Genistein supplementation has no effects on vitamin D levels in healthy Spanish postmenopausal women.

In vitro studies have shown that genistein inhibits the CYP240 enzyme, which is involved in the degradation of 1,25-dihydroxycholecalciferol and its precursor 25-hydroxycholecalciferol, and increases their plasma levels. However, no clinical studies have primarily assessed the synergistic effect of isoflavones on vitamin D levels. The aim of this study was to evaluate the possible additive effect of genistein supplementation on vitamin D levels, calcium metabolism and bone remodeling markers in healthy postmenopausal women during the spring-summer months.

Estrogen receptor genes polymorphisms determine serum lipid profile in healthy postmenopausal women treated with calcium, vitamin D, and genistein.

Cardiovascular risk increases in women after menopause. Unfavorable lipid-lipoprotein changes due to a lack of estrogens may have an important role in this context. Estrogen actions are mainly mediated by their binding to two estrogen receptors (ERs) whose signaling may be conditioned by different factors.

Association Between Bat Vitamin D Receptor 3' Haplotypes and Vitamin D Levels at Baseline and a Lower Response After Increased Vitamin D Supplementation and Exposure to Sunlight.

The aim of this study was to evaluate the relationship between vitamin D levels at baseline and after 12 weeks of supplementation/exposure to sunlight and VDR genotypes (BsmI, TaqI and ApaI) and haplotypes in a homogeneous population of postmenopausal women. We made a prospective study in which 151 women were randomized to two groups: One with 1000 mg of calcium and 800 IU vitamin D supplementation (102 women) and a placebo group with neither calcium or vitamin D supplementation (49 women). The follow-up was from May to September 2012.

The Effect of Genistein Supplementation on Vitamin D Levels and Bone Turnover Markers during the Summer in Healthy Postmenopausal Women: Role of Genotypes of Isoflavone Metabolism.

Aims: The objective of this study was to determine whether vitamin D and genistein supplementation had an additive beneficial effect on levels of vitamin D and bone markers and whether this effect was mediated by genes regulating isoflavone metabolism.

Materials And Methods: We carried out a prospective study in postmenopausal women randomized to calcium and vitamin D supplementation or calcium, vitamin D, and genistein supplementation. Vitamin D, parathyroid hormone (PTH), cross-linked C-telopeptide (CTX), and procollagen 1 N-terminal (P1NP) were determined by electrochemiluminescence.