, normal ageing.
Because our DNA accumulates damage every day, our genome can be used to identify how long we've been born. This is the epigenetic clock.
Wear sunscreen, clothing and minimise sun exposure. Unless you reside in a place/live a life with too little exposure resulting in a deficiency in vitamin D, in which case consider some sunlight every day (a good 20 minutes is reasonable) and supplements. (This vitamin is important for our immune system. For example, vitamin D deficiency is linked to atopic dermatitis, aka eczema).
Further reading: Review article, Atopic dermatitis and vitamin D: facts and controversies*
There are studies that show a positive and inverse correlation between vitamin D deficiency and atopic dermatitis. However, the author of the review does caution about other factors that may lead to the inverse correlation. More evidence does seem to point towards deficiency is linked to atopic diseases.