title: Soy Reduces Bone Turnover Markers in Women During Early Menopause: A Randomized Controlled Trial.
abstract: Menopausal estrogen loss leads to an increased bone loss. Soy isoflavones can act as selective estrogen receptor modulators, their role in bone turnover is unclear. The primary outcome was assessing changes in plasma bone turnover markers. The secondary outcomes were assessing changes in cardiovascular risk markers including insulin resistance, blood pressure, and lipid profile. We performed a double-blind randomized parallel study in which 200 women within 2 years after the onset of their menopause were randomized to 15 g soy protein with 66 mg isoflavone (SPI) or 15 g soy protein alone (SP), daily for 6 months. There was a significant reduction in type I collagen crosslinked beta C-telopeptide (βCTX) (bone-resorption marker) with SPI supplementation (0.40 ± 0.17 versus 0.15 ± 0.09 μg/L; p < 0.01) compared to SP supplementation (0.35 ± 0.12 versus 0.35 ± 0.13 μg/L; p = 0.92) after 6 months. There was also a significant reduction in type I procollagen-N-propeptide (P1NP) (bone formation marker) with SPI supplementation (50.5 ± 25.0 versus 34.3 ± 17.6 μg/L; p < 0.01), more marked between 3 and 6 months. Following SPI there was a significant reduction in fasting glucose, fasting insulin, insulin resistance, and systolic blood pressure whereas no significant changes in these parameters was observed with SP. There were no significant changes in fasting lipid profile and diastolic blood pressure with either preparation. There was a significant increase in TSH and reduction in free thyroxine (p < 0.01) with SPI supplementation though free tri-iodothyronine was unchanged. In conclusion, soy protein with isoflavones may confer a beneficial effect on bone health, analogous to the mode of action of antiresorptive agents, albeit to a less magnitude. There was a significant improvement of cardiovascular risk markers, but a significant increase in TSH and reduction in free thyroxine after SPI supplementation indicating a detrimental effect on thyroid function. © 2016 American Society for Bone and Mineral Research.
authors.affiliation: Academic Diabetes, Endocrinology and Metabolism, Hull York Medical School, University of Hull, Hull, UK.
authors.forename: Thozhukat
authors.initials: T
authors.lastname: Sathyapalan
authors.affiliation: Academic Diabetes, Endocrinology and Metabolism, Hull York Medical School, University of Hull, Hull, UK.
authors.forename: Mo
authors.initials: M
authors.lastname: Aye
authors.affiliation: Department of Academic Cardiology, University of Hull, Hull, UK.
authors.forename: Alan S
authors.initials: AS
authors.lastname: Rigby
authors.affiliation: Norwich Medical School, Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK.
authors.forename: William D
authors.initials: WD
authors.lastname: Fraser
authors.affiliation: European Food Safety Authority, Parma, Italy.
authors.forename: Natalie J
authors.initials: NJ
authors.lastname: Thatcher
authors.affiliation: Department of Clinical Chemistry, Sidra Medical and Research Center, Doha, Qatar.
authors.forename: Eric S
authors.initials: ES
authors.lastname: Kilpatrick
authors.affiliation: Weill Cornell Medical College Qatar, Doha, Qatar.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Atkin
mesh_terms: D000886:Anthropometry; D015415:Biomarkers / Q000032:analysis* / Q000097:blood; D016723:Bone Remodeling / Q000187:drug effects*; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D008593:Menopause / Q000097:blood* / Q000502:physiology*; D008875:Middle Aged; D010455:Peptides / Q000097:blood; D030262:Soybean Proteins / Q000494:pharmacology*
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D007529:Isoflavones; D010455:Peptides; D030262:Soybean Proteins; C052929:collagen type I trimeric cross-linked peptide
keywords: BONE TURNOVER MARKERS; CADIOVASCULAR RISK MARKERS; P1NP; PHYTOESTROGENS; SOY ISOFLAVONES; THYROID FUNCTION; βCTX