Will I get paid for overtime? web data mining research papers If you apply sunscreen correctly (see question 3), SPF 50 offers the maximum protection necessary. You’re seeing SPF 80 and even SPF 110 on shelves because of “marketing, marketing, marketing,” says Bruce Katz, MD, a dermatologist in New York City. Companies know that higher numbers make you think you’re getting a significant surplus of protection, even though you’re not. But the FDA has caught on to this strategy and proposed a rule making “50 ” the highest SPF value allowed. The rule hasn’t been approved yet, but many manufacturers are probably betting it willÃ¢ÂÂthey’re already distributing products labeled SPF 50 , even as they continue to sell higher numbers.