A Finnish study of nearly 500 people who had an increased risk of skin cancer revealed fewer cases of melanoma in those who took vitamin D supplements regularly. These people also had an estimated lower risk of developing other forms of skin cancer.
In the study from the North Savo Skin Cancer Programme, 498 adults (aged 21 to 79 years, 253 males, 245 females, 96 with immunosuppression) at risk of any type of skin cancer (basal cell carcinoma, squamous cell carcinoma or melanoma) were assessed. They were divided into three groups based on their self-reported use of oral vitamin D supplements: non-use, occasional use, or regular use. The study, conducted in collaboration between the University of Eastern Finland and Kuopio University Hospital, was published in Melanoma Research.
Participants were recruited at the dermatologic outpatient clinic of Kuopio University Hospital, and dermatologists at the University of Eastern Finland reviewed the patients’ background information and medical history and examined their skin. The patients were classified into skin cancer risk classes: low risk, moderate risk, and high risk. Serum calcidiol levels, a metabolite of vitamin D, were analyzed in 260 patients and found to correspond to their self-reported use of vitamin D.
Logistic regression analysis showed that the risk for melanoma among regular vitamin D users was more than halved compared to non-users (odds ratio 0.447, p= 0.016, 95% confidence interval, 0.231–0.862). The estimated risk class of all skin cancers was significantly lower among regular users of vitamin D, the researchers reported.
Finnish researchers previously reported (BMC Cancer 2021) that the melanoma mortality rate in North Savo is relatively high in relation to its incidence, according to a press release.
“These earlier studies back our new findings from the North Savo region here in Finland.
However, the question about the optimal dose of oral vitamin D in order for it to have beneficial effects remains to be answered. Until we know more, national intake recommendations should be followed,” Professor of Dermatology and Allergology Ilkka Harvima of the University of Eastern Finland noted in the release.
In Finland, vitamin D recommendations are 10 µg/d (six months to 74 years), and 20 µg/d for those 75 years and older.