Lignan Research: Menopause

In a 2002 Canadian study to investigate flaxseed dietary supplement (enterolactone precursors), versus hormone replacement therapy in hypercholesterolemic menopausal women (2002) flaxseed was shown to improve mild menopausal symptoms and to lower glucose and insulin levels1.

In a double-blind, randomized, entry-exit, cross-over study at Monash University (Australia) designed to assess the effects of three dietary manipulations--soy (isoflavone) and linseed diets (enterolactone precursors) and a wheat diet participants consuming linseed had a 41% (p < 0.009) reduction in hot flush rate. The study concluded that that phytoestrogens in soy and linseed (enterolactone precursors) may be of use in ameliorating some of the symptoms of menopause2.

In another Australian study conducted at the Brighton Medical Clinic, Murkies et al investigated the oestrogen-like action of Soy (isoflavones) and wheat flour (enterolactone precursors). The study involved 58 postmenopausal women (age 54, range 30-70 years) with at least 14 hot flushes per week. Hot flushes were significantly decreased in both the soy and wheat flour groups (40% and 25% reduction). Overall menopausal symptom scores also decreased significantly in both groups3.

A new study conducted by researchers at the Julius Center for Health Sciences and Primary Care in Utrecht (Netherlands) links lignans to maintenance of cognitive function in postmenopausal women. The Dutch researchers, whose study is published in the Journal of Nutrition (May, 2005) set out to examine how dietary intake of two phytoestrogens, lignans and isoflavones, in the typical Western diet may affect cognitive function in postmenopausal women. The study involved 394 healthy postmenopausal women who had an intact uterus, at least one intact ovary and had not used hormonal replacement therapy since their last menstrual period. Of these women, 196 experienced a natural menopause between 1969 and 1979 and 207 between 1987 and 1989. Their intake of phytoestrogens during the year prior to enrolment in the study was estimated by a validated food frequency questionnaire. Cognitive function was assessed by a mini-mental state examination (MMSE), which involved questions and tasks associated with orientation, registration, attention, calculation, recall and language. After adjustment for confounders, women who consumed higher levels of lignans performed better in the MMSE, and the results were more pronounced amongst the women who experienced menopause between 1969 and 1979. Isoflavone intake was not related to cognitive function4.