Study: Phytoestrogen Content of Foods of Animal Origin

CAMBRIDGE, U.K.—Phytoestrogens are naturally occurring plant-based molecules with weak estrogenic activity that may influence chronic diseases. To assess their effects, researchers accurately must assess dietary exposure; however, most existing analyses have focused on plant-based foods and there is little information on phytoestrogens in animal foods, leading to an underestimation of intake.

Researchers undertook a comprehensive study of phytoestrogen content in animal food and found the phytoestrogen content (isoflavones: biochanin A, daidzein, formononetin, genistein, and glycitein; lignans: secoisolariciresinol and matairesinol; coumestrol; equol; enterolactone; and enterodiol) in 115 animal foods (including milk and milk-products, eggs, meat, fish, and seafood) and vegetarian substitutes. They detected phytoestrogens in all foods analyzed and that most foods (except for fish, seafood, and butter) contained mammalian phytoestrogens (enterolignans and equol).

Source: American Chemical Society: Phytoestrogen Content of Foods of Animal Origin: Dairy Products, Eggs, Meat, Fish, and Seafood