By Staff Reporter
NAIROBI, Kenya — As millions of people across Africa go about their daily routines under intense sunlight, health experts are warning that the biggest danger may not always be the heat people can feel, but the ultraviolet (UV) radiation they cannot see.
UV exposure can occur during ordinary activities such as commuting, walking, working outdoors or sitting near a window. Over time, repeated exposure can damage the skin and eyes and increase the risk of serious health conditions, even when temperatures are moderate.
The warning comes as health experts encourage the public to make sun protection part of their everyday routines rather than treating it as something reserved for holidays, beaches or particularly hot days.
Across Africa, UV exposure varies depending on factors such as location, altitude, season, cloud cover and time of day. In addition, surfaces such as sand, water and concrete can reflect UV radiation, increasing the amount that reaches the skin.
The World Health Organization (WHO) classifies a UV Index of 11 or above as “extreme” and recommends sun protection whenever the index reaches 3 or higher.
Although people with darker skin generally have more melanin, which offers some natural protection against UV radiation, this does not make them immune to sun-related damage.
The WHO has linked excessive UV exposure to skin cancer, cataracts and damage to the immune system, while the International Agency for Research on Cancer classifies solar UV radiation as a Group 1 carcinogen.
Daily exposure can have long-term effects
Dr. Paula Fakhre, a cosmetic dermatologist and graduate of St. George’s University, said one of the biggest misconceptions about sun protection is that people only need it when spending extended periods outdoors.
“People think sun protection is for the beach, but UV exposure is something we live with every single day,” she said.
Dr. Fakhre noted that short periods of exposure can accumulate over time, whether someone is driving to work, walking between buildings or sitting close to a window.
Unlike UVB, which is largely responsible for sunburn, UVA radiation can penetrate window glass and reach deeper layers of the skin without causing immediate pain.
“By the time you notice wrinkles or dark spots, the damage has already happened,” she said.
She urged consumers to choose a broad-spectrum sunscreen that suits their skin type, apply enough of the product and reapply it regularly.
“These small habits reduce long-term risk significantly,” she added.
Not all UV radiation is the same
Understanding the different types of UV radiation is important when choosing appropriate protection.
The sun produces UVA, UVB and UVC radiation. However, each type affects the body differently.
UVC has the shortest wavelength and carries the highest energy, but the ozone layer absorbs nearly all of it before it reaches the Earth’s surface.
UVB, meanwhile, affects the outer layer of the skin and is the main cause of sunburn. It can damage DNA in skin cells and trigger increased melanin production. Prolonged exposure also contributes significantly to non-melanoma skin cancers such as basal cell carcinoma and squamous cell carcinoma.
UVA penetrates deeper into the skin, reaching the dermis where collagen and elastin fibres are found. Repeated exposure can generate reactive oxygen species that contribute to collagen breakdown, premature ageing and wrinkles.
More importantly, UVA can pass through window glass, meaning people who spend considerable time driving or working near windows may continue accumulating exposure without experiencing sunburn.
UVA makes up roughly 95 per cent of the UV radiation that reaches the Earth’s surface and is also associated with immune suppression and skin damage, including melanoma.
Sunscreen or sunblock?
Consumers may also encounter the terms “sunscreen” and “sunblock” when shopping for sun protection products.
Chemical sunscreens contain organic filters such as avobenzone, oxybenzone and octinoxate. These compounds absorb UV radiation and convert it into heat, which is then released from the skin.
Because they tend to be lightweight and blend easily into the skin, chemical formulas are commonly used for everyday protection.
Mineral or physical sunblocks, on the other hand, contain filters such as zinc oxide and titanium dioxide. These ingredients remain on the surface of the skin and help reflect and scatter UV radiation.
Zinc oxide provides protection across both UVA and UVB wavelengths, while titanium dioxide offers strong UVB protection and protection against shorter UVA wavelengths.
For people with sensitive skin, mineral formulations may be preferable because they generally remain on the skin’s surface. However, some can leave a visible white cast, although newer micronised formulations have reduced the problem.
Hybrid products combining chemical and mineral filters are also increasingly available and can offer broad-spectrum protection in formulations designed for easier everyday use.
SPF does not tell the whole story
One of the most misunderstood aspects of sunscreen is the SPF number displayed on the label.
SPF stands for Sun Protection Factor and primarily measures protection against UVB radiation. It does not measure UVA protection.
An SPF 30 product blocks approximately 97 per cent of UVB radiation under standard testing conditions, while SPF 50 blocks about 98 per cent.
However, the actual level of protection a person receives depends largely on how much sunscreen is applied.
SPF testing assumes an application rate of approximately 2 milligrams per square centimetre of skin. Since many people use considerably less, they may receive significantly less protection than the SPF number suggests.
For the face and neck, the two-finger method is commonly used to estimate an adequate amount. Protecting the entire body can require approximately 30–35 millilitres of product.
Look beyond the SPF number
Because SPF only indicates UVB protection, consumers are advised to look for broad-spectrum products that also provide UVA protection.
This is particularly important in African markets, where products from different regulatory systems are widely available.
Consumers should check labels for “broad spectrum” and, where applicable, a UVA protection seal or PA rating. The PA system, widely used in parts of Asia, ranges from PA+ to PA++++, with additional plus signs indicating stronger UVA protection.
At the same time, sunscreen should not be viewed as a one-time application.
Sunlight can degrade some chemical filters, while sweat, swimming, clothing and towel drying can remove sunscreen from the skin. Regular reapplication is therefore essential.
No sunscreen should be considered completely waterproof.
Making sun protection an everyday habit
With UV Awareness Month drawing attention to the risks associated with excessive exposure, health experts are encouraging people across Africa to pay attention to UV levels rather than relying solely on how hot the weather feels.
Using broad-spectrum sunscreen correctly, reapplying it when necessary, wearing protective clothing and hats, seeking shade and limiting exposure during periods of intense UV radiation can all help reduce the risk of long-term damage.
Ultimately, effective sun protection begins with understanding that UV radiation is present even when the heat does not feel extreme.
For communities across Africa, making sun safety part of everyday life could help reduce preventable skin and eye conditions while allowing people to continue enjoying outdoor activities more safely.
