Sturgeon SR, Heersink JL, Volpe SL, Bertone-Johnson ER, Puleo E, Stanczyk FZ, Sabelawski S, Wahala K, Kurzer MS, Bigelow C. Effect of dietary flaxseed on serum levels of estrogens and androgens in postmenopausal women. Nutr Cancer. 2008; 60(5):612-8.