- Many people only use sunscreen during the summer months
- It is, however, important to use it throughout the year when exposed to the sun
- There is high-quality evidence that using sunscreen is an effective measure against developing skin cancer
Summertime means the weather is ideal for outdoor activities, but it also means the sun’s rays are more powerful and dangerous than during the rest of the year.
Summer is when we tend to reach for the sunscreen because we are more aware of how harmful the sun can be. However, Canadian dermatologists recently published a review of the general use of sunscreen – highlighting why it is important to use it at all times.
The researchers used existing studies as evidence to construct the review, providing details on the effectiveness and safety of sunscreen.
Prevention is better than cure
Earlier studies, dating back to the 1990s, have already shown that most skin cancers are caused by overexposure to the sun. “Exposure to ultraviolet radiation is directly harmful and has been associated with the development of skin cancers,” the researchers wrote in their review.
Researchers therefore advise that everyone older than six months should use sunscreen with an SPF (sun protection factor) of 30 or more. It is recommended that babies younger than six months wear protective clothing or avoid the sun because of the potential risk of absorbing some of the sunscreen ingredients.
How much sunscreen should be applied?
According to observational studies, many of us do not apply enough sunscreen, and that we often only apply about 20–50% of the optimal amount. They did add that creams with a higher SPF tends to compensate for under-application.
In all, the amount of sunscreen required and periods between applications depend on the type of sunscreen used and activities conducted. For example, when swimming, reapplication is recommended, and a water-resistant sunscreen is advised.
How effective is sunscreen in preventing skin cancer?
“Experimental studies from the 1980s and 1990s showed that sunscreens protect against cell damage consistent with carcinogenesis in animal models," the researchers stated.
"A well-conducted community-based 4.5-year [randomised control trial] of 1 621 adult Australians, with follow-up for more than a decade, found a 40% lower incidence of squamous cell carcinomas among participants – randomised to recommended daily sunscreen – compared with participants assigned to use sunscreen on a discretionary basis."
The researchers expressed that this can be regarded as high-quality evidence that using sunscreen is a preventative measure against developing skin cancer.
In their concluding remarks, the researchers expressed that “physicians should counsel patients on photoprotection strategies, including avoiding the midday sun, seeking shade and wearing protective clothing, as well as using sunscreen if sun exposure cannot be avoided.”