The Health Benefits of Sunlight and the Systematic Attempt to Discredit It

Tejasvani Knowledge Desk

In the Indian tradition, the Sun has always been revered as a source of life and energy, and for good reason. Sunlight, together with the Earth’s natural grounding or earthing, remains one of nature’s greatest gifts for human health.

Somewhere in the last century, “sun-kissed” bodies became a fashion statement. Excessive exposure led to skin damage, and skin cancers were strongly associated with ultraviolet radiation. This created the perfect environment for the rapid expansion of the sunscreen and cosmetics industry. Gradually, the idea was promoted that sunlight itself was dangerous and should be avoided, blocked, or neutralized.

This narrative, however, does not reflect biological reality, especially in a country like India.

Sunlight, UV Radiation, and the Indian Context

Based on the Global Assessment of Surface Ultraviolet Radiation and Malignant Skin Melanoma Incidence from 1990 to 2021, India is among the least affected regions in the world when it comes to UV-related skin cancers.

Globally, about 83 percent of melanoma cases are linked to UV exposure. The burden is highest in lighter-skinned populations, older age groups, and regions with lower natural sun exposure. India’s incidence is less than 0.01 per 100,000 population, with most cases observed among elderly rural laborers who work long hours under direct sunlight.

Brown and black skin types naturally possess four to seven times greater tolerance to solar radiation. This is an evolutionary adaptation. Darker skin evolved in high-heat regions, while lighter skin adapted to colder climates. Even within India, higher melanoma incidence is seen mainly in relatively fair-skinned populations of North and North-East India and predominantly among older individuals with occupational exposure.

For the majority of Indians, excessive fear of sunlight is unnecessary.

What Sunlight Contains

Approximately 50 percent of sunlight reaching the Earth is visible light. Around 45 percent is infrared radiation. Only about 5 percent consists of ultraviolet radiation, including UVA and UVB.

Of this ultraviolet component, roughly 95 percent is UVA and only 5 percent is UVB. Although UV radiation forms a small fraction of sunlight, it is biologically very active and essential for many physiological processes.

Understanding the UV Index

The UV Index was developed by the World Health Organization and other international scientific bodies to communicate the potential risk of sun exposure. It is a linear scale where higher values indicate greater risk of sunburn due to UVB exposure.

An index of zero corresponds to nighttime conditions. An index of twelve corresponds roughly to a clear midday summer sun in Mediterranean regions. Doubling the UV Index roughly halves the time required to cause sunburn, but this does not imply that sunlight should be completely avoided.

The Fitzpatrick Skin Scale

Developed in 1975, the Fitzpatrick Skin Scale remains the gold standard for estimating how different skin types respond to ultraviolet radiation. Most Indians fall into skin types that are naturally well adapted to regular sun exposure.

Positive Effects of Sunlight on Human Health

Vitamin D

Vitamin D influences cancer risk, cardiovascular health, diabetes, depression, multiple sclerosis, and immune regulation. The primary and natural source of vitamin D is UVB exposure from sunlight. It is estimated that 80 to 90 percent of daily vitamin D requirements are met through sun exposure.

Sun-derived vitamin D is self-regulated by the body, preventing toxicity, unlike excessive supplementation.

Cardiovascular Health

Sun exposure triggers the release of nitric oxide from the skin into the bloodstream. Nitric oxide dilates blood vessels, improves circulation, reduces blood pressure, and helps prevent arterial stiffness.

For every person who dies from skin cancer, more than one hundred people die from cardiovascular disease. Low vitamin D levels are consistently associated with higher cardiovascular risk.

Immune System Modulation

Ultraviolet radiation has potent immunomodulatory effects. It influences both innate and adaptive immunity and affects the outcomes of inflammatory, autoimmune, infectious, and malignant diseases.

Bone Health

Vitamin D deficiency leads to impaired calcium absorption, resulting in osteomalacia and osteoporosis. Globally, one in three women and one in five men over the age of fifty are at risk of osteoporotic fractures. As vitamin D synthesis decreases with age, regular sun exposure becomes increasingly important.

Sunlight and Cancer Protection

Moderate sun exposure has been associated with reduced risk and improved outcomes in several cancers, including breast, colorectal, prostate, lung cancer, leukemia, and non-Hodgkin lymphoma. Many of these protective effects cannot be explained by vitamin D alone, suggesting additional sunlight-dependent biological pathways.

Sunlight and Chronic Diseases

Adequate sun exposure has shown benefits in autoimmune diseases, type 2 diabetes, multiple sclerosis, respiratory infections, Alzheimer’s disease, depression, pregnancy outcomes, and inflammatory bowel disease.

Should We Fear the Sun?

No. Chronic sun avoidance may be far more harmful than sensible sun exposure. The real issue is not sunlight itself, but excess, imbalance, and misinformation.

Regular and moderate sun exposure, adapted to skin type, geography, and lifestyle, is one of the simplest and most powerful tools for maintaining health.

Final Thought

The Sun is not our enemy. It never was. Re-establishing a balanced relationship with sunlight may be one of the most natural ways to restore and preserve health.