Samira Faraji; Rasoul Zarrin; Asma Zamanian; Reza Hajizadeh; Parvin Ayremlou; Behzad Rahimi
Volume 22, Issue 7 , 2020
Abstract
Background: Hypertension is one of the most serious global concerns since it has affected over 1.2 billion people.
Objectives: The present study aimed to determine the effect of vitamin D supplementation on blood pressure, fasting blood sugar, and lipid profile in hypertensive patients with ...
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Background: Hypertension is one of the most serious global concerns since it has affected over 1.2 billion people.
Objectives: The present study aimed to determine the effect of vitamin D supplementation on blood pressure, fasting blood sugar, and lipid profile in hypertensive patients with vitamin D deficiency.
Methods: In this double-blinded randomized placebo-controlled clinical trial study, 116 hypertensive patients (intervention and placebo groups, 58 each) with vitamin D deficiency (< 30 ng/mL with ECL) for 14 weeks, started from the beginning of autumn 2019 in Seyed-al-Shohada Educational Hospital in Urmia City. Fifty-five patients (49%) were male with the mean vitamin D 15.89 ± 5.09 ng/mL and 57 females with 17.29 ± 6.31 ng/mL. In a stratified blocked randomization scheme, the patients were randomly allocated into similar sized intervention and control groups based on body mass index (BMI), then the randomization with four block size was performed in each of strata by random allocation software. The intervention group received six doses of 50,000 IU vitamin D supplements for 6 weeks, then two supplements for two following months (one capsule per month). Blood pressure (24/h blood pressure measured by an ambulatory blood pressure monitoring device), vitamin D, FBS, and lipid profile (HDL, LDL, CL, and TG) were all measured at baseline and end of the study. Physical activity (measured by short IPAQ questionnaire), sun exposure using a questionnaire, dietary intake of vitamin D using three 24-hour recalls during the intervention, and anthropometric indices were measured at baseline, middle, and end of the study. Fifty-six patients in each group completed the study. The study was approved by the Ethics Committee of the Urmia University of Medical Sciences (ethics code: IR.UMSU.REC.1398.192).
Results: The office blood pressure, 24-h systolic blood pressure (SBP) and diastolic blood pressure (DBP), nighttime SBP and DBP were significantly reduced in the intervention group compared to the control group, whereas the reduction of daytime SBP and DBP was not statistically significant. Vitamin D supplementation significantly decreased serum triglyceride, cholesterol, and LDL levels.
Conclusions: Vitamin D supplementation had positive effects on blood pressure, triglyceride, cholesterol, and LDL levels in patients with low serum vitamin D.
Rasoul Zarrin; Parvin Ayremlou; Farzaneh Ghassemi
Volume 19, Issue 3 , March 2017, , Pages 1-8
Abstract
Background: Low serum levels of vitamin D are supposed to contribute to the incidence of diabetes; therefore, vitamin D supplementation may reduce the incidence of diabetes in individuals with prediabetes.Objectives: The aim of this current study was to examine the effect of vitamin D supplementation ...
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Background: Low serum levels of vitamin D are supposed to contribute to the incidence of diabetes; therefore, vitamin D supplementation may reduce the incidence of diabetes in individuals with prediabetes.Objectives: The aim of this current study was to examine the effect of vitamin D supplementation on the glycemic status and percentage of body fat mass in adults with prediabetes.Methods: In a 3-month randomized placebo-controlled supplementation trial, 120 eligible subjects were randomly assigned in a vitamin D or placebo group. They were stratified according to the percentage of body fat mass into four blocks to receive 1000 IU/daily vitamin D or an identical placebo tablet respectively, for 3 months. The study was conducted from January to March of 2016 in Urmia in the North West of Iran. Participants were adults aged 18 to 70 with prediabetes. The fasting blood sugar (FBS), glycated hemoglobin (HbA1c), homeostasis model assessment of insulin resistance (HOMA-IR), serum 25(OH)D levels, and percentage of body fat mass were assessed before and after the intervention.Results: The comparison of changes from baseline between two groups showed a significant inverse association between the changes in serum 25(OH)D and changes in FBS (-4.64 ± 11.38 compared with -2.11 ± 9.15 for placebo; P = 0.03), HOMA-IR (-0.73 ± 4.2 compared with 0.44 ± 4.4 for placebo, P = 0.01) and serum insulin (-1.98 ± 15.25 compared with 2.47 ± 15.85 for placebo; P = 0.007) but not in the percentage of body fat mass (-0.28 ± 0.77 compared with -0.39 ± 2.82 for placebo; P = 0.39).Conclusions: The study demonstrated that 1000 IU vitamin D supplementation for 3 months can decrease the insulin resistance in individuals with prediabetes; however, it has no significant effect on body fat mass percentage.