A Consultant Physician and Dermatologist at the Lagos State University Teaching Hospital (LASUTH) Ikeja, Dr. Folakemi Cole-Adeife has recommended the use of sunscreen to prevent skin cancers, particularly in Caucasians, people with albinism and very light-skinned Africans or Asians.
Explaining how sunscreen could prevent cancer, the consultant physician and dermatologist said this is because the sun’s ultraviolet (UV) rays can cause DNA damage in skin cells which can result in skin cancer.
Cole-Adeife made the call in an interview with the New Telegraph.
However, she noted that sun-induced skin cancer is not common in Africans or people with dark skin, adding, “This is because the extra melanin content in the skin of darker-skinned individuals provides some natural photoprotection from the sun – a form of innate sunscreen.”
Therefore, she reasoned that the use of sunscreen in this category of people is mainly to minimise skin darkening or tanning and to reduce photo-ageing.
Sunscreens are topical products that either absorb or reflect ultraviolet (UV) radiation from the sun when applied to the skin, thus protecting the skin from sunburn or tanning.
Sunscreens can also help to minimise or slow down the development of wrinkles and sagging skin, which is known as photoageing.
Sunscreens can come in different forms e.g. cream, lotion, spray, oil, foam and often also contain moisturizers. Some are also designed to be waterproof.
Chemical sunscreen ingredients are absorbed by the skin into the bloodstream, but physical sunscreen ingredients do not penetrate beyond the outer layer of the skin and are thus not absorbed into the bloodstream. However, there is no evidence that any of these chemicals cause cancer.
According to the dermatologist, sunscreen should be used daily and should be reapplied every three to four hours during the day while there is sunlight. “They do not need to be applied at night,” she added.
Speaking further on the use of sunscreen, she said the product is important to prevent or slow down photo-ageing. For instance, in dark-skinned people, it can be used to minimise tanning and to prevent darkening of the exposed parts of the skin like the face, neck, hands and feet.
However, it is preferable to use a physical blocker sunscreen for this purpose as some chemical-blocker sunscreens can cause darkening of the skin, particularly those with hormone-active ingredients like oxybenzone.
The dermatologist said many people resort to skin bleaching to try and reverse the skin tanning they develop from sun exposure. “They should use sunscreen instead to prevent or minimise sun tanning.
“In so doing they will avoid the harmful effects of skin bleaching which tends to manifest with long term use.”
She however disclosed that some sunscreens can cause skin and eye irritation, adding that everyone should be able to find a sunscreen cream that works for them. “If one has untoward side effects another can be tried,” added Cole-Adeife.
According to her, certain sunscreens have also been found to have a negative impact on the environment, particularly corals, like avobenzone and oxybenzone.
The consultant physician and dermatologist said in Caucasians and people with albinism, the lack of sunscreen use will inevitably result in the development of skin cancer. However, for Africans, Asians and darker-skinned people, lack of sunscreen use permits skin ageing and an increased tendency to skin discolorations and sun-induced skin spots and issues, particularly in people above 40 years. Sunscreen use is important at all ages but more so as one reaches middle age.
Sunscreen use, however, does not preclude sun-induced tanning or burns completely. Thus, it is important to also practice sun avoidance alongside the use of sunscreen creams.
Cole-Adeife said sun avoidance practices include the use of umbrellas for sun protection outdoors during hours of high sun intensity (10 am to 3 pm), avoidance of direct sun exposure during these hours, wearing protective clothing on hot days and the use of hats and sunglasses to protect sun-exposed areas like the head and neck. She added, “Sunscreen use should be combined with sun avoidance practices for optimal sun protection.”
She noted that sunscreens have different strengths, what is commonly referred to as the sun protection factor (SPF). SPF refers to the degree to which a sunscreen can block ultraviolet B (UVB) rays, which can cause sunburns. The SPF in sunscreens ranges from SPF 10 to up to 100.
Cole-Adeife said, “For tropical climates like ours in Nigeria, there is higher UV intensity from the sun, and it is recommended that a sunscreen with SPF 30 and above is used, preferably SPF 50.
“In temperate climes like Northern Europe and some parts of North America for example, an SPF 15-20 sunscreen may be sufficient.”
However, she said no matter the SPF factor of the sunscreen, it must be reapplied regularly to be effective. According to her, it is also important to use a broad-spectrum sunscreen that has protection against both UVA and UVB rays from the sun. Sunscreens with only UVB protection may not be as effective in protecting against photo ageing and certain skin cancers.