Effects of vitamin D supplementation on insulin resistance and dyslipidemia in overweight and obese premenopausal women

Abstract

Introduction Vitamin D deficiency is a common problem, and it is related to increased risk of obesity, metabolic syndrome, atherosclerosis, and cardiovascular disease. Vitamin D has a beneficial effect on dyslipidemia and insulin secretion. We aimed to investigate the impact of vitamin D 3 supplementation on anthropometric and laboratory parameters in overweight and obese premenopausal women. Material and methods Seventy-two overweight and 50 obese vitamin-D-deficient premenopausal women (mean age: 43.1 ±10.4 years) were included in the study. Baseline mean 25-hydroxyvitamin D [25(OH)D] level was 6.1 (min.–max. = 2.9–15.8) ng/ml in overweight and was 5.6 (min.–max. = 3.0–22.0) ng/ml in obese subjects. At baseline and at the sixth month of supplementation, serum 25(OH)D, intact parathormone (iPTH), calcium, phosphorus, homeostasis model assessment of insulin resistance (HOMA-IR), and lipid profiles were assessed. Results Following vitamin D 3 supplementation in overweight and obese subjects, serum 25(OH)D increased from 6.1 to 34.7 ng/ml and 5.6 to 34.7 ng/ml, respectively ( p < 0.001). At the sixth month of supplementation in both overweight and obese subjects, a significant reduction was detected in HOMA-IR ( p < 0.001), low-density lipoprotein cholesterol (LDL-C) ( p = 0.046, p = 0.044; respectively) and iPTH levels ( p ≤ 0.001, p < 0.001; respectively). A negative adjusted correlation was found between changes in 25(OH)D and HOMA-IR ( r = –0.581, p < 0.001; r = –0.389, p = 0.005; respectively). A 1 ng/ml increase in serum 25(OH)D level led to a 0.30-fold reduction in HOMA-IR level ( p = 0.002). Conclusions Our results support the effect of vitamin D 3 supplementation in HOMA-IR and LDL-C improvement in both obese and overweight subjects. Further studies focused on low serum 25(OH)D levels with insulin resistance and dyslipidemia are needed.

The effect of clomiphene citrate, herbal mixture, and herbal mixture along with clomiphene citrate on clinical and para-clinical parameters in infertile women with polycystic ovary syndrome: a randomized controlled clinical trial

“…Recent research has confirmed that vitamin D 3 supplementation has a beneficial effect on HOMA-IR and dyslipidemia [59]. Furthermore, in one of the latest studies comparing the HOMA-IR method and insulin resistance (Belfiore) index, it was concluded that insulin resistance (Belfiore) index diagnosed more cases of insulin resistance in women with PCOS compared to HOMA-IR [60]).…”

<p>Linking the metabolic syndrome and obesity with vitamin D status: risks and opportunities for improving cardiometabolic health and well-being</p>

“…In a mouse model of T2DM, 8-week supplementation of type 2 diabetes db/db mice with 1,25(OH) 2 D 3 ameliorates hepatic triglyceride accumulation and glucose production via the activation of Ca2+ mediated CaMKKβ/AMPK signaling pathway 68. Imga et al have shown that vitamin D administration in overweight or obese vitamin D-deficient premenopausal women, can result in a significant reduction in LDL-C levels and improvement of IR 69. Effects on vitamin D on postprandial lipid profiles in obese women may be dose-dependent and favors a reduction in LDL and vLDL at lower vitamin D levels, and an elevation of lipids at higher vitamin D doses 70.…”

<p>Low Vitamin D Serum Level Is Associated with HDL-C Dyslipidemia and Increased Serum Thrombomodulin Levels of Insulin-Resistant Individuals</p>

“…7 Vitamin D is believed to impact CVD through various mechanisms including impaired glucose and lipid metabolism pathways. 8 Many of these pathways are relevant to insulin resistance as well, given that insulin resistance is a risk factor for dyslipidemia and low levels of serum 25 (OH)D. 9 Although the association between 25(OH)D and serum lipid profile has been reported in numerous studies, 10,11 this association may vary by insulin resistance status. Epidemiological studies suggest an inverse association between 25(OH)D and serum lipid profile 12 although it is highly controversial which lipid may be affected by increased serum 25(OH)D levels.…”