How to choose the perfect sunscreen

The best anti-aging method is to prevent your skin from getting damaged in the first place. Sunscreen is by far the most important element of any anti-aging protocol while decreasing your risk of developing skin cancer. Up to 80% of fine lines and wrinkles result from UV damage. UV also causes skin blotchiness, sagging and roughness.

There are so many sunscreens available from the types you can find at your local supermarkets to the more upmarket daily moisturisers. In this article we will discuss what makes a perfect sunscreen.

In order to understand what makes a perfect sunscreen we need to understand how it gets damaged by the sun. Ultra violet radiation is invisible energy that is released by the sun. Its made up for three wavelengths, UVA, UVB and UVC. Both UVA and UVB can reach the earths surface and cause cancer. In fact, most of the UV rays you come in contact with are UVA with a small amount of UVB.  UVA has longer wavelengths than UVB which means it can penetrate deeper into the skin. It is the main cause of skin damage while UVB is the main cause of skin burning when exposed to the sun. In the past, sunscreens would only protect against UVB but with an increased understanding of skin, many sunscreens are available that now cover both spectrums.

Suncreens are available as both physical and chemical suncreens. Chemical suncreens protect the skin by absorbing UV light and changing it to another form of energy i.e. chemical energy. They can release free radicals when exposed to UV rays that may also be damaging to the skin. They also are more likely to cause allergic reactions and irritation in sensitive skin than physical sunscreens. The benefit of chemical suncreens compared to physical suncreens is that they are much thinner than physical suncreens and therefore easier to spread on the skin for good coverage.

Physical sunscreens sit on top of the skin and act by reflecting the UV rays. The main active ingredients in physical suncreens are zinc oxide and/or titanium dioxide. Combinations of both zinc oxide and titanium dioxide may provide the most broad spectrum coverage. The main problem with physical suncreens is that they tend to be thick and can leave a white cast on the surface of the skin. This can cause the skin to have a ghostly appearance.

While any sunscreen is better than none, a physical sunscreen is probably a better choice for avoiding irritation and the potential of chemical damage when chemical sunscreens are exposed to UV radiation.

More expensive physical suncreens come in micronized and nano zinc/titanium dioxide. This means that particles are smaller and are able to spread more easily. Nano particles are smaller than micronized particles and are able to spread the easiest. They are almost invisible when applied to skin.

One concern with nano-particle suncreens was whether it was possible for the nano-particles to reach the deep layers of the skin and cause damage to skin cells. This is because, like chemical sunscreens, nano-particles can release damaging reactive oxygen species when exposed to UV. However, even nano-particles are blocked off by the outer skin layer (epidermis) and cannot reach the deep skin. High end nano-suncreens can also have special coatings to reduce the formation of reactive oxygen species and contain anti-oxidants to neutralise the reactive oxygen species.

Another factor to consider is that while these nano-particles cannot penetrate the skin, they can enter the pores (exit holes for hair follicles) and enter into the hair shaft. Particles of titanium dioxide nano-particles have been found in several studies in people with frontal fibrosing alopecia, a type of scarring hair loss. This may explain why this type of hair loss is more common in women i.e. because titanium dioxide nano-particles are common in female cosmetic products. At present it is not known whether the nano-particles are causing the hair loss or not. However, it may be better to err on the side of caution and stick to micronized rather than nano-particle physical suncreens.

To summarise, in our opinion, the best sunscreen for avoiding photodamage is probably a micronized zinc sunscreen where the zinc particles are coated. A tinted zinc sunscreen can help counteract the whitish mask effect found with micronized zinc sunscreens.

Osmosis Protect is a non-nano, coated zinc that offers sheer, long-lasting coverage.

Uberzinc from Synergie Skin is a great hydrating moisturiser formulated with over 20% pure Zinc Oxide offering broad spectrum UVA and UVB sun protection. It does not clog pores and has added green tea extract for anti-oxidant properties. It is slightly tinted and so does not leave any white masking when applied to the skin.

Both of these suncreens are available at Face Doctors Clinic.