Paradox of Sunscreen: A false sense of security in the sun that can really burn you
The phenomenon known as the “paradox of sunscreen” pertains specifically to UVA light. In spite of the widespread use of sunscreen over the past 30 years, photoaging and skin cancer rates have continued to rise. If sunscreens were effectively protecting us, this would not be the case.
The reason this phenomenon exists is the false sense of security people often get from using sunscreen. While a high-SPF sunscreen might prevent a UVB-induced sunburn, it doesn’t necessarily offer the same protection when it comes to UVA rays. So, thanks to a product with an SPF 30, you might have spent three to four times longer in the sun, believing you were protected. However, if your sunscreen blocked mainly UVB light and, to a much lesser extent, UVA light, you could easily have been exposed to three to four times more UVA light. Because UVA light is present in one-hundred-fold greater amounts in the environment than UVB light, the profound damage that is associated with UVA, such as premature aging and melanoma, has been on the rise.
Fortunately, new sunscreen rules are designed to address the paradox of sunscreen with a new efficacy testing for “broad-spectrum” label claims. As of December 2012, in order for a sunscreen to claim broad-spectrum activity, it must demonstrate effective UVA protection in proportion to its SPF claim. If a sunscreen does not pass the broad-spectrum test, it is required to bear a warning that reads, “Skin cancer/skin aging alert: Spending time in the sun increases your risk of skin cancer and early skin aging. This product has been shown only to help prevent sunburn, not skin cancer or early aging.”
Keep in mind that even with the best SPF you still need to be sun smart. That means generously reapplying sunscreen throughout the day and seeking shade as often as you can when you are outdoors.