The sun has become something to fear. Across India’s cities, people now move through summer like survivors crossing hostile land, wrapping scarves across faces and rushing between patches of shade as temperatures climb beyond 45°C. This summer, people have fainted in the heat and hospitals have reported deaths caused by heatstroke. The message arriving from television screens, weather alerts and anxious families is relentless: stay away from the sun. And honestly, we have to be terrified. The heat is real. It can kill.
But somewhere inside laboratories, medical journals and long-running scientific debates, researchers are now asking a question that sounds almost dangerous in a country battling deadly heatwaves: what if completely avoiding sunlight is harming us too?
The New Indian Express came across one such major review titled Beneficial health effects of ultraviolet radiation: expert review and conference report. Published in the peer-reviewed journal Photochemical & Photobiological Sciences in 2025, the review was led by researchers including Professor Richard B. Weller from the University of Edinburgh. The review argues that sunlight may be doing far more for the human body than scientists once believed — not just for Vitamin D or bones, but also in lowering risks of heart disease, high blood pressure, type 2 diabetes and some cancers.
Researchers say public health conversations may have become so focused on the dangers of sunlight that they are overlooking its biological benefits. Over the past several years, studies across cardiology, endocrinology and public health research have increasingly linked sensible sunlight exposure with improved cardiovascular health, metabolic regulation and immune function. “But that does not mean people should walk into deadly afternoon heat,” Weller told TNIE.
“We have to understand the difference. Heat is dangerous and heatwaves can cause deaths in the short term. But the benefits of sunlight are different and are long-term effects on health. In simple terms, heat and sunlight are not the same thing.”
Now imagine a young techie in Hyderabad. He leaves for work after sunset and returns home just before sunrise. Curtains stay shut against the blazing heat outside as he sleeps through the day in an air-conditioned room. By evening, he is back under tube lights and the cold blue glare of computer screens at 2 am.
Entire weeks pass without sunlight touching his face. Across Telangana and Maharashtra, thousands now live almost like nocturnal creatures, hiding from daylight so completely that the body may slowly be forgetting what sunlight even feels like.
Scientists say the problem is that modern conversations increasingly treat all sun exposure as equally bad. They argue that this may be too simplistic, especially in a country like India, where sunlight shaped human biology for thousands of years.
To explain why sunlight affects the body so deeply, Weller says we have to travel back tens of thousands of years, all the way to Africa. “Humans arose in Africa in a very sunny place. Your ancestors and my ancestors left Africa about 60,000 years ago. Yours turned right and mine turned left.”
In places with weaker sunlight, such as northern Europe, people gradually developed paler skin to absorb more ultraviolet radiation. In hotter regions like India, darker skin remained because it protected the body from intense sunlight.
Weller believes many anti-sun messages were shaped largely around fair-skinned populations. “The biggest risk factor for sunlight-induced skin cancer is being white,” he said. “If you’re an Indian in India, your skin is adapted to that degree of sunlight.”
The argument remains controversial. Dermatologists continue warning that excessive sun exposure can damage skin, worsen pigmentation and increase risks during extreme weather. But researchers behind the review say the conversation needs more balance than simply telling everyone to avoid sunlight completely.
India today has one of the world’s largest diabetic populations. Cases of high blood pressure, heart disease and metabolic disorders are rising rapidly, especially in cities where people spend most of their lives indoors under artificial light.
According to the review, ultraviolet radiation may trigger the release of nitric oxide — a molecule that helps blood vessels relax and may lower blood pressure. Weller argued that modern medicine may have become too focused on Vitamin D tablets while ignoring sunlight itself. “If sunlight was a drug, pharmaceutical companies would be trying to patent it,” he said, suggesting sunlight receives less attention partly because it is free.
Researchers also believe sunlight may influence the body through multiple pathways, including blood vessels, hormones, sleep cycles and the immune system — effects that Vitamin D supplements alone may not fully reproduce.
Across India, people spend thousands trying to escape the sun. Fairness creams promise “brightening”, anti-tanning clinics advertise “sun damage repair” and sunscreen commercials quietly sell the idea that darker skin is something to fear. Weller believes much of that fear was never designed for countries like India in the first place. “The beauty industry makes money by making people frightened of the sun,” he said. Scientists are not saying people should stand outside at 2 pm during a heatwave. India’s rising heat is real, and it is deadly.
What they are saying is more uncomfortable than that. Modern life has pushed millions indoors — away from playgrounds, fields, streets and sunlight itself. Entire generations now grow up under tube lights, office ceilings and phone screens while fearing the outdoors as something dangerous.
But the human body did not evolve in air-conditioned rooms. And as India’s summers grow harsher every year, the country may eventually be forced to confront a difficult question: in trying to escape extreme heat, are we also cutting ourselves off from something the body still quietly needs?