The presence of monoiodinated derivates of daidzein and genistein in human urine and its effect on thyroid gland function

► We try to investigate if daidzein and genistein may enter human thyreocyte. ► Search for daidzein and genistein iodinated derivates in human urine. ► Monoiodinated genistein was found in 60% of probands using phytoestrogens. ► Steroid and thyroid hormone levels were unaffected. ► Use of phytoestrogen dietary supplements is not associated with development of thyroid gland disorders.