On the potential beneficial effects of indoor tanning: reply from the authors

DEAR EDITOR, We read with great interest the article by Eden et al. entitled ‘Cost-effectiveness of a policy-based intervention to reduce melanoma and other skin cancers associated with indoor tanning’, concluding that banning of indoor tanning would save lives. We agree with the Eden et al. that a cost-effectiveness analysis of indoor tanning is needed. A key limitation of their paper is that they included only the hazardous events and not the beneficial effects of indoor tanning. In our large prospective cohort, indoor tanning was associated with a 20% increased risk of malignant melanoma mortality (hazard ratio 1 2, 95% confidence interval 1 0–1 6), but at the same time a 23% lower all-cause mortality risk (hazard ratio 0 77, 95% confidence interval 0 7–0 8) during the study interval. Thus, indoor tanning seems to give a survival advantage, at least in a low ultraviolet radiation (UV) region. We are well aware that the findings of a prospective observational study do not give causal results. However, the dosedependent relationship, plausible mechanisms, and supporting findings in experimental studies increase the likelihood of a causal relationship between active sun exposure habits and a decreased rate of all-cause mortality. We agree that the greater the UV exposure, the higher the rate of keratinocytic skin cancer. However, as the UV risk factor for malignant melanoma is mainly overexposure, proper targeted guidelines should keep the risk low and optimize health. Furthermore, as indoor tanning is a source of sunlight for underprivileged groups, a ban on indoor tanning might increase health inequalities. We agree with Eden et al. that policymakers need robust economic knowledge when making decisions. Unfortunately, the paper by Eden et al. only gives information on one side of the coin. In addition, there is no proof that banning indoor tanning would save lives in Northern Europe; it is only hypothetical. On the contrary, there is evidence that banning indoor tanning would instead increase the mortality rate due other causes, such as hypertension, thromboembolism and type 2 diabetes mellitus. Thus, a quick fix of a complex problem like banning indoor tanning is unlikely to save lives in the UK or Sweden. Data available in prior papers. A multidisciplinary approach to optimize sun exposure for maximal health benefit, and minimize the risk of malignant melanoma will supposedly be a winning concept. It should be possible to target guidelines against (episodic) overexposure of UV and indoor tanning abuse, and to question the reliance on sun blockers, and still get UV exposure for optimal health.