Abstract
Total plasma iron, copper, zinc and selenium and the dietary intake of these elements were determined in pre-menopausal (pre-m) and post-menopausal (post-m) women mainly with stage I breast cancer (BCA), and in omnivorous (OMN) and vegetarian (VEG) controls. The OMN groups comprised 14 pre-m women (33 ± 6 (SD) years) and II post-m women (57 ± 5 years), and the VEG groups comprised 12 pre-m women (34 ± 7 years) and 11 post-m women (59 ± 5 years). There were 13 pre-m BCA patients (39 ± 7 years) and 10 post-m BCA patients (66 ± 6 years). Fasting plasma samples were obtained on 3 consecutive days, typically four times a year. Dietary assessment was over 5 days by weighing dietary components on a letter balance and analyzing for nutrient components using a computer program. Overall geometric means (1 SD range) for plasma (μmol 1 -1)/dietary (mg/day) elements were: Fe 15-5 (10-3-19-4)/'12-4 (9-4-14-8), Cu 17-5 (14-3-20-7)/1-46 (1-04-1-78), Zn 13-9 (11-2-16-2)/10 0 (7-6-1 l-9), Se 1-41 (1-20-1-59)/31-0 μg/day (8 1-44-2). Except for P-Cu pre-m (16-4 μmoll-1 in controls vs 18-2 μmoll1 in BCA group, p < 0-03) plasma elemental levels themselves did not distinguish BCA from controls. Neither did elemental ratios separate BCA from controls. Only for Se did plasma levels depend directly on intake (correlation coefficient 0-24, p < 0-02). The P-Cu/diet-copper ratio (μmol-1 per mg/day) distinguished pre-m BCA (12-9) from pre-m controls (9-8-OMN, 10-4-VEG; p<0001) and post-m BCA (14-3) from post-m VEG (11-3; p<0-01); this was also true for a parameter of the plasma non-caeruloplasmin copper/diet-copper ratio, perhaps pointing to differences in copper absorption.