Sunscreen has been used since the ancient times. Egyptians used rice, bran jasmine and lupine. The ancient Greeks used olive oil. SPF was adopted for use in the 1978 by the US food and drug administration. So, what is in our current sunscreen?

Modern sunscreen includes two mechanisms to prevent UV damage: Organic UV filters and Inorganic UV filters.

Organic filters protect our skin primarily by reducing absorption of UV radiation. These include salicylates, para-aminobenzoic acid, padmate, octinoxate, cinoxate and octocrylene. Inorganic UV filters work primarily by reflecting and scattering light. The most common ingredients are zinc oxide and titanium dioxide. Most sunscreens will include both filters. UVB radiation is responsible for sunburn and tanning. SPF indicates the duration of time your skin can withstand before burning. For SPF 30 this means that the skin can withstand 30X the duration of sun exposure compared to without sunscreen to burn. UVA radiation is harder to measure and is present all year around. UVA penetrates deep into the skin and can cause wrinkles, pigmentation, skin cancer and premature visible skin ageing. UVA is also able to penetrate through windows so you are susceptible to damage even if you are indoors.

However, sunscreen is only effective if you use it properly! It is recommended you apply sunscreen 20 minutes before sun exposure and reapply every 2 hours as well as after swimming, toweling and perspiring. A sunscreen with SPF 30 will filter 97% of UVB and is usually adequate for skin cancer prevention. Broad spectrum sunscreen with UVB and UVA protection is ideal for protecting against skin cancer and anti-ageing. Roughly 30mls (or a shot glass) worth of sunscreen is enough for adequate fully body coverage.

It is worthwhile checking the UV index each day, and ensuring you have sunscreen protection when the levels are 3 or above.