Phytoestrogen Content of Cereals and Cereal-Based Foods Consumed in the UK

Abstract

Dietary phytoestrogens may be involved in the occurrence of chronic diseases. Reliable information on the phytoestrogen content in foods is required to assess dietary exposure and disease risk in epidemiological studies. However, there is little information on isoflavone, lignan, and coumestrol content of cereals and cereal-based foods, leading to an underestimation of intake. This is the first study of phytoestrogens (isoflavones: biochanin A, daidzein, formononetin, genistein, glycitein; lignans: matairesinol, secoisplariciresinol; coumestrol) in a comprehensive selection of 101 cereals and cereal-based foods—including breads, breakfast cereals, biscuits, pasta and rice—consumed in the UK using a sensitive LCMS technique with ¹³ C-labelled internal standards. Phytoestrogens were detected in all foods analyzed; bread contained the highest amount of phytoestrogens—many as isoflavones—with an average content of 375 ± 67 μ g/100 g wet weight (excluding soya-linseed bread with 12,000 μ g/100 g). Most other foods contained less than 100 μ g/100 g, many as lignans. Our study shows that all foods analyzed contained phytoestrogens, with the highest amount found in breads, making them one of the main sources of dietary phytoestrogens in the UK. These results will allow a more accurate estimation of exposure to dietary phytoestrogens.

ACKNOWLEDGMENTS

This work was funded by the United Kingdom Food Standards Agency (FSA), contract number T05028, and the Medical Research Council (MRC).

Notes

^a Data are given as μg per 100 g wet weight; the data are the average of 3 different samples analyzed in duplicate.—indicates content was below the limit of detection.