The effects of vitamin D supplementation on muscle strength and mobility in postmenopausal women: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: The results obtained from previous trials regarding the effects of vitamin D supplementation on muscle strength and mobility in postmenopausal women have been inconsistent. This systematic review and meta-analysis of randomised controlled trials (RCTs) aimed to investigate the effect of vitamin D supplementation on muscle strength and mobility in postmenopausal women. METHODS: A comprehensive search on EMBASE, PubMed, MEDLINE and SCOPUS was performed to identify relevant articles published up to 28 March 2019. RCTs published in English measuring the effect of all forms and doses of vitamin D supplementation with or without calcium on muscle strength and mobility outcomes in postmenopausal women were included. RESULTS: In total, 29 eligible studies were included in the systematic review. The pooled findings using a random effects model showed that vitamin D supplementation insignificantly increased hand grip strength (HGS) as the measurement of muscle strength (MD = 0.656; 95% confidence interval = -0.037 to 1.350, P = 0.06). However, it did not affect timed-up-and-go (TUG) as the measurement of mobility (MD = 0.118; 95% confidence interval = -0.655 to 0.892, P = 0.76). The subgroup analyses showed that vitamin D supplementation improved HGS with respect to dosages >1000 IU day-1 (P = 0.016), a treatment duration of 3 months (P Ë‚ 0.001) and subjects with baseline vitamin D <30 ng mL-1 (P = 0.033). CONCLUSIONS: The present review demonstrates that vitamin D supplementation resulted in small but nonsignificant improvements in muscle strength compared to control in postmenopausal women. No significant effect was observed in mobility after vitamin D administration.

Unhealthy dietary patterns are related to low ceruloplasmin in female nurses.

BACKGROUND AND OBJECTIVE: Few studies have examined the relationship between dietary patterns and antioxidant status. We aimed to explore the association between major dietary patterns and oxidative stress biomarkers including serum protein carbonyl (PC), ceruloplasmin and total antioxidant capacity (TAC). METHOD: In this cross-sectional study, we randomly selected 320 female nurses aged 20-45 years. General information of participants was collected by trained interviewers. Their weight and height were measured and dietary intakes were determined by the 147-food-item semiquantitative food frequency questionnaire. Dietary patterns were derived by principal component analysis of yielding 25 food groups. In this study, 90 subjects were randomly selected from all participants with serum levels of PC, ceruloplasmin and TAC measured further. To determine the association between dietary patterns' score and oxidative stress biomarkers, multiple linear regression analysis was conducted. RESULTS: Three dietary patterns were derived: healthy, unhealthy and traditional. After adjusting for several confounding factors, the unhealthy dietary pattern was inversely related to the serum concentration of ceruloplasmin and PC (p<0.05). The relationship between other dietary patterns and antioxidant biomarkers was not significant. CONCLUSIONS: According to the results of this study, unhealthy dietary patterns may have an adverse effect on serum ceruloplasmin.

Higher intake of dietary n-3 PUFA and lower MUFA are associated with fewer menopausal symptoms.

OBJECTIVE: This study aimed to investigate the association between dietary fat quality and menopausal symptoms. METHODS: We carried out a cross-sectional study with 393 Iranian postmenopausal women. Dietary intakes and menopausal symptoms were assessed, using a validated food frequency questionnaire and a menopausal rating scale (MRS) questionnaire, respectively. Participants were divided into low and high total MRS and its domain scores. RESULTS: Women in the highest quartiles of monounsaturated fatty acids (MUFA) had higher somatic symptoms compared with women in the lowest quartile (odds ratio [OR] 3.41; 95% confidence interval [CI] 1.17-9.95). Women in the highest quartiles of n-3 polyunsaturated fatty acids (PUFA) (OR 0.58; 95% CI 0.32-1.05), eicosapentaenoic acid (EPA) (OR 0.66; 95% CI 0.37-1.20), and n-3:n-6 PUFA ratio (OR 0.49; 95% CI 0.25-0.97) had lower somatic symptoms compared to the lowest quartiles. The OR for psychological symptoms decreased from the lowest to the highest quartiles of n-3 PUFA (OR 0.47; 95% CI 0.20-1.11) and n-3:n-6 PUFA ratio (OR 0.46; 95% CI 0.24-0.86). Higher intakes of EPA (OR 0.53; 95% CI 0.29-0.99) and docosahexaenoic acid (OR 0.51; 95% CI 0.27-0.95) were found to be related with fewer urogenital symptoms. CONCLUSION: Consuming diets low in MUFA intake, but high in n-3 PUFA, and with a more favorable ratio of n-3:n-6 PUFA may be helpful for improving menopausal symptoms.