When you’ve shopped for sunscreen, you have probably noticed products with very high sun protection factor (SPF) ratings. As a redhead, do you assume 100 SPF will protect your fair skin better than 30 SPF? Four dermatologists are here to break this common misconception.

What Is SPF? 

SPF refers to the ability of a sunscreen to block ultraviolet B (UVB) rays, which cause sunburns, but not UVA rays, which are more closely linked to deeper skin damage. Both UVA and UVB contribute to the risk of skin cancer.

The SPF rating is a measure of the time it would take you to sunburn if you were not wearing sunscreen as opposed to the time it would take with sunscreen on. Florida dermatologist James M. Spencer, MD told WebMD, “SPF is not a consumer-friendly number. It is logical for someone to think that an SPF of 30 is twice as good as an SPF of 15 and so on. But that is not how it works.”

Why the American Academy of Dermatology considers SPF 30 the gold standard for sunscreen

How to be a Redhead had the opportunity to speak with three dermatologists who fully explain why redheads can using SPF 30. Debra Jaliman M.D., a board-certified dermatologist and author of the book Skin Rules says, “An SPF 30 offers sunscreen protection for UVB light of 97%. An SPF 50 offers sunscreen protection of 98% for UVB light. An SPF 100 offers 99% percent protection for UVB light. You notice the differences in percentage are not that great yet the numbers for SPF are very great.”

Dr. Jaliman also points out that the SPF count tells a consumer nothing about UVA light which also causes skin cancer and causes sun damage to the skin.

She also points out an interesting fact that many people who use SPF 70 hardly ever re-apply. “There was a study of people who used SPF 70 sunscreen and use 1/2 as much sunscreen. What they found was this was an equivalent to not an SPF of 35 but actually the square root of 70 which is an SPF of 8.4,” says Dr. Jaliman. “The American Academy of Dermatology considers the gold standard for sunscreen to be an SPF 30.”

The other problem with using high SPF values is many people will not reapply their sunscreen, and higher SPF means more chemicals. “The recommendations are that you reapply sunscreen every two hours. The other problem is many choose, for example, SPF 70 and it may not block both UVA and UVB rays, and the sunscreen is loaded with chemicals to produce a high SPF factor.

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Why the FDA will get rid of high SPF numbers 

“High SPF’s offer only minimal advantages over SPF 30,” says Dr. Alan J. Parks founder of Eastside Dermatology & Skin Care Center. “The FDA will actually be doing away with higher number designation in the near future. Best protection is with a physical blocker such as zinc oxide.”

Why SPF 30+ to 50+ has practically no change in formula

Dr. De Fiori, a leading dermatologist for the Rosacea Treatment Clinic says, “The maximum SPF number a product can state has varied over time. I noticed that when many manufacturers increased their product ratings from 30+ to 50+ there was no change in the formulas because the concentration and types of sunscreens being used remained the same.”

The lesson here is to use SPF which protects again both UVA and UVB rays, and using SPF 30 is doctor recommended; but make sure to reapply every 1-2 hours to keep your fair skin protected.

Rock it like a Redhead! 

Photo Credit: The Daily Lil Blog