Products considered over-the-counter drugs in the United States and as such are strictly regulated by the FDA. Sunscreens provide protection from sunburn and some amount of sun damage. There is a great deal of confusion regarding the efficacy and use of sunscreens. The FDA instituted new regulations that were supposed to take effect in 2002, but most of them did not come into play because the FDA’s Final Sunscreen Monograph was, for various reasons, never officially updated. According to the FDA’s July–August 2002 issue of Consumer magazine, “Under the new regulations manufacturers will no longer be allowed to [use] … confusing terms such as ‘sunblock,’ ‘waterproof,’ ‘all-day protection,’ and ‘visible and/or infrared light protection’ on these [sunscreen] products. In addition to these changes … tanning preparations that do not contain a sunscreen ingredient [are required] to display the following warning: ‘Warning: This product does not contain a sunscreen and does not protect against sunburn. Repeated exposure of unprotected skin while tanning may increase the risk of skin aging, skin cancer, and other harmful effects to the skin even if you do not burn.
“To figure out how much protection a sunscreen provides, most consumers turn to a simple number: the SPF, or sun protection factor, listed on the label. Studies show that most consumers understand that the higher the number, the more the product protects the skin.”
The FDA then goes on to say: “Unfortunately, studies also show that people often have the mistaken notion that the higher the SPF number of the sunscreen they use, the longer they can stay—and will stay—in the sun.… Sunscreen should not be used to prolong time spent in the sun. Even with a sunscreen, you are not going to prevent all the possible damage from the sun. Some of the newer research in the last several years shows that [for] the sub-erythemal doses [exposure to the sun that does not cause reddening of the skin], as little as one-tenth the energy needed to get a sunburn, starts the process of skin damage of one sort or another.
“The public under-applies sunscreens by as much as half of the recommended amount, concluded a study published in the Archives of Dermatology. Consequently, the study argued, consumers are receiving only half of the SPF protection they believe the product provides.” The issue of liberal application has been confirmed in other research as well (Source: Photochemistry and Photobiology, July 2001, pages 61–63).
sun protection factor