Higher SPF sunscreens don't block as much as you may think

SPF 40-70 cost a few dollars more than SPF 15-30 but is it worth it?

An article from CBC news states that SPF sunscreens over 30 only protect your skin by a percentage more.

"I think part of the ploy is marketing," says Vancouver dermatologist Dr. Jason Rivers. He says consumer are under the misconception that "high is better, more is better."

Rivers says the improved protection from sunburn when using a sunscreen marked SPF 60 or 70 is minimal because an SPF 30 already blocks out most of the ultraviolet B radiation.

"If you double that number, you're only increasing that by a per cent or more," said Rivers.

A sunscreen with an SPF of 30 gives you 96.7 per cent protection from sunburn. Sunscreen with an SPF of 70 gives you 98.3 per cent protection.

And then there's the possibility that sunscreens with high SPF numbers give people a false sense of security in the sun.

"There is that potential," says Rivers. "Especially for younger individuals. There have been some studies that show using a higher SPF sunblock encourages people to stay out longer."

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