The ABCs of SPF

Remember the days of baby oil for suntan lotion? How about those tinfoil reflector boards people used to harness every ray of sunshine?

And then there's a quote from the late Greek shipping tycoon Aristotle Onassis: "To be successful, keep looking tanned."

But we now know a lot more about the dangers of too much sun, such as premature skin damage and potential skin cancer risk.

We even know our sunscreen has to have a good level of sun protection factor, or SPF, to protect us from sunburn. But figuring out what that SPF level should be is getting increasingly confusing.

Until recently, we were told that SPF 30, if properly applied, was sufficient. But now, store shelves are stocked with sunscreens ranging from SPF 45 to 60. This summer, a couple of companies are even marketing SPF 70 in Canada.

When we checked store shelves, we discovered those bottles of sunscreen with higher SPFs can cost several dollars more than the same brand's lower SPF sunscreens.

So, is it worth spending more money for sunscreens with a higher SPF?

Is higher better?

"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."

Keeping burn at bay

Rivers says the best protection is limiting your time in the sun and wearing protective clothing, including a wide-brimmed hat. 

As for sunscreens, it's important to put enough on.

"Well, here in Vancouver, if you're going to Wreck Beach and want to cover your entire body, one application is 30 millilitres, or an ounce," Rivers said, referring to the city's nude beach.

"And when you realize a bottle may contain three or four ounces of product, it doesn't go very far." 

Sunscreen also has to be reapplied if you go swimming or are sweating a lot.

At the Canadian Cosmetic, Toiletry and Fragrance Association, Michael Patton tells us: "There is increasing pressure — and it is mostly market-driven from consumers — to find higher and more effective ways to block out the damaging rays from the sun."

As for whether there's a negligible difference in protection from sunburn between the cheaper SPF 30 products and the more expensive SPF 70 sunscreens?

"Well, it all comes down to: consumers can make whatever decision they want," says Patton.

Meantime, the SPF creep continues. Health Canada tells us it has approved a sunscreen with an SPF as high as 110.

Even higher SPFs may eventually hit the market. In the United States, sunscreens with SPFs over 100 are already on store shelves.