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Expert claims that sun exposure not the cause of melanoma

Sun exposure is not the cause of malignant melanoma, and we should "strike a balance" between avoiding too much sun and getting the beneficial health effects of sunlight, a consultant dermatologist has argued.

However, in response, a professor from the Sydney Melanoma Diagnostic Centre argues that melanoma is indeed more common on body sites receiving more sun exposure.

On the BMJ website, dermatologist Sam Shuster says that sun exposure is the major cause of the common forms of skin cancer, which are all virtually benign, but not the rarer, truly malignant melanoma.

Dr Shuster says melanoma is related to ethnicity rather than pigmentation, and in 75% of cases occurs on relatively unexposed sites.

He even says that melanoma occurrence decreases with greater sun exposure and can be increased by sunscreens, while sun bed exposure has a small inconsistent effect.

Therefore, he concludes, any causative effect of ultraviolet light on melanoma can only be minimal.

While he recognises that ultraviolet light causes the common, mainly benign, skin cancers and wrinkles the skin, he says this is not a good enough reason for a blanket ban and we have to strike a balance with the sun's many other effects on health — from psychological and immunological, to the synthesis of vitamin D essential for bones and apparent protection against many major organ cancers.

However, Professor Scott Menzies, from the University of Sydney at the Sydney Melanoma Diagnostic Centre, says there is considerable evidence that intermittent sun exposure and sunburn are strong independent indicators of the risk of developing melanoma in white populations.

He argues that there is a clear association between increasing cases of melanoma and increasing environmental ultraviolet light.

He points to data from Australia showing that cases of melanoma among young adults fell between 1983 and 1996, which coincided with strong public health messages to use sun protection.

When you examine the geographical, sun exposure and genetic evidence together, sun exposure is clearly a major cause of melanoma, he concludes.


Your comments: (Terms and conditions apply)

"Yes. A lack of moderate sun exposure and overzealous usage of sunscreen can block vitamin D3 absorbing into the body, which is essential in the balance of everyday health. Without the sun, we wouldn't exist. Known fact! As for myself, I've been working in the tanning industry for almost four years now, have been educated through Smart Tan, and recently had an aunt pass away on Christmas due to complications from skin cancer. She
also wore sunscreen everyday. I've always believed in truthfully educating the public on indoor/outdoor moderation of UV exposure and proper skin care. Scaring people into running from something that's natural and is the purpose of our existence is only going to create more health problems worldwide. Tanning is your body's natural response in protecting the skin against over exposure. But, if are unable to tan (skin type 1/ without p53
genome to produce melanin) then you should definitely cover up everyday because you'll be at risk. People need to understand that tanning isn't the absolute cause of skin cancer,  it's genetics and overexposure" - Tammie, Los Angeles, USA

"I have lost two close friends in the last two months. Both had incidents of severe cases of sunburn. Let's try and tell the grieving families of these two lovely young lads, 28 and 30, that the sun doesn't cause this illness" - Gillian Nuttall, UK