As Europe experiences an intense heatwave, with temperatures climbing above 40°C (104°F) in several countries, millions of people are relying on sunscreen to protect themselves from the sun. At the same time, social media has revived a familiar debate: Can sunscreen actually be harmful to your skin?

Some online posts claim that sunscreen not only blocks the body’s ability to absorb sunlight but also increases the risk of skin cancer, particularly melanoma, the deadliest form of skin cancer. While this claim has circulated for years, it has gained renewed attention as rising temperatures and climate change expose more people to extreme sunlight.

One widely shared claim alleges that the U.S. National Cancer Institute reported a 200% increase in melanoma cases since sunscreen became widely available in the 1940s, suggesting that sunscreen is responsible for the rise in skin cancer.

However, scientific evidence does not support this claim.

Multiple scientific studies have consistently shown that regular sunscreen use helps reduce the risk of skin cancer, including melanoma. According to Brittany Shafer, spokesperson for the Connecticut State Department of Public Health, there is no scientific evidence linking sunscreen use to an increased risk of cancer.

Experts also point out that the National Cancer Institute has never stated that sunscreen causes melanoma. Reliable melanoma statistics have only been consistently available since 1975. While melanoma cases have increased by approximately 220% between 1975 and 2023, researchers have found no evidence that sunscreen is responsible for this rise.

So why are melanoma cases increasing?

A 2023 international study conducted by scientists from the United States, Germany, Switzerland, and Hungary identified several likely factors behind the growing number of melanoma diagnoses. These include improved cancer detection and reporting, increased time spent outdoors, damage to the ozone layer caused by climate change, and greater exposure to harmful ultraviolet (UV) radiation.

Researchers also note that many people do not use sunscreen correctly. Studies from several countries show that a large number of people apply sunscreen only during summer or when they expect direct sun exposure. Dermatologists, however, recommend using sunscreen every day, regardless of the season.

A 2024 survey in Germany found that 51% of respondents use sunscreen only during the summer months, while 17% said they never use it at all. In the United States, surveys have found that 33% of adults admitted they have never used sunscreen.

The U.S. Food and Drug Administration (FDA), which regulates sunscreen safety and effectiveness, recommends applying sunscreen daily, even on cloudy days or when spending most of the day indoors, as UV rays can still reach the skin through windows and during outdoor exposure.

Health experts emphasize that sunscreen remains one of the most effective ways to protect the skin from harmful UV radiation. They warn that misinformation suggesting sunscreen causes skin cancer may discourage people from using an important preventive measure, leaving them more vulnerable to the real dangers of excessive sun exposure.