The relationship between vitamin D and obesity

Nutritional Status and Serum Levels of Micronutrients in an Elderly Group Who Participate in the Program for Complementary Food in Older People (PACAM) from the Metropolitan Region, Santiago de Chile

The increase in the Chilean elderly population has promoted public policies to favor an adequate nutrition in later life. This study evaluated the nutritional status, micronutrients intake and serum micronutrients levels of an elderly group beneficiary of the PACAM from the Metropolitan Region, Santiago de Chile. Anthropometric and dietary survey (24 h food recalls) were assessed in 182 elderly individuals (60 and 80 years old). Blood serum collection was used to measure the micronutrient status. The sample was comprised by 12.6%, 46.1%, 28.0% and 13.2% of underweight, normal weight, overweight and obese subjects, respectively. Women presented 11% of underweight, 45% of normal weight and 44% of overweight and obese, while men—18%, 50% and 32%, respectively. Only the 63% of the elderlies consumed PACAM foods, reaching average daily intakes below (50%) the recommended daily serving. Serum deficiencies of 25-hydroxyvitamin D (88%), vitamin B₁₂ (33%) and calcium (36%) were observed, being the highest ones in the PACAM foods women (60–75 years old). Chilean elderlies presented mainly a normal weight; however, an important proportion of overweight/obese subjects was observed. Although PACAM foods consumption significantly increased the micronutrient intake, it was not enough to ensure an adequate serum micronutrient levels in the elderly.

Vitamin D status of overweight and obese Bangladeshi adults

BACKGROUND

Both obesity and vitamin D deficiency are pandemics and both have influences on cardiovascular parameters. The reported prevalence of vitamin D deficiency in obesity is high. Data relating to vitamin D status in obese is currently lacking in Bangladesh.

OBJECTIVE

To discover the vitamin D status in Bangladeshi overweight and obese adults.

SUBJECTS AND METHODS

This cross-sectional study, conducted in a specialized endocrine center of Bangladesh, evaluated 500 consecutive overweight or obese subjects, diagnosed according to body mass index (BMI) categories applicable to the south Asian population. Serum 25(OH)D was measured by using the enzyme-linked fluorescent assay (ELFA) method, and the cutoffs described by the Endocrine Society were used to define vitamin D status.

RESULTS

The mean age of the study subjects was 45.85 (±11.41) years; most (59.6%) of them were in the age group 40-59 years; almost three-fourth (72.4%) were females; an almost equal number of them came from urban (33.8%), semi-urban (29.6%), and rural (36.6%) areas; three-fourth (74.2%) were homemaker. Their mean BMI was 29.54 (±3.11) kg/m2; the frequencies of overweight, class I obesity, class II obesity, and class III obesity were 27.6%, 57.4%, 12.2%, and 2.8%, respectively. The mean serum 25(OH)D level was 25.25 (±11.97) ng/mL. 27.4% were sufficient, and 33.4% were insufficient for vitamin D, whereas 39.2% had vitamin D deficiency. The 25(OH)D level did not differ across different age groups, gender, residence, education status, occupation, and income status. The 25(OH)D levels were also indifferent in overweight, obese class I, obese class II, and obese class III subjects. None of the demographic, anthropometric, and biochemical variables (except low-density lipoprotein cholesterol) correlated with 25(OH)D levels.

CONCLUSIONS

The prevalence of vitamin D deficiency in overweight and obese Bangladeshi adults is very high.

Logistic LASSO and Elastic Net to Characterize Vitamin D Deficiency in a Hypertensive Obese Population

Aim: The primary objective of our research was to compare the performance of data analysis to predict vitamin D deficiency using three different regression approaches and to evaluate the usefulness of incorporating machine learning algorithms into the data analysis in a clinical setting. Methods: We included 221 patients from our hypertension unit, whose data were collected from electronic records dated between 2006 and 2017. We used classical stepwise logistic regression, and two machine learning methods [least absolute shrinkage and selection operator (LASSO) and elastic net]. We assessed the performance of these three algorithms in terms of sensitivity, specificity, misclassification error, and area under the curve (AUC). Results: LASSO and elastic net regression performed better than logistic regression in terms of AUC, which was significantly better in both penalized methods, with AUC = 0.76 and AUC = 0.74 for elastic net and LASSO, respectively, than in logistic regression, with AUC = 0.64. In terms of misclassification rate, elastic net (18%) outperformed LASSO (22%) and logistic regression (25%). Conclusion: Compared with a classical logistic regression approach, penalized methods were found to have better performance in predicting vitamin D deficiency. The use of machine learning algorithms such as LASSO and elastic net may significantly improve the prediction of vitamin D deficiency in a hypertensive obese population.

Does Hashimoto's Thyroiditis Increase the Risk of Cardiovascular Disease in Young Type 1 Diabetic Patients?

Background: Immunological and hormonal disorders have undoubted influence on the development of atherosclerotic process. Autoimmune diseases accompanying type 1 diabetes (T1D) may additionally accelerate atherosclerosis progression and increase the risk of cardiovascular events in the future. The influence of subclinical hypothyroidism on the cardiovascular system, in particular, has recently aroused great interest. The aim of our study was to assess intima-media thickness (cIMT) of common carotid arteries and the occurrence of classical atherosclerosis risk factors together with selected new biomarkers of cardiovascular diseases in young patients with type 1 diabetes mellitus coexisting with Hashimoto's disease (HD). Patients and Methods: The study included 50 adolescents and young adults with T1D with mean age 17.1 ± 3 years, with mean diabetes duration of 10.5 ± 3.3 years, including 20 patients with diagnosed HD: T1D and HD(+), and 30 patients with no additional diseases: T1D and HD(-). Twenty-two healthy, age-matched volunteers formed control group (C). We analyzed mean HbA₁c value from all years of disease, BMI, blood pressure, lipids, new biomarkers of atherosclerosis (hsCRP, adiponectin, myeloperoxidase, NT-proBNP peptide, vitamin D), and cIMT of common carotid arteries. Results: In the group of patients with T1D and HD(+), significantly higher BMI was found: 23.3 ± 4.4 vs. 21.28 ± 2.9 in group HD(-) and 19.65 ± 2.4 kg/m² in group C (p = 0.003), and higher waist circumference: 79 ± 10.9 vs. 75.10 ± 7.6 in group HD(-) vs. 69.0 ± 7.4 cm in group C (p < 0.001). The mean value of HbA₁c was higher in group T1D and HD(+): 8.8% than in group HD(-): 8.1% (p = 0.04). Significantly higher concentration of hsCRP and lower vitamin D were observed in T1D and HD(+) in comparison to T1D and HD(-) and the control group. The IMT index in the HD(+) group was 0.46 ± 0.05 mm and was comparable to the HD(-) group but significantly higher than in healthy controls: 0.41 ± 0.03 mm (P < 0.05). Conclusions: Young patients with type 1 diabetes mellitus and with coexisting Hashimoto's thyroiditis have a higher BMI, a higher waist circumference, and a higher HbA₁c value, which altogether may cause faster development of macroangiopathy in the near future. Additional risk for cardiovascular disease may result from low vitamin D and increased hsCRP concentration in this group of patients. Coexistence of Hashimoto's thyroiditis did not significantly affect the cIMT value in the studied population.

Epigenetics Predicts Serum 25-Hydroxyvitamin D Response to Vitamin D3 Supplementation in African Americans

SCOPE

The effects of vitamin D₃ supplementations on circulating 25-hydroxyvitamin D [25(OH)D] are varied. The hypothesis that the baseline DNA methylation plays a role in the serum 25(OH)D response to vitamin D₃ supplementation is tested.

METHODS AND RESULTS

A randomized clinical trial is first conducted among 64 African Americans, who are randomly assigned to a placebo or a 16-week treatment of 600, 2000, and 4000 IU d^-1 of vitamin D₃ supplements. Expected serum 25(OH)D concentrations at posttest are estimated by intervention, age, gender, body mass index, baseline 25(OH)D concentrations, and seasonal variations. The 25(OH)D response is categorized into a high-response group when the actual 25(OH)D concentrations at posttest are higher than expected, and a low-response group otherwise. The 25(OH)D response is associated with baseline methylation levels of CYP family and VDR genes (raw p < 0.05). At a genome-wide level, the baseline methylation level of cg07873128 (OSBPL5) that regulates cholesterol balance and calcium homeostasis is higher in the low-response group (false discovery rate = 0.028).

CONCLUSIONS

The baseline methylation levels of CYP family and VDR modulate 25(OH)D response. In addition, the hypermethylation of cg07873128 at the baseline, which is located in the imprinted gene OSBPL5, may reduce the serum 25(OH)D response to vitamin D₃ supplementation.

Role of pregnancy and obesity on vitamin D status, transport, and metabolism in baboons

Human studies show that obesity is associated with vitamin D insufficiency, which contributes to obesity-related disorders. Our aim was to elucidate the regulation of vitamin D during pregnancy and obesity in a nonhuman primate species. We studied lean and obese nonpregnant and pregnant baboons. Plasma 25-hydroxy vitamin D (25-OH-D) and 1α,25-(OH)2-D metabolites were analyzed using ELISA. Vitamin D-related gene expression was studied in maternal kidney, liver, subcutaneous fat, and placental tissue using real-time PCR and immunoblotting. Pregnancy was associated with an increase in plasma bioactive vitamin D levels compared with nonpregnant baboons in both lean and obese groups. Pregnant baboons had lower renal 24-hydroxylase CYP24A1 protein and chromatin-bound vitamin D receptor (VDR) than nonpregnant baboons. In contrast, pregnancy upregulated the expression of CYP24A1 and VDR in subcutaneous adipose tissue. Obesity decreased vitamin D status in pregnant baboons (162 ± 17 vs. 235 ± 28 nM for 25-OH-D, 671 ± 12 vs. 710 ± 10 pM for 1α,25-(OH)2-D; obese vs. lean pregnant baboons, P < 0.05). Lower vitamin D status correlated with decreased maternal renal expression of the vitamin D transporter cubulin and the 1α-hydroxylase CYP27B1. Maternal obesity also induced placental downregulation of the transporter megalin (LRP2), CYP27B1, the 25-hydroxylase CYP2J2, and VDR. We conclude that baboons represent a novel species to evaluate vitamin D regulation. Both pregnancy and obesity altered vitamin D status. Obesity-induced downregulation of vitamin D transport and bioactivation genes are novel mechanisms of obesity-induced vitamin D regulation.

Calcitriol combined with calcium chloride causes apoptosis in undifferentiated adipose tissue-derived human mesenchymal stem cells, but this effect decreases during adipogenic differentiation

Calcitriol, the bioactive hormone of vitamin D, is currently linked to several diseases, such as obesity and gain of adipose mass, due to its liposolubility and, consequently, its sequestration by adipocytes. As rates of obesity continue to increase, research on the biology of weight gain should be encouraged. This study evaluated the effects of calcitriol combined with CaCl₂ on adipose tissue-derived human mesenchymal stem cells. We evaluated the cytotoxicity of the combination by MTT assays, in which undifferentiated cells and cells undergoing adipogenic differentiation were tested for 7 and 14 days. The results demonstrated that the combination of calcitriol at the IC₅₀ and CaCl₂ at the IC₂₀ was effective at reducing the viability of mesenchymal stem cells, but with the progression of cell differentiation towards adipocytes, cell resistance to the cytotoxic effects increased. The percentages of dead cells were 88.29, 57.45 and 28.81% for undifferentiated cells and cells exposed to differentiation medium for 7 and 14 days, respectively. Undifferentiated cells were evaluated for apoptosis in response to the same combination using Annexin V assays, and a possible onset of programmed cell death in undifferentiated cells was detected. Additionally, the combination of the compounds altered the membrane permeability of undifferentiated cells by 16 percentage points and induced cell cycle arrest in S phase due to the accumulation of damage. An evaluation of gene expression revealed the overexpression of the GADD45 and ATM genes and the underexpression of the P21, P53, ATR, BCL-2, EIF2 AK3, IGF1R, DNAse-2, ATF, MAP3K4, ENGO-G, CASP3, CASP7 and CASP8 genes. Our results provide valuable insights into the biology of obesity and may contribute to the development of new anti-obesity therapies focusing on the inhibition of adipose tissue mesenchymal stem cell hyperplasia and adipogenic differentiation.

Relationship between adipose tissue dysfunction, vitamin D deficiency and the pathogenesis of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. Its pathogenesis is complex and not yet fully understood. Over the years many studies have proposed various pathophysiological hypotheses, among which the currently most widely accepted is the "multiple parallel hits" theory. According to this model, lipid accumulation in the hepatocytes and insulin resistance increase the vulnerability of the liver to many factors that act in a coordinated and cooperative manner to promote hepatic injury, inflammation and fibrosis. Among these factors, adipose tissue dysfunction and subsequent chronic low grade inflammation play a crucial role. Recent studies have shown that vitamin D exerts an immune-regulating action on adipose tissue, and the growing wealth of epidemiological data is demonstrating that hypovitaminosis D is associated with both obesity and NAFLD. Furthermore, given the strong association between these conditions, current findings suggest that vitamin D may be involved in the relationship between adipose tissue dysfunction and NAFLD. The purpose of this review is to provide an overview of recent advances in the pathogenesis of NAFLD in relation to adipose tissue dysfunction, and in the pathophysiology linking vitamin D deficiency with NAFLD and adiposity, together with an overview of the evidence available on the clinical utility of vitamin D supplementation in cases of NAFLD.

Causal Effect of Genetic Variants Associated With Body Mass Index on Multiple Sclerosis Susceptibility

Multiple sclerosis (MS) is an autoimmune disease with both genetic and environmental risk factors. Recent studies indicate that childhood and adolescent obesity double the risk of MS, but this association may reflect unmeasured confounders rather than causal effects of obesity. We used separate-sample Mendelian randomization to estimate the causal effect of body mass index (BMI) on susceptibility to MS. Using data from non-Hispanic white members of the Kaiser Permanente Medical Care Plan of Northern California (KPNC) (2006-2014; 1,104 cases of MS and 10,536 controls) and a replication data set from Sweden (the Epidemiological Investigation of MS (EIMS) and the Genes and Environment in MS (GEMS) studies, 2005-2013; 5,133 MS cases and 4,718 controls), we constructed a weighted genetic risk score using 97 variants previously established to predict BMI. Results were adjusted for birth year, sex, education, smoking status, ancestry, and genetic predictors of MS. Estimates in KPNC and Swedish data sets suggested that higher genetically induced BMI predicted greater susceptibility to MS (odds ratio = 1.13, 95% confidence interval: 1.04, 1.22 for the KPNC sample; odds ratio = 1.09, 95% confidence interval: 1.03, 1.15 for the Swedish sample). Although the mechanism remains unclear, to our knowledge, these findings support a causal effect of increased BMI on susceptibility to MS for the first time, and they suggest a role for inflammatory pathways that characterize both obesity and the MS disease process.

Association between Obesity and Serum 25(OH)D Concentrations in Older Mexican Adults

Background: Vitamin D is essential for maintaining bone mineralization and calcium homeostasis, and prevents falls and fractures in older adults. Mexico is undergoing an epidemiologic and demographic transition with increasing obesity rates. The study’s aim was to determine the association of obesity with serum 25-hydroxyvitamin D [25(OH)D] concentrations in older Mexican adults. Methods: Data from 1772 Mexicans, aged ≥50 years, enrolled in a sub-sample of the 3rd wave of the Mexican Health and Aging Study, were included. Serum 25(OH)D concentrations were used to define vitamin D status, and were categorized into tertiles. Body mass index measures were used to categorize older adults into under/normal weight, overweight, and obese groups. Multinomial logistic regression models were used to assess the relationship, adjusting for potential confounders. Results: Approximately 40% and 37% of older Mexican adults were either overweight or obese, respectively. Compared to under/normal weight older Mexicans, obese adults were 1.78 times (95% Confidence Interval (CI) 1.27–2.48) and 1.94 times (95% CI 1.40–2.68) more associated with the first and second tertile concentrations of serum 25(OH)D, respectively. Overweight adults were 1.52 times (95% CI 1.12–2.06) more associated with the second tertile of serum 25(OH)D concentration than under/normal weight adults. Conclusion: Overweight/Obesity was found to be significantly associated with low concentrations of serum 25(OH) in older Mexican adults.

A study of bone turnover markers in gestational diabetes mellitus

INTRODUCTION

Gestational diabetes is defined as carbohydrate intolerance resulting in hyperglycemia of variable severity with the first recognition during pregnancy. Established risk factors for gestational diabetes mellitus (GDM) are maternal age, obesity, family history of diabetes, etc. Vitamin D, parathyroid hormone (PTH), and various other hormones are known for their function in maintaining calcium and phosphorous homeostatic. Furthermore, Vitamin D, PTH serum ionized calcium, and alkaline phosphatase (ALP) have been reported to be altered with glucose homeostasis. The present study compares the bone markers in pregnant women with and without gestational diabetes.

MATERIALS AND METHODS

This cross-sectional study was conducted at outpatient antenatal check-up clinic and outpatient diabetic clinics at J. N. Medical College and Hospital, Aligarh. One hundred pregnant females, of which fifty with GDM and fifty without GDM, were included in the study from January 2014 to November 2015. Detailed history, physical examination, and anthropometric measurement were done. Bone turnover markers in the form of Vitamin D, parathyroid hormone, serum ionized calcium, and serum ALP were measured in pregnant women who had gestational diabetes which was compared with normal pregnant women.

RESULTS

In our study, the mean age of participate of GDM group was 28.2 ± 3 years, while the mean age group in non-GDM group was 25.44 ± 2.78 years. Ionized calcium in GDM was found to be 4.606 ± 0.354 mEq/L, while in non-GDM, it was 4.548 ± 0.384 mEq/L, P = 0.430. Vitamin D came out to be 21.80 ± 9.48 ng/ml, while it was 32.346 ± 8.37 ng/ml in non-GDM group. Serum PTH in GDM group was 71.436 ± 36.189 pg/ml and 37.168 ± 8.128 pg/ml in nondiabetic gestational group. Serum ALP in GDM group was 9.1 ± 4.56 KA U/dl and 6.98 ± 2.2 KA U/dl in nondiabetic gestational group, P - 0.0038. In GDM group, there was a significant negative linear correlation between PTH and 25-hydroxyvitamin D with research correlation coefficient r = -0.9073, P = 0; there was a significant positive linear correlation coefficient between PTH and ALP with Persian correlation coefficient r = 0.6597, P = 0; there was no statistically significant correlation between PTH and ionized calcium r = 0.1416, P = 0.3267.

CONCLUSION

All GDM subjects should ideally be screened for serum calcium, vitamin D, PTH, ALP. If found impaired should immediately be corrected in order to prevent its adverse effects on maternal and fetal outcome. Vitamin D supplementation should ideally be initiated in all GDM females even if the above parameters are not investigated in Indian setup.

Is vitamin D testing at a tertiary referral hospital consistent with guideline recommendations?

To determine if 25 hydroxyvitamin D (25OHD) testing at our tertiary referral hospital is consistent with guideline recommendations concerning the clinical indications for testing, the timing of repeat testing and utilisation of the test result, we conducted a retrospective audit of electronic laboratory and patient case records. We included adult inpatients and outpatients who had serum 25OHD measured during a randomly selected one-week audit period and who had patient case records available for detailed review. The audit sample comprised 184 serum 25OHD measurements (134 initial and 50 repeat tests). There were 81 (60%) initial and 15 (30%) repeat tests [96 (52%) overall] that were consistent with guideline recommendations concerning clinical indication, timing of repeat testing and utilisation of result. Almost half the 25 hydroxyvitamin D tests audited were potentially unnecessary and/or not utilised clinically. Improved adherence to guideline recommendations for 25 hydroxyvitamin D testing, utilisation of test results and enforcement of new indications for testing due to be introduced by Medicare Australia could result in significant cost savings without adversely affecting patient outcomes.

Vitamin D [1,25(OH)2D3] Differentially Regulates Human Innate Cytokine Responses to Bacterial versus Viral Pattern Recognition Receptor Stimuli

Vitamin D plays multiple roles in regulation of protective and maladaptive immunity. Although epidemiologic studies link poor in vivo 25(OH)D status to increased viral respiratory infections, we poorly understand how vitamin D affects viral pattern recognition receptor (PRR)-driven cytokine production. In this study, we hypothesized that the biologically active metabolite of vitamin D, 1,25(OH)2D3, inhibits human proinflammatory and anti-inflammatory innate cytokine responses stimulated by representative bacterial or viral PRR ligands. Fresh PBMCs or CD14(+) monocytes were stimulated with TLR4, TLR7/8-selective ligands, or respiratory syncytial virus (RSV) ± 1,25(OH)2D3. Proinflammatory and anti-inflammatory responses resulting from TLR4 stimulation were inhibited ∼50% in the presence of 1,25(OH)2D3. Conversely, its usage at physiologic through pharmacologic concentrations inhibited neither proinflammatory nor anti-inflammatory responses evoked by viral PRR ligands or infectious RSV. This differential responsiveness was attributed to the finding that TLR7/8, but not TLR4, stimulation markedly inhibited vitamin D receptor mRNA and protein expression, selectively reducing the sensitivity of viral PRR responses to modulation. 1,25(OH)2D3 also enhanced expression of IkBa, a potent negative regulator of NF-κB and cytokine production, in TLR4-stimulated monocytes while not doing so upon TLR7/8 stimulation. Thus, 1,25(OH)2D3 inhibits both proinflammatory and a broad panel of anti-inflammatory responses elicited by TLR4 stimulation, arguing that the common view of it as an anti-inflammatory immune response modifier is an oversimplification. In viral responses, it consistently fails to modify TLR7/8- or RSV-stimulated innate cytokine production, even at supraphysiologic concentrations. Collectively, the data call into question the rationale for increasingly widespread self-medication with vitamin D supplements.

Influence of obesity on vertebral fracture prevalence and vitamin D status in postmenopausal women

Background

It is well established that weight is an important determinant of bone health. Whereas obesity is associated with increased mortality and morbidity from diabetes and cardiovascular diseases, high body weight is widely believed to be associated to hypovitaminosis D and protective against the development of osteoporosis and fracture risk. The objective of the study was to evaluate the effect of BMI on vitamin D status and on densitometric vertebral fractures (VFs) in a large series of asymptomatic women aged over 50 who had a VFA examination during their bone mineral density (BMD) testing.

Methods

We enrolled 429 postmenopausal women (mean age, weight and BMI of 59.5 ± 8.3 (50 to 83) years, 75.8 ± 13.3 (35 to 165) kgs and 29.9 ± 5.2 (14.6 to 50.8) kg/m², respectively. Lateral VFA images and scans of the lumbar spine and proximal femur were obtained using a Lunar Prodigy densitometer. VFs were defined using the Genant semiquantitative (SQ) approach. Clinical risk factors of osteoporosis were collected and 25-hydroxivitamin D was measured using electrochimiluminescence (Roche).

Results

Prevalence of osteoporosis and hypovitaminosis D (<20 ng/ml) was 21.0 % and 78.1 % respectively. VFs grade 2/3were identified in 76 (17.7 %). Comparison between women according to their BMI showed that obese women had a higher BMD and less proportion of women with osteoporosis and VFs grade 2/3 than lean and overweight women. The prevalence of VFs globally increased with age and as BMI and BMD declined. Stepwise regression analysis showed that the presence of osteoporosis was independently related to BMI and history of fractures while the presence of grade 2/3 VFs was independently related to age, hypovitaminosis D and years of menopause.

Conclusion

Obese women had a higher BMD and lower prevalence of VFs. VFs were significantly related to age, hypovitaminosis D and years since menopause. However, among obese women, prevalence of VFs was increased in osteoporotic women.

The relationship between low maternal serum vitamin D levels and glycemic control in gestational diabetes assessed by HbA1c levels: an observational cross-sectional study

Background

A great association between vitamin D deficiency and type 2 diabetes mellitus has been suggested in literature. During pregnancy, this deficiency is even more critical. It appears that vitamin D insufficiency during pregnancy may be associated with maternal hazards. The aim of this study was to assess the relation between the levels of 25-hydroxy-cholecalciferol (vitamin D), and the glycemic control in pregnant women.

Methods

An observational cross-section study including 160 pregnant women between 20-40 years in age, in their third trimester, divided into two equal groups. First group consisted of 80 women with established diagnosis of gestational diabetes and the second group with proved normal blood glucose levels. We assessed vitamin D in serum, fasting blood glucose, serum insulin and glycosylated hemoglobin (HbA1c) levels and we depicted the insulin sensitivity using the Quantitative insulin sensitivity check index (Quicki). The results were collected and statistically correlated.

Results

The mean vitamin D levels were 46.61 ± 6.087 and 47.25 ± 10.181in controls and women with gestational diabetes mellitus (GDM) respectively. The fasting insulin levels were significantly higher in the group with GDM with a mean of 18.51 ± 6.44 compared to 8.95 ± 2.52 in the control group.

The correlation coefficient (r) between HbA1c levels and Vitamin D level was -0.492 with a P value <0.05. Similar associations were also found with the fasting blood sugar levels (r = - 0.386) and with Quicki values (r = -0.250). Vitamin D levels correlated significantly with the fasting blood glucose, the fasting serum insulin and the HbA1c levels, the P value in all these correlations were <0.05. The P value with Quicki results was 0.064.

Conclusions

There is a statistically significant negative correlation between the glycemic control and vitamin D levels in serum in the whole study population. The effect of adequate vitamin D replacement on glycemic control was not studied in our work correlation. We suggest larger scale studies addressing this issue.