The next time you’re out in the sun and worrying about getting dark, remember: The very pigment or melanin that gives us our unique skin tone is what’s offering us protection.
“Simply put, melanin is the skin’s natural defence against UV rays,” said Dr Calvin Chan, the medical director of Calvin Chan Aesthetic & Laser Clinic. “Melanin helps to dissipate some UV light into heat, thus blocking UV radiation from reaching and damaging skin’s DNA.”
Of course, we know that excessive UV radiation isn’t good for us. It’s a precursor to DNA damage, which as Dr Chan explained, can lead to cancer-causing mutations in the skin.
Yet, skin cancer prevention doesn’t always top our list when it comes to skincare. Some of us are also under the impression that we are less likely to develop skin cancer because of said built-in personal sunblock. After all, most skin cancer reports are usually about fair-skinned folks from the other side of the world, right?
In a sense, it’s true. Caucasians are more prone to skin cancer than Asians, according to the International Agency for Research on Cancer’s GLOBOCAN statistics for 2018.
When you compare the incidence rates (for melanoma and non-melanoma skin cancers) in predominantly Caucasian countries such as Australia, New Zealand and Norway – which are also countries with the highest skin cancer cases in the world – Singapore’s rate is low.
- Australia - 181.1 per 100,000
- New Zealand - 171.7 per 100,000
- Norway - 44.8 per 100,000
- Singapore - 3.9 per 100,000
But it’d be erroneous to think we don’t have to worry about skin cancer at all.
“Skin cancer is one of the top 10 most frequent cancers in Singapore, representing the sixth most common cancer in males and seventh in females,” said Clinical Assistant Professor Jason Chan, a consultant with National Cancer Centre Singapore’s Division of Medical Oncology.
DOES SKIN COLOUR REALLY DETERMINE SKIN CANCER RISK?
Among Asians, the fairer you are, the higher your risk of skin cancer, said Dr Aaron Tan, a consultant with National Skin Centre, referencing a 2009 study in the Journal of the American Academy of Dermatology.
“It analysed skin cancer data from the Singapore Cancer Registry from 1968 to 2006, and concluded that skin cancer rates among the fairer-skinned Chinese were approximately three times higher than in Malays and Indians, who generally have darker complexions.”
Skin cancer is one of the top 10 most frequent cancers in Singapore, representing the sixth most common cancer in males and seventh in females.
However, Dr Chan cautioned against using skin tone as a gauge of one’s skin cancer risk. “Everyone is at risk as long as he or she experiences UV exposure. It might give a false sense of security to say that if you are Asian, you are X per cent less likely to get skin cancer."
He continued: "It is not advisable to say how much more or less likely one is to get skin cancer based on skin colour alone. There are simply too many factors involved, such as genetics, hormones, environmental exposures, age and gender".
Citing the National Center for Biotechnology Information in the US, Dr Chan explained that when individuals with darker skin develop skin cancer, the early-stage lesions are often missed as they are “brown and may be less obvious”.
These patients often have a worse prognosis as their cancer is only detected at an advanced stage.
“This is another reason why no matter one’s skin colour, everyone must practise sun safety and always be protected from UV radiation,” he said.
It is not advisable to say how much more or less likely one is to get skin cancer based on skin colour alone. There are simply too many factors involved, such as genetics, hormones, environmental exposures, age and gender.
WHAT KIND OF SKIN CANCERS ARE ASIANS PRONE TO?
Skin cancers are classified as melanomas and non-melanoma types, said Clinical Asst Prof Chan. “Non-melanomas generally consist of basal cell carcinomas and squamous cell carcinoma. Other rare subtypes include sarcomas and lymphomas of the skin, Merkel cell carcinoma and sebaceous gland carcinoma.”
READ: What’s that thing on your nose? How to stay on guard against skin cancer
Non-melanoma skin cancers are commonly caused by chronic sun exposure, so the areas that are prone include the scalp, forehead, nose, neck and back of the hands. Melanomas, though rare in Asians, tend to develop into “a unique subset of melanoma”, said Clinical Asst Prof Chan.
“This is known as acral lentiginous melanoma and is the most common subtype of melanoma in Singapore.” They tend to be found, ironically, in sun-protected areas, such as over the palms of the hands, soles of the feet, and under the nails.
Despite their rarity, Clinical Asst Prof Chan said that melanomas are the most dangerous form of skin cancers. They can be aggressive and have a tendency to metastasise, which account for the majority of all skin cancer deaths, he said.
AREN’T MASKS AND MAKEUP WITH SPF ENOUGH?
You might be wondering: Now that we have to wear masks when we go out, can we skip sunblock for the face? After all, the typical mask – whether disposable or cloth – has a few layers of material to block out UV, right?
Like SPF for sunblock, the UV protection from a fabric is also measurable but in UPF. "A UPF rating of 50 indicates the fabric will allow 1/50th – or about 2 per cent – of the ultraviolet radiation from the sun to pass through to your skin," said Dr Chan. "The higher the UPF number, the less light and UV radiation reach your skin."
The Skin Cancer Foundation in the US recommends UPF 30 or higher for adequate sun protection, said Dr Chan. But if your mask has no UPF indication, "a good gauge would be to hold your mask up to the sunlight. The less light gets through, the less stretchy it is and the darker its colour, the better its UV protection."
The same gauge goes for clothes, too. And if you're not too covered up (for instance, you have a tank top and berms, or spaghetti-strapped top with denim shorts on), it's a good idea to protect the exposed areas such as your neck, shoulders, arms and legs with a sunblock of at least SPF 30, regardless of skin tone, advised Dr Tan.
As for skincare or makeup products with SPF, don’t they count? “I believe that sun protection has a separate and distinctly different function from other skincare and makeup products,” said Dr Chan. “Sun protection should be regarded as a crucial last layer in your skincare routine, applied to form a protective film to shield skin from UV rays.”
So even if you have a layer of moisturiser or makeup with SPF, the best thing is still to apply an adequate layer of sunscreen for sun protection, he said.
Also, don’t slap sunscreen on in the morning and leave it at that. To attain the level of SPF protection stated on the bottle, you must reapply at two- to four-hour intervals, said Dr Chan. And not just that, you have to use an adequate amount, which according to Dr Tan, is 2mg per sq cm. As a gauge, that’s about one quarter teaspoon for just the face.