Skin cancer is on the rise. Could climate change be to blame

Getty Images

Skin cancer cases in the United States more than tripled from 1975 to 2021, despite technological advances in sunscreens and public awareness of the risks of sun exposure. In Canada, melanoma - the deadliest form of skin cancer - increased by 17% in 2024 alone.

How can this be?

It's likely caused by a combination of factors, but some studies suggest that the increasing temperatures due to climate change and intensifying ultraviolet (UV) radiation exposure resulting from air pollution could be contributing to the problem.

"The ozone layer acts as a broad-brimmed hat for the Earth," explains Eva Rawlings Parker, MD, an assistant professor of dermatology at Vanderbilt University Medical Center in Nashville, Tennessee, who specializes in climate change-related skin diseases. "It blocks UV radiation, and it's been degraded by chlorofluorocarbons. The manufacturing [of these compounds] is restricted now, but they're very long-lived and act as potent greenhouse gases. What we're now seeing are synergistic effects of three environmental impacts: increased UV, air pollution, and heat."

Parker has seen not only an increase in skin cancer, but also exacerbations of other skin diseases, such as atopic dermatitis and psoriasis, because of heat, air pollution, and exposure to wildfire smoke.

"Skin being the largest organ, it is the main barrier against the big, bad world," she says. "A lot of physicians don't realize there are more than 3,000 skin diseases. There are skin health impacts we can see from the environment on many of these diseases."

Climate change could also be increasing the time spent outdoors in regions that used to have fewer warm-weather days, contributing to an increase in skin cancers in northern regions like Canada and Scandinavia, according to a 2025 research paper.

"The sun is addictive. We crave the sun," says Ivan Litvinov, MD, PhD, a dermatologist at St. Mary's Hospital Centre, affiliated with the McGill University School of Medicine, in Montreal. "When the sun hits your skin, it produces endorphins, so it feels good to be in the sun. It's a lot of the reason, perhaps, why we want to tan."

But Litvinov stresses that there's no such thing as a healthy tan. He's studied a phenomenon called the sunscreen paradox, where people who report sunscreen use have higher rates of skin cancer than those who don't. This is because many people who use sunscreen spend more time outdoors and don't apply enough of it, he says.

"Think of [sunscreen] as a seat belt," Litvinov says. "If you're speeding, if you're drinking alcohol, are you safe? You're not safe."

Rising risk

Skin cancer is the most common form of cancer in the United States; an estimated 1 in 5 Americans will develop skin cancer at some point in their life, according to the American Academy of Dermatology (AAD). That includes the three main types of skin cancer: basal cell carcinoma (BCC), the most common kind, which presents as a pearl-like bump or pink patch of skin; squamous cell carcinoma (SCC), the second most common kind, which appears as a red bump or sore; and melanoma, the deadliest kind, which can grow from an existing mole or a new dark spot.

BCC and SCC are highly treatable, especially when caught early. Melanoma, which is expected to cause the deaths of 8,510 Americans this year, has a 99% five-year survival rate if it is treated before it reaches the lymph nodes, but only a 35% five-year survival rate if it has spread beyond the lymph nodes and into distant organs, the AAD reports.

Melanoma is still uncommon (people with white skin have a 3% lifetime risk of developing it; people with darker skin have less than a 1% lifetime risk), yet rates for melanoma doubled in the United States from 1982 to 2011. Though Black Americans are less likely to get melanoma, they die at disproportionate rates, mostly due to late detection.

From 1979 to 2010, UV radiation increased about 3% across the globe, with the greatest increases in midlatitude areas such as the northern United States and Canada, according to one 2025 study in Nature.

The popularity of indoor tanning has also taken a toll. Women under age 30 who use tanning beds are six times more likely to develop melanoma than those who don't, notes the AAD.

Adolescents are also particularly vulnerable. Getting five or more blistering sunburns between ages 15 and 20 increases lifetime melanoma risk by 80% and other skin cancer risk by 68%.

Litvinov says that he struggles to get through to adolescents about the importance of protecting their skin, since many young people want to have tan skin and see themselves as invincible. With them, he uses a different strategy for persuasion.

"Sun exposure will make your skin 10 to 15 years older," he tells them. "If you want blotches and wrinkles, go get the sun."

The aging effect of the sun occurs because UV rays break down collagen and elastin, structural proteins that keep skin firm and elastic.

The best way to avoid harmful sun exposure, he says, is to cover up and seek shade. He recommends wearing clothes made of UV-protective fabrics and hats. For whatever skin is exposed, a thorough layer of sunscreen should be applied and reapplied every two to three hours.

The first commercially available sunscreen came about in the 1920s or '30s, and technology has advanced to make sunscreens more effective at protecting skin from the harmful effects of certain UV rays, according to a 2021 review published in the American Journal of Clinical Dermatology. Some of what experts think are the most effective chemicals, including Tinosorb, Mexoryl, and Uvinul, are used in Europe but have not yet gotten U.S. Food and Drug Administration (FDA) approval, Stanford Medicine News reports.

There are two main types of sunscreen: chemical, which uses ingredients such as avobenzone and octocrylene that absorb the UV rays; and mineral, which physically block the rays. There has been some research linking chemical sunscreen ingredients to endocrine disruption (which affects reproductive hormones) and allergic reactions, though these links were mostly established in lab experiments at very high doses. Chemical sunscreen has also been banned in some places because of its detrimental effects on coral reefs.

Mineral sunscreen can be a good alternative for those worried about chemical ingredients, but they aren't as effective against different kinds of UV rays as the chemical varieties, and they tend to leave a thick, white film on the skin.

While broad-spectrum SPF 50 is recommended, "the best sunscreen is the one you will use," Litvinov says. "My message is to get out, enjoy the outdoors, stay outside, but without getting a tan. No tan is worth dying for."

Progress in treatment

Although skin cancer diagnoses have increased, mortality rates have decreased. Melanoma death in the United States stayed stable from 1992 to 2013, despite the increasing number of cases, and then declined slightly from 2013 to 2023, according to the National Cancer Institute. In 2011 the FDA approved immunotherapy drugs and shortly after gave the go-ahead for several other medications, including BRAF and MEK inhibitors, which slow cancer cell growth.

Even more therapies are in the works. Yu-Ying He, PhD, a professor of medicine at the University of Chicago, spent seven years studying the role of autophagy - the body's self-eating and recycling system - in degrading a key protein, YTHDF2. This protein regulates RNA metabolism and prevents uncontrolled growth and inflammation in skin cells. He published the findings in Nature Communications last November.

"UV affects cellular responses and RNA metabolism, a major pathway UV radiation disrupts," He explains. "We're able to show that when we inhibited YTHDF2, we observed increased inflammation and skin cancer in a mouse model."

This discovery could someday help develop therapies that protect the YTHDF2 protein and control inflammation at the molecular level, to prevent or slow skin cancer.

The discovery is just one of many breakthroughs in the field, including research into genetic mapping of mutations that may lead to cancer; the progress in therapies, including immunotherapy and targeted therapies; and the potential use of AI in diagnosis, He says.

"I think skin cancer research has been experiencing transforming progress," she adds. "Science is making really important contributions."