By Dr Ananya Mandal, MD
A study has shown that a daily vitamin pill could help prevent skin cancer - particularly among women. Scientists say taking food supplements containing vitamin A can make people less likely to develop melanoma, the deadliest form of the disease.
A study found that retinol - a key component of Vitamin A - could protect against the illness. Retinol belongs to a class of compounds called retinoids that have been shown to stop cells dividing and spreading. The strongest protective effects were found in women and in sun exposed sites, suggesting retinol actually combats skin cancer. However, there was no association between dietary intake of vitamin A, found in liver, eggs and milk, and a reduction in risk.
In addition there was also no reduced risk seen by the intake of carotenoids, which are abundant in vegetables including carrots and tomatoes and absorb compounds that can damage the skin. Previous research with mice has shown retinol and carotenoids can shrink melanoma tumours and improve survival. Retinol is also good for the immune system and eyesight
Dermatologist Dr Maryam Asgari and colleagues analysed the disease risk in 69,635 men and women aged between 50 and 76 who consumed vitamin A through either dietary or supplementary methods. Their study is published in the Journal of Investigative Dermatology.
It showed that those who used retinol regularly were 60 per cent less likely to develop skin cancer, rising to 74 per cent among participants on the highest doses of more than 1,200 mg a day.
Dr Asgari, of the Kaiser Permanente Northern California Division of Research in Oakland, said, “Our data suggest a possible interaction between supplemental retinol use and the anatomic site of melanoma, with sun-exposed sites showing a stronger protective effect than sun-protected sites. It may be that retinol's effects may be mediated by sunlight exposure. This intriguing possibility warrants further exploration in future studies.”
“It was definitely linked with supplements, not diet,” says Asgari. She points out that the effects were only seen in people who were taking more vitamin A than what is found in multivitamins.
Dr Asgari said, “In summary, our data, which are based on a large prospective cohort, suggest retinol intake from individual supplements is associated with a reduction in risk for melanoma, especially among women. Our findings suggest vitamin A supplementation may hold promise as a chemopreventive agent for melanoma.” “People who are concerned about melanoma should avoid sun exposure, practice sun protection, and get annual skin checks,” she added.