On sunny days, even if it is not very hot, we fancy lying out in the sun to enjoy the feeling of wellness and to tan. But we must ask ourselves some questions to be sure that enjoying the sun provides benefits for our health instead of risks. Some of the biggest known risks are melanoma and skin aging, two problems directly linked with telomere length.
To avoid these consequences, we should protect ourselves from solar radiation…but do we really know about which type of radiation we are protecting ourselves from?
Three types of radiation arrive to the earth: ultraviolet (UV), visible and infrared. We should only worry about UV radiation because is potentially carcinogenic. This kind of radiation can ionize atoms, excite electrons and generate free radicals that may modify our DNA and therefore, the cell cycle.
Inside UV radiation there are three types: UV-A, UV-B and UV-C. The last one has the most energy, and therefore is the most dangerous, but thanks to oxygen and the ozone, it doesn’t reach the Earth. UV-B is partly absorbed by the ozone, but some reaches us. Even so, almost all of UV radiation that reaches the earth’s surface is UV-A.
And what effects can this radiation produce? The UV-A penetrates the dermis and hypodermis accelerating the skin aging process and can cause skin cancer.
UV-B only penetrate the epidermis, but its effects are cumulative over the years and it is scientifically proven to cause 90% of melanomas, in addition to burns and solar erythema. Both types of radiation can also harm other skin conditions such as rosacea or acne.
More specifically, these are damages that UV-A radiation produces in our organism:
- They induce the production of reactive oxygen species that lead to cell and tissue damage.
- DNA damage.
- They increase the interleukins 1 and 6 levels which have high inflammatory power.
- Collagenase production, that it is responsible for the destruction of collagen, is stimulated.
- It reduces the antioxidant formation (needed to “rejuvenate”).
- It creates more free radicals from the body makes.
All these damages are directly related to the shortening of telomeres and therefore with skin aging.
To avoid these consequences of sun exposure all you have to do is follow the advice of experts: no sun in the hours where the radiation is most intense (11h – 17h) and protect yourself with sunscreen.
Enjoy summer safely!