The sun: Its pros and cons

A healthy level of sunlight is extraordinarily beneficial for both body and mind [Courtesy, Freepik]

You may have heard conflicting advice like "catch the morning or evening sun; it's healthy" and "avoid too much sun to prevent sunburns or skin tumours," leaving you wondering which advice to follow.

Indeed, according to the World Health Organization, exposure to exposure to ultraviolet radiation (UVR), either from the sun or from artificial sources such as sunbeds, can cause skin cancers.

Globally in 2020, over 1.5 million cases of skin cancers were diagnosed and over 120 000 skin cancer-associated deaths were reported. Worldwide, it is also estimated that 15 million people are blind due to cataracts; of these, some 10 per cent may be due to exposure to UVR.

According to dermatologist Dr Kenneth Muthee, a healthy level of sunlight is extraordinarily beneficial for both body and mind.

"Sunlight is important for everyone because it triggers the production of Vitamin D, which enhances bone health. Moreover, it regulates various innate immune system components, making it a key environmental factor in human responses to infection," says Dr Muthee.

Here are some of the sun's positive impacts:

1. Skin's protective barrier: Sunlight prompts keratinocyte differentiation, which is vital for fortifying the skin's protective barrier and sloughing off dead cells, safeguarding against moisture loss and environmental stressors.
2. Wound healing: Moderated sunlight exposure enhances blood flow to wounds, stimulating the production of collagen and filaggrin, proteins essential for skin repair and hydration, respectively.
3. Alleviating skin conditions: Sunlight offers relief for psoriasis, eczema, and neonatal jaundice, while fostering vitamin D synthesis in the skin, it can also help prevent conditions like rickets.

The strength of the sun's ultraviolet (UV) radiation is expressed as a Solar UV Index or Sun Index. Indices of 9 and 10 are common in Nairobi and other parts of Kenya.

Dr Muthee underscores the importance of balanced sun exposure, "Enjoy sunlight in moderation to harness its benefits without risking sunburn, premature ageing, or skin cancer. Safe amounts alleviate a host of problems."