Development of a food compositional database for the estimation of dietary intake of phyto-oestrogens in a group of postmenopausal women previously treated for breast cancer and validation with urinary excretion

Abstract

The scientific literature contains evidence suggesting that women who have been treated for breast cancer may, as a result of their diagnosis, increase their phyto-oestrogen (PE) intake. In the present paper, we describe the creation of a dietary analysis database (based on Dietplan6) for the determination of dietary intakes of specific PE (daidzein, genistein, glycitein, formononetin, biochanin A, coumestrol, matairesinol and secoisolariciresinol), in a group of women previously diagnosed and treated for postmenopausal breast cancer. The design of the database, data evaluation criteria, literature data entry for 551 foods and primary analysis by LC-MS/MS of an additional thirty-four foods for which there were no published data are described. The dietary intake of 316 women previously treated for postmenopausal breast cancer informed the identification of potential food and beverage sources of PE and the bespoke dietary analysis database was created to, ultimately, quantify their PE intake. In order that PE exposure could be comprehensively described, fifty-four of the 316 subjects completed a 24 h urine collection, and their urinary excretion results allowed for the description of exposure to include those identified as 'equol producers'.

Phytoestrogens in foods on the Nordic market

“…Other foodstuffs in this category were black bean sauce (53-152 mg/kg fw), soy paste (57-147 mg/kg dw) and defatted soy meal (1,369 mg/kg dw), the latter being used as animal feed Thompson et al, 2006;Clarke et al, 2013a). The high level of isoflavones in miso and tofu was confirmed in studies giving the content in mg/kg dw Song et al, 1998;Wu et al, 2012).…”

“…No data have been found on other mushrooms. No isoflavones were found in a protein preparation called quorn and obtained from microfungi Clarke et al, 2013a).…”

“…Canned tuna contained low levels of most of these isoflavone aglycones on a fw basis: 0.007 mg/kg daidzein, 0.016 mg/kg genistein, 0.001 mg/kg glycitein, and 0.022 mg/kg formononetin , as did the brine from those cans . Clarke et al (2013a) analysed an unspecified sushi dish for isoflavones but could only identify very low levels of genistein and formononetin.…”

“…Not unexpectedly, soy-based hamburger bread (259 mg/kg fw), mince (286 mg/kg fw), miso paste (111 mg/kg fw), soft tofu (225-280 mg/kg fw), tempeh (182 mg/kg fw), ice cream (135 mg/kg fw), and yogurt (102 mg/kg fw) were among the foodstuffs with more than 100 mg total isoflavones/kg fw Horn-Ross et al, 2000;Liggins et al, 2000b;Thompson et al, 2006;Kuhnle et al, 2008a;Clarke et al, 2013a). Other foodstuffs in this category were black bean sauce (53-152 mg/kg fw), soy paste (57-147 mg/kg dw) and defatted soy meal (1,369 mg/kg dw), the latter being used as animal feed Thompson et al, 2006;Clarke et al, 2013a).…”

“…Kuhnle et al (2008a) investigated the levels of lignans in the brine of canned tuna, but only nonquantifiable levels of secoisolariciresinol were found. Clarke et al (2013a) reported 1 mg secoisolariciresinol/kg fw of sushi but did not state which fish was used. In short, seafood represents a negligible contribution to the total lignin intake in consumers.…”