FECAL LIGNAN AND ISOFLAVONOID EXCRETION IN PREMENOPAUSAL WOMEN CONSUMING FLAXSEED POWDER

Lignans and isoflavonoids are diphenolic compounds found in plant food s, particularly whole grains and legumes, They have been shown to have anticarcinogenic properties in animal and cell studies, and have been associated with reduced cancer risk in epidemiological studies, In or der to perform further epidemiological and metabolic studies on these compounds, it is necessary to be able to monitor concentrations in bio logical samples, In this study, we examined the effects of consumption of flaxseed, a concentrated source of lignans, on fecal lignan excret ion and evaluated the effect of high lignan consumption on fecal excre tion of isoflavonoids, Thirteen women were studied for two diet period s of three menstrual cycles each in a cross-over design, During the co ntrol period, they consumed their usual diets; during the treatment pe riod they consumed their usual diets supplemented with 10 g/day ground flaxseed, Feces were collected on days 7-11 of the last menstrual cyc le in each diet period, Five-day fecal composites were analyzed for li gnans and isoflavonoids by isotope dilution gas chromatography-mass sp ectrometry. Fecal excretion of the lignans enterodiol, enterolactone, and matairesinol increased significantly with flax consumption, from 8 0.0 +/- 80.0 (SD) to 2560 +/- 3100; 640 +/- 480 to 10,300 +/- 7580; an d 7.33 +/- 10.0 to 11.9 +/- 8.06 nmol/day, respectively, There were no differences in fecal excretion of the isoflavonoids, daidzein, equol, genistein, and O-demethylangolensin.