First-morning urinary melatonin and breast cancer risk in the Guernsey Study.

It has been hypothesized that suppressed nocturnal melatonin production is associated with an increased risk of breast cancer, but results from several small prospective studies of the association have been inconclusive. We examined the association between nocturnal melatonin and breast cancer risk in a case-control study nested within the Guernsey III Study, a British prospective cohort study (1977-2009). Concentrations of 6-sulfatoxymelatonin were measured in prediagnostic first-morning urine samples from 251 breast cancer cases and 727 matched controls. Conditional logistic regression models were used to calculate odds ratios for breast cancer in relation to 6-sulfatoxymelatonin level. No significant association was found between 6-sulfatoxymelatonin level and breast cancer risk, either overall (for highest third vs. lowest, multivariable-adjusted odds ratio = 0.90, 95% confidence interval: 0.61, 1.33) or by menopausal status. However, in a meta-analysis of all published prospective data, including 1,113 cases from 5 studies, higher 6-sulfatoxymelatonin levels were associated with lower breast cancer risk (for highest fourth vs. lowest, odds ratio = 0.81, 95% confidence interval: 0.66, 0.99). In summary, we found no evidence that 6-sulfatoxymelatonin level in a first-morning urine sample was associated with breast cancer risk among British women. However, overall the published data suggest a modest inverse association between melatonin levels and breast cancer risk. Further data are needed to confirm this association.

Tackling the tobacco challenge: achieving 'healthy public policy' in tobacco control in Guernsey.

Scientific evidence identifying smoking as the major cause of poor health and premature death in both industrialised and increasingly in developing countries is now overwhelming. Despite this, for a variety of reasons, there has been reluctance amongst many Governments including that of Britain, to take all logical action necessary to restrict and reduce smoking, especially amongst the young. The States of Guernsey in the Channel Islands has recently agreed to introduce an integrated package of measures designed specifically to make smoking less attractive and less accessible and less affordable to young people in an attempt to reduce the number of addicted adult smokers. These measures include a total ban of all public advertising of tobacco, apart from at point of sale, a substantial price rise followed by further price rises for a minimum period of five years, a raising of the minimum age for the purchase of tobacco from 16 to 18 years, an increase in the size and content of pack health warnings, and increased funding for specific nonsmoking health promotion activities. The various barriers to achieving these reforms are described.