Controversies concerning the use of phytoestrogens in menopause management: Bioavailability and metabolism

It has been proposed that the use of phytoestrogens (PE) in menopausal therapy could be beneficial to woman health, particularly with respect to hot flushes. Indeed, PE may compensate the lack of endogenous 17β-estradiol occurring during menopause. However, therapeutic benefits remain questionable, as highlighted by recent publications. Indeed, data are often subjected to controversy since a number of exogenous and endogenous factors influencing the responsiveness of patients are not sufficiently taken into account. In the present paper, we will discuss the role of bioavailability and metabolism in the instability of individual response to PE.