Did you know that the surface area of your skin is as much as 1.5 to 2 square meters? Sun exposure triggers off the process of melanogenesis i.e. pigment synthesis in the skin. This results in a tan which can be attributed to increased levels of the pigment melanin in the skin. The pigment acts as an effective free radical scavenger and blocks UV radiation.
But is the pigment alone enough to safely bask in the sunshine for hours on end? Unfortunately not. Let’s take a closer look at the problem and bust a few common myths while we are at it.
You should wear sunscreens only in summer
No. Solar radiation can have adverse effects on your skin in the colder months, too. People with sensitive skin which is prone to discoloration should definitely include sun protection in their year-round skin care routines. It is also a great way to prevent skin aging!
Wearing a sunscreen reduce vitamin D synthesis
No. No sunscreen can provide 100% sun protection. Despite protection, some UV radiation will penetrate into the deep skin layers, inducing vitamin D synthesis. In addition, bear in mind that it is impossible to cover your entire body with sunscreen. There will always be some tiny space for UV to squeeze through :).
UV radiation causes faster skin aging
Photodamage of the skin primarily occurs due to exposure to UVA rays, which penetrate deeper than UVB rays. They cause degradation of collagen fibers which provide structural support to the skin and are responsible for its firmness. Photoaging is associated with faster formation of wrinkles and age spots.
The SPF 100 label means that sunscreens reflect 100% of the sunlight reaching the surface of skin
No, it is just a marketing claim. A sunscreen can reflect or scatter at most 98% of solar radiation. Such a sunscreen is labelled SPF 50. Interestingly, there is very little difference between SPF 50 and SPF 30 sunscreens in terms of the reflected radiation (about 2%). Apparently, sometimes there is just no need to pay more :)
Chemical sunscreens cause allergy
Yes! Despite their high wearing comfort, they are proven to have a sensitizing and irritating effect on the skin. They contain many controversial substances (e.g. formaldehyde, PEGI, silicones) which can cause adverse reactions in people with sensitive skin types.
Mineral sunscreens are better
Yes and no. Just like chemical sunscreens, they have their downsides, such as a white residue they leave on the skin. It is caused by two substances: titanium dioxide and zinc oxide. There is indeed no evidence of any allergic reactions to this type of sunscreens. For this reason, they are particularly recommended for children and people suffering from atopic dermatitis.
Natural oils reflect UV radiation more effectively
No. Natural active ingredients cannot replace chemical substances and protect the skin as effectively as regular formulations. Their chief drawback is their low photostability. They quickly undergo oxidation and lose their protective properties.