We love the warm rays of the sun – the smiling faces we see on a beautiful summer day can attest to that! And yet, despite countless warnings from health authorities that sun radiation poses a very real risk, the message goes largely unheeded. The proof is that the incidence of skin cancer continues to grow in Canada, by 1.8 percent per year in men, and by 1.0 percent per year in women, making up a third of all new cases of neoplasms. While most new diagnoses are not melanomas and are therefore less aggressive (a projected 74,000 in 2011), a projected 5,500 individuals will still be diagnosed with melanoma this year, and approximately 950 will die from it. This is why, without hiding indoors all summer, it is important to protect your skin.
Sun creams act by creating a protective layer that reduces the amount of radiation that reaches the skin. But what sun protection factor (SPF) should you choose?
In order to provide adequate protection, SPF 15 cream must be applied thickly enough, meaning 2 mg/cm2. However, research has shown that most adults only use between 0.4 and 1.5 mg/cm2 of sun cream. SPF 15 cream applied at that thickness would only provide protection equivalent to SPF 2.0 or 7.6, respectively. And if an SPF 50 cream were applied at a thickness of 0.4 or 1.5 mg/cm2 rather than the recommended 2 mg/cm2, the protection would be equivalent to 2.7 or 18.8, respectively.
The conclusion is therefore that since very few people apply enough sun cream, many specialists recommend that people use sunscreens with an SPF of at least 30. To maximize the effectiveness of the product, apply enough cream and repeat the application several times throughout the day: after swimming, when perspiring heavily or at least after every two hours spent in the sun.
Clothing also blocks a great proportion of UV rays. Therefore, if you or your children are considering spending several hours in the sun, a hat and protective clothing are also recommended. Have a great summer!