There isn’t much evidence to conclusively prove that daily sunscreen use can prevent most skin cancers. But don't throw out all your sunscreen stash just yet.
More than 3 million Americans develop skin cancer each year. Our understanding of how skin cancer develops is limited; the only known medical strategy to lower the risk of developing skin cancer is to avoid skin damage from the sun. There are several ways to accomplish this: stay inside during the middle of the day, wear clothing and hats to cover your skin, and – of course – use sunscreen.
But the evidence of how well sunscreen protects against skin cancer is mixed. There isn’t much evidence to conclusively prove that daily sunscreen use can prevent most skin cancers, a research review concludes.
Researchers categorize skin cancers into two main types: melanoma and non-melanoma. Some data show that sunscreen is more useful in preventing non-melanoma skin cancers.
There is also limited evidence that sun exposure and sunburns increase one’s risk for developing melanoma, the deadliest form or skin cancer. But there are also many studies that find sunscreen does not reduce one’s risk for developing either type of skin cancer.
So, what and who should we rely upon the most when choosing a product for skin protection from the sun rays? Read on to clear this out along with us.
Not all sunscreens are created equal
It is quite obvious that there is a difference between preventing sunburn and preventing other types of skin damage. Some sunscreens can do both, but others can’t.
Sunscreen is essential for staying protected in the sun – but recent research suggests some of the ingredients could be improved.
Some researchers have raised concerns that, despite being an undeniably important tool in our fight against skin cancer, the formulation of sunscreen may need to be improved to contain safer ingredients – and, at worst, some sunscreens could be damaging our health.
Now, the argument here is not against sunscreen. Sunlight can damage the skin, and sometimes lead to cancer, so it’s prudent to protect yourself. The problem is that good data on precisely how effective sunscreen is, in what formulations, and for which people, is significantly more scarce than most consumers have been led to believe — though scientists and public health officials have known this for a long time. They simply chose to gloss over the uncertainties in deference to a highly profitable industry and an easy-to-digest health message.
Meanwhile, researchers have known for at least two decades that the chemicals in many sunscreens get into the blood and potentially cause harm.
Despite the mixed evidence, the American Academy of Dermatology recommends sunscreen to prevent skin cancer. But which ones are the safest and work the best?
The safety issue
The non-profit Environmental Working Group publishes an annual sunscreen report that rates more than 1,000 sunscreens and 600 moisturizers. The products are labeled on a scale of one to ten based on industry, government and academic data sources and a review of the technical literature on sunscreens.
The products are rated based on the potential health hazards associated with listed ingredients and the amount of sun protection the product offers. The report also includes an extensive online database that allows you to search for a sunscreen product.
This year’s report has some interesting observations summarized in a tip sheet for consumers. Among them are the following:
- Don’t be fooled by high SPF. Products labeled with a high-SPF only provide marginally-better protection compared to products with a lower SPF. For example, an SPF 60 sunscreen does not provide twice as much sun protection as an SPF 30 product.
- Many sunscreens include a vitamin A additive that may speed the development of skin cancer. The sunscreen industry adds a form of vitamin A called retinyl palmitate to some sunscreen products to help prevent aging. But studies show it may trigger the development of skin tumors and lesions when used on the skin in the presence of sunlight.
- Sunscreen doesn’t protect skin from all types of sun damage. The sun’s ultraviolet rays cause damage other than sunburns by generating free radicals that damage skin cells. Sunscreens help, but not completely. Not applying enough sunscreen, not applying frequently, and using products with poor UVA protection can lead to skin damage we cannot see with the naked eye.
- Some sunscreen ingredients affect hormone production and cause allergies. Sunscreens are designed to penetrate the skin so they will last, but this often means they are absorbed by the body. Studies show some of the ingredients may disrupt hormone production or cause skin allergies.
In recent years you may have also heard a rumor that sunscreen can in fact cause skin cancer. Most of these rumors appear to be either myths or mistakes, with only the flimsiest of evidence behind them.
Making healthy choices
As you can see, the question of whether sunscreens really protect us from all kinds of harmful rays is quite complicated. What we do know with the greatest certainty is that sunlight can damage the skin, so it’s prudent to protect yourself. In a statement about the FDA study, the Skin Cancer Foundation echoed Johnson & Johnson’s assertion that sunscreens have been used for many years without evidence of harm: “There’s simply no justification for abandoning sun-safe behaviors.”
Choosing a sunscreen that fully protects your skin from the sun without increasing your risk of other health problems can be a tricky proposition. But a little bit of research can go a long way into finding a product that is safe and effective. As long as sunscreen is not hazardous, the evidence shows it may help lower your risk of developing skin cancer.
For people concerned about possible health risks, experts advise using mineral sunscreens until we have better safety data on the chemical versions.
In addition, both medical societies and the experts warn against relying on sunscreen like it’s an invincible shield, which it’s not. Seeking shade, avoiding the direct midday sun when UV intensity peaks, and wearing UV-protective clothing, broad-brimmed hats, and sunglasses are also recommended.