Breast cancer and alcohol intake

Breast cancer and alcohol intake

854 Information Section benefits of supplementation in those known to have the disease are as yet unclear. In a recent study in Finland, 1862 male s...

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854

Information Section

benefits of supplementation in those known to have the disease are as yet unclear. In a recent study in Finland, 1862 male smokers with a history of heart disease were randomly assigned to receive daily supplements of ct-tocopherol (50 mg), ~-carotene (20 mg), both vitamins, or a placebo, for over 5 years. The cohort was identified from over 29,000 participants (aged 50-69 years) in a study designed to assess the effect of the vitamins on development of lung cancer in male smokers--the Alpha-Tocopherol, BetaCarotene (ATBC) Cancer Prevention Study. There was no convincing evidence of a reduction in the number of major coronary events (non-fatal myocardial infarction or fatal heart attack) in any supplementation group. Indeed, there was an elevated risk of fatal heart disease in those taking the I~-carotene supplement [relative risk (R.R) 1.75, 95% confidence interval (CI) 1.16-2.64] or the combined a-tocopherol/~carotene (ILK 1.58, 95% CI 1.05-2.40) (Rapola J.M. et al., Lancet 1997, 349, 1715).

Trans- and fishy fatty acids and heart disease Further interesting data relating to heart disease to emerge from the ATBC study follows the analysis of fatty acid intake among about 22,000 participants who completed a detailed dietary questionnaire. In over 6 years of foUow-up, there were almost 1400 major coronary events, including 635 deaths. An increased risk was linked to the intake of strans-fatty acids 0LR 1.39, 95% CI 1.09-1.78, comparing an intake of 6.2 g/day with 1.3 g/day) and in those with a higher intake of omega-3 fatty acids from fish (RR 1.30, 95% CI 1.01-1.67) (Pientinen P. et al., American Journal of Epidemiology 1997, 145, 876).

Plasma homocysteine and heart disease The widely held belief that a high plasma level of the amino acid homocysteine is a risk factor for heart disease receives further support from a Europe-wide study. In a comparison of 750 individuals with coronary heart disease or vascular disease and 800 controls, all aged under 60 years, those with the highest plasma homocysteine levels (in the top fifth of the control distribution) showed a doubling in risk of vascular disease compared with the remainder (RR 2.2, 95% CI 1.6-2.9). This level of risk was equivalent to that of a high serum cholesterol level or smoking, and the effect was exacerbated by smoking and high blood pressure. There was some suggestion of a reduced risk in

vitamin users. The investigators, drawn from a wide range of European Institutes, argue that "it is time to consider whether existing recommended daily allowances of the vitamins that modulate homocysteine metabolism are adequate, and to undertake randomized controlled trials of the effects of relic acid and perhaps pyridoxine in the secondary prevention of cardiovascular disease" (Graham I.M. et al., Journal of the American Medical Association 1997, 277, 1775).

Breast cancer and alcohol intake A US study of 1645 young (aged 20-44 years) breast cancer patients and about 1500 healthy controls from the local general population has found an association between recent drinking habits and risk of breast cancer. A RR of 1.7 (95% CI 1.23-2.5) was linked to the intake of at least 14 alcoholic drinks/ week over the previous 5 years. The investigators felt that the data "add support to the accumulating evidence that alcohol consumption is associated with increased risk of breast cancer" and that it "acts at a late stage in breast carcinogenesis" (Swanson C.A. et al., Epidemiology 1997, 8,231).

Hormones and breast cancer A supplement to the journal Environmental Health Perspectives reviews hormonal metabolism and the effects of environmental exposures on oestrogenic activity in relation to breast cancer. The papers were presented at a workshop held in September 1995 in New Orleans, Louisianna (Environmental Health Perspectives 1997, 105 (Suppl. 3), 557).

Indole-3-corbinol and urinary hormone levels Indole-3-carbinol (found in the cabbage,cauliflower family of vegetables) has been shown to change the urinary profile of a range of oestrogens and their metabolites in volunteers given oral doses of 6-7 mg/kg body weight/day for 1 week (males) or 2 months (females). The investigators believed that the findings may indicate a chemopreventive activity of indole-3-carbinol against breast cancer in humans (Michnovicz J.J. et al., Journal of the National Cancer Institute 1997, 89, 718).

Blsphenol A exhlblts a hormonal action in rats Bisphenol A has been shown to mimic the hormone oestradiol by stimulating the secretion of prolactin from the pituitary cells in one of two tested strains of laboratory rat. Exposure was estimated to be 40-45 ~g/day. The mode of