Dietary intake of selected micronutrients and breast-cancer risk

The relation between 17 micronutrients and breast-cancer risk was analyzed in a case-control study conducted between 1993 and 1999 in the Swiss Canton of Vaud. Cases were 289 women with incident, histologically confirmed brea st cancer, and controls were 442 women admitted to the same hospital for a wide spectrum of acute non-neoplastic conditions unrelated to long-term mod ifications of diet. Dietary habits were investigated using a validated food -frequency questionnaire. Odds ratios (ORs) were obtained after allowance f or age, education, parity, menopausal status, body mass index, total energy intake and alcohol drinking. For several micronutrients, the ORs tended to decline with increasing tertile of intake, with significant inverse trends in risk for potassium (OR for the highest tertile = 0.21), total carotenoi ds (OR 0.42), lycopene (OR = 0.43), folic acid (OR = 0.45), vitamin C (OR = 0.19), vitamin E (OR = 0.37) and vitamin B-6 (OR 0.54). In a model includi ng a continuous term for the 7 micronutrients significantly related to brea st cancer, the only persisting significant inverse relations were for vitam in C (OR = 0.23) and lycopene (OR = 0.64). (C) 2001 Wiley-Liss, Inc.