Unlike America's recommendations, Australian authorities don't encourage routine sunscreen use for darker skin tones—reasoning that melanoma risk is low, and it's better to get UV exposure to help the body naturally produce vitamin D.

Demystifying sunscreen

Sunscreen is helpful all year round. Experts argue a minimum level of protection is SPF 30. There are two kinds of sunscreen: mineral (a physical barrier) and chemical (absorbs UV light). No new sunscreen ingredients have been approved in the US in decades, so foreign products are common.

Mineral and chemical sunscreens protect differently, but both guard against UV damage.

'Barbie' drug melanotan II purportedly offers tanning without the sun—but it's very risky

The substance is not approved by the FDA and is illegal to sell in settings including the UK and Australia. Published case reports discuss serious side effects, including melanoma, a type of skin cancer.

This 1440 Original video dives into what the science says about phototherapy and its various potential applications.

Learn why the Montreal Protocol may help prevent millions of cancer deaths

By restoring the ozone layer and reducing ultraviolet exposure, full implementation of the Montreal Protocol is expected to prevent about 443 million cases of skin cancer, 2.3 million skin cancer deaths, and 63 million cases of cataracts among Americans born from 1890 to 2100.

Why Earth would become a more deadly environment without the ozone layer

The ozone layer blocks almost all of the sun's harmful, including dangerous UVC rays that can damage cells by breaking chemical bonds. Without it, rates of skin cancer, crop failures, oceanic die-offs, and widespread ecosystem collapse would increase significantly, making Earth largely uninhabitable.

When diving and snorkeling in environments containing reefs, avoid touching reefs, anchoring on them, or using sunscreen with active ingredients harmful to marine life.

Cold-blooded reptiles seek heat, and that behavior may help combat fungal infections

This Radiolab podcast episode takes on the idea that though our human bodies are too warm for the majority of fungal species to effectively replicate inside our bodies, that's not the case for reptiles. Yet when those species warm their bodies by basking in the sun on rocks, they can soak up heat and may also help keep fungal infections in check.

Vitamin D supplement pills are linked to rising cases of vitamin D toxicity in the US

Vitamin D deficiency is common. But taking Vitamin D supplements in doses exceeding 4,000 IU/day (a measurement of vitamin biological activity) for prolonged periods can raise bodily concentrations of this vitamin to dangerous values. US National Poison Data indicates that the annual average of vitamin D poisonings from 2000-05 was 196, but this rose by 1,600% to 4,535 per year for the period of 2005-11.

Red light therapy—a treatment harnessing a specific form of energy that penetrates the top layers of skin—is marketed for skincare and wellness, but has its roots in NASA plant growth research.

The UV index measures the sun's ultraviolet radiation risk on a scale of 1 to 11+

The tool takes into account geographical location, time, elevation, and cloud coverage to help individuals plan their daily activities around the sun's peak UV exposure times, which occur from 10:00 am to 4:00 pm. A value at or above 6 requires sunscreen (SPF 15+), shelter, or UPF clothing

Most adults don't need a daily vitamin, and it won't extend your life

A 20-year study by the National Cancer Institute involving almost 400,000 people found that daily multivitamins did not help people live longer. In some cases, these vitamins also increased the risk of death. Although some subpopulations—such as those with documented vitamin deficiencies and pregnant individuals—should take vitamins, daily multivitamins should not be taken uniformly by adults. Instead, patients should discuss vitamins with their clinicians and consider baseline vitamin testing before starting vitamin regimens.

Lack of Vitamin D seems to be one major factor fueling MS risk

Researchers believe that a combination of factors can elevate MS risk, including a lack of vitamin D exposure in different locales, genetic history, cigarette smoke exposure, and Epstein-Barr virus infection.

Protecting astronauts against space radiation

Outside the protective atmosphere of Earth, astronauts are constantly bombarded by radiation, which, among other dangers, increases the risk cancer. While those of us on Earth can mitigate the effects of similar radiation by limiting exposure,...

Some corals absorb harmful ultraviolet radiation and re-emit it as visible light, thereby protecting symbiotic algae within their tissues and providing them with energy for photosynthesis.

MS risk is shaped by geography, not just genes

Latitude—and related vitamin D exposure—seems to affect MS risk. People who migrate from a high-risk MS latitude (like northern Europe or the northern US) to a lower-risk latitude (like tropical areas) before age 15 tend to adopt the lower risk of their new country—suggesting there's a critical window for environmental exposure.

The lack of diversity in clinical trials is undermining the future of precision medicine

Medicine works better when the treatments are tailored to fit each individual person’s biology and history. Homogeneous patient selection in clinical trials means treatments and care are being refined based on only a small range of variables, some of which may not apply to you. This 40-minute podcast episode discusses the historical and current reasons for the lack of clinical trial diversity and what this means for the future of personalized medicine.

Starting with red, colorful objects will appear to lose their colors the deeper they are submerged because water scatters light, reducing the amount available to reflect off objects and be observed.

Synthetic pheromones may protect coral reefs by attracting their predators

Researchers in Australia and Japan have developed these nontoxic chemicals to attract crown-of-thorns starfish, which consume corals that make up the Great Barrier Reef. As of 2026, synthetic pheromones have been shown to be effective in lab trials, and future field trials will attempt to lure starfish into areas for mass removal.

In 2026, the US FDA approved a light-activated gel combined with red light therapy as a nonsurgical treatment option for the most common type of skin cancer.

Do you need a multivitamin?

In 2013, several researchers declared multivitamins dead, stating that so-called supplements had no clear benefits and might be harmful. But the science isn't so clear-cut. This article explores the question of who would benefit from...

Misleading measurements and fear-based reporting often exaggerate radiation risks

Daily exposure to radioactivity is common but occurs in low doses outside of locations near nuclear accidents like Chernobyl and Fukushima. Researchers have detected radiation in tuna, bananas, and the human body due to increasing instrumental sensitivity, not rising concentrations.

From glands beneath their skin, hippos produce their own sunscreen in the form of a fluid containing hipposudoric and norhipposudoric acids, which absorb sunlight in the ultraviolet and visible range.

Because the retina lacks pain receptors, during a solar eclipse, those watching without protective eyewear may suffer from permanent damage without realizing it.

There is a template for how to live a better, healthier day, and it includes a digital sunset

Science suggests that early-morning exercise, later-morning peak work or social time, consistent exercise, and a "digital sunset"—starting to turn down the lights in the evening and avoid screens—are important for circadian health.

Eclipse glasses protect the eyes from overexposure to the sun's ultraviolet, blue, and infrared light, as a person's instinct to look away from the sun is diminished when it's partly blocked.

Inside Australia's National Sea Simulator, scientists are cross-breeding coral species and using CRISPR to genetically engineer heat-resistant corals to withstand warming reefs worldwide.

High-powered red light therapy—delivered directly to nerve fibers via a fiber optic needle—has been used in recent experimental research to suppress pain.

How race science influences breast cancer research

Despite researchers' and physicians' pushback, race is still used in studies and clinics to categorize human differences in health conditions and treatment responses. This article explores how race has influenced breast cancer research. Considering race as a factor in cancer research, diagnosis, and treatment can lead to racial inequalities. Sociocultural factors, including food access and air pollution, greatly influence health outcomes.

Supplements are only typically recommended for those with a proven deficiency

Blood tests and other dietary screening tools by clinicians and nutritionists can indicate whether someone is deficient in needed vitamins or minerals, and those results can then lead to a personalized care plan that may include supplements. Supplements can negatively interact with certain medications, so it's important to speak with your doctor about supplements before taking them.

American Psychological Association issues recommendations for teen social media use

Listen to this three-minute podcast to learn more about the American Psychological Association's recommendations for teenagers' use of social media. The first report of its kind, it advises parents to closely monitor teens' social feeds during early adolescence, continually screen for signs of problematic use (such as sleep interference), minimize the amount of dangerous content their child is exposed to (such as disordered eating), and limit their teen's use of social media around appearance-related content.

Listen to a reporter discuss his story spotlighting a decadeslong corporate cover-up about forever chemicals, substances, which can persist in the environment for hundreds of years—though not forever.

Hear firsthand how scientists and policymakers saved the ozone layer

In this episode, atmospheric chemist Susan Solomon and Protocol architect Stephen Andersen recount how scientific discovery, diplomacy, and public pressure drove the Montreal Protocol—and share lessons for tackling climate change.

Can we speed up our metabolisms?

Listen to this 31-minute podcast to better understand what science knows and doesn't know about metabolism, as well as the only thing that seems capable of changing it. Scientists understand that the difference between a so-called “fast” and “slow” metabolism does not affect one’s ability to lose weight.

Microplastics 101: What we know about the contaminants invading our bodies

Fifty-one trillion particles of microplastics float in our oceans. Yet there is very little science of how this affects our health. This quick 2-minute video explains the dangers of microplastics.

Ozone protects against the sun's UV radiation and enhances the greenhouse effect

In the stratosphere, trioxygen molecules can absorb harmful ultraviolet radiation from the sun, preventing it from reaching Earth's surface, where it can harm organisms and raise surface temperatures. In the lower atmosphere, ozone acts as a greenhouse gas, trapping thermal radiation.

Extreme heat puts people at risk of developing kidney stones

It's essential to remain hydrated in summer weather to keep your body healthy, but one reason is to help dilute minerals that naturally build up if they aren't excreted in our water-fueled urine. Doctors recommend people generally drink 64 ounces of water a day and also eat foods with salt to help ward off dehydration.

10 percent of SAD cases occur in the summer

Despite its significantly lower incidence, summer-risk SAD is as significant as its winter counterpart. Rather than being prompted by less light, the summer version is typically spurred by high temperatures, strong light, distinct summer time social pressures (appearing in a bathing suit, for example), and pollen. Common treatments include keeping cool and prioritizing sleep.

Strengthening your butt muscles can help protect against running injuries

More than 28 million people may go running in the US every week, yet people often get hurt—especially with knee injuries—and this podcast explores the science on what happens to our bodies when we run and the effects on our muscles and joints. It also discusses safety tips, including the need to only add more distance to your runs in tiny increments, and that strengthening glute muscles via single-leg glute bridges may be particularly protective against injuries.

Dietary supplements are regulated like foods

This hour-long 2016 documentary from Frontline, the Canadian Broadcasting Corporation, and The New York Times examined the safety of dietary supplements. It noted that this then-$30B industry (it's at least doubled since then) suffers from irregularities and impurities. It warned that many Americans are unaware of the lack of regulatory oversight over these products.

This 'Science Vs' episode checks the taste, health, and environmental claims about organic food against the actual research.

Understanding why charged particles from the sun protect Earth from more dangerous particles

The solar wind engulfs the solar system in a protective bubble called the heliosphere, which was first theorized in the late 1950s based on studies of cosmic rays—high-energy particles traveling through space at near light speed. The heliosphere shields the solar system from much of this ionizing radiation originating elsewhere in the Milky Way.

Forever chemicals are so common that experts concluded in 2022 that it's uncertain whether limiting consumer exposure would truly reduce one's exposure to these substances, and noted it would still take years for the body to clear them.

Genetic tests aren't always actionable, which is one reason genetic counselors are so vital

This podcast interview with a Harvard Medical School professor focused on cancer genetics and prevention discusses the specifics of genetic testing and insights and the challenges of processing the outcomes of the testing and what may be actionable—or not.

During coral bleaching, corals sacrifice their food source and expel colorful microorganisms to protect themselves, a phenomenon that resembles an organism's immune system attacking itself.

About 10% of the radiation people are exposed to each year comes from outer space, with higher percentages for those living at higher elevations or who fly often.

Humans need vitamins, but research is mixed on taking supplements

When an organism needs an organic molecule to survive, but cannot synthesize enough of it itself, that molecule is called a vitamin. Typically, we consume vitamins through food, but many resort to supplements—a common and mostly unregulated practice.

Remember: Not all fats are bad for you

Contrary to past dietary advice promoting low-fat diets, newer research shows that certain types of fats are both necessary and healthy. It all comes down to the type of fat you eat. Focus on getting "good" unsaturated fats from sources like nuts,...

About 40% of cancer cases are linked to preventable risk factors

Maintaining a healthy weight, engaging in regular physical activity, and consuming a balanced diet can lower cancer risk. Research indicates that about 40% of US cancer cases are linked to preventable factors, including poor diet and inactivity. Understanding these mechanisms empowers individuals to adopt healthier lifestyles for cancer prevention.

As immobile animals, corals and the organisms that live on them have evolved a suite of chemical compounds to prevent disease and ward off predators they cannot outrun.