Sun Exposure & Vitamin D

Depending on where one lives there may be an abundance of sunlight or very little. Either way we must ensure we get the right amount of vitamin D in order to sustain a healthy lifestyle, whether that be from direct sunlight itself or through supplements. If we are exposing ourselves to the sun in order to keep our body’s vitamin D levels high, protecting our skin against sun damage is of utmost importance. However if we are using sunscreen that blocks those harmful UV  rays, particular UVA and UVB, do we still absorb as much vitamin D? We look into these facts and grey areas to build a better understanding.

Does Sunscreen Stop Vitamin D Absorption?

One may think – do I need to wear an SPF if I’m in doors? There is enough protection provided by my day to day cosmetics! These both, are all the common misconceptions surrounding the application of sunscreen as to whether it stops vitamin D absorption or not.

Previous beliefs have been that a high SPF will prevent harmful UV rays from damaging the skin. In turn also preventing the absorption of vitamin D. We will look at why this is not entirely true!

In a recent study conducted by King’s College London, they split individuals into four groups, jet setting off to Spain. All participants wore sunscreen varying from broad spectrum sunscreens with an SPF15 with a good balance of UVA and UVB protection and the second group with a low UVA protection, the third were allowed to use their own sunscreen however were given no instructions on the correct application and finally the controlled group were told to remain home (Poland) and not to go on the trip!

The study showed that after getting the participants blood tested both 24hrs before and 48hrs after they returned from Spain found that both the SPF 15 and broad spectrum sunscreens that had been applied with a sufficient layer showed a much greater improvement of vitamin D levels than a the lower UVA protective sunscreen. This is believed to have happened because the former may transmit slightly more UVB than the latter.

Lead author of the study Professor Antony Young, of King’s College London, said of the study:

The studies found that the experimental studies were conducted using an artificial light source in a lab setting and that actually using natural sunlight exposure concluded that the risks are actually low!

Holly Barber, of the British Association of Dermatologists says:

Summary

In conclusion we should indeed keep our skin well protected by applying a sun cream with an SPF (the British Association of Dermatologists recommend a SPF of 30 as this blocks out up to 97% of UV rays)  and by doing so we are not in any way reducing the absorption of vitamin D into our bodies. If you do feel as though you are not getting the right amounts of vitamin D you can support the lack through a varied balanced diet by including more oily fish, dairy and fortified foods. Other methods can be in the form of vitamin D supplements, guidelines shown by the government recommend a daily vitamin D supplement in order to get your 400IU to support good health.