Fewer moles, lower melanoma risk

Children today are developing fewer moles than kids 25 years ago

One of the central aims of the Brisbane Longitudinal Twin Study (BLTS) has been to investigate the genetic and environmental contributions to melanoma risk factors. Now, after decades of research, the findings are encouraging: children today are developing significantly fewer moles than kids 25 years ago, pointing to a major reduction in future melanoma risk.

Published in the British Journal of Dermatology, the study revealed that the average number of moles on people’s bodies has dropped by 47 per cent over the study’s duration.

Between 1992 and 2016, a study of 3,957 participants (158 per year) revealed the average number of moles on the skin of the study participants from SE Queenslanders halved, decreasing by 2 per cent each year [figure].

We see the same trend to lower mole counts in all skin colour types [figure].

Why does this matter? Along with skin colour, mole count is one of the strongest predictors of lifetime melanoma risk, particularly in pale-skinned populations exposed to high levels of ultraviolet (UV) radiation.

With more than half of Australia’s population either born overseas or with a parent born overseas, and a higher proportion of people whose ancestry are generally less susceptible to moles and melanoma, this accounted for about 2 per cent of the overall drop we recorded.

QIMR Berghofer researchers, Dr David Duffy and Dr Gu Zhu believe the most likely reason for the decline is reduced sun exposure before age 12, a critical period for mole development. This behavioural shift reflects decades of sun safety education, including the iconic Slip, Slop, Slap campaigns—much of it informed by QIMR Berghofer research, led by Professor Adele Green AC and supported by the Queensland Cancer Council over four decades.

This trend suggests that public health campaigns and early-life sun protection are working—and could significantly reduce melanoma rates for future generations.