title: Vitamin D and C-Reactive Protein: A Mendelian Randomization Study Baseline Serum 25-Hydroxy Vitamin D Is Predictive of Future Glycemic Status and Insulin Resistance Serum vitamin-D predicts insulin resistance in individuals with prediabetes Multivariate Path Analysis of Serum 25-Hydroxyvitamin D Concentration, Inflammation, and Risk of Type 2 Diabetes Mellitus Impact of dietary and lifestyle on vitamin D in healthy student girls aged 11-15 years. Plasma vitamin D is associated with fasting insulin and homeostatic model assessment of insulin resistance in young adult males, but not females, of the Jerusalem Perinatal Study. Cardiorespiratory fitness, adiposity, and serum 25-dihydroxyvitamin D levels in women: the Cooper Center Longitudinal Study. Vitamin D status in relation to obesity, bone mineral density, bone turnover markers and vitamin D receptor genotypes in healthy Saudi pre- and postmenopausal women Associations between 25-hydroxyvitamin D and weight gain in elderly women. Serum 25-hydroxyvitamin D level and diabetic nephropathy in patients with type 2 diabetes mellitus Association of vitamin D deficiency with incidence of type 2 diabetes in high-risk Asian subjects. Cross-talk between muscle and bone in postmenopausal women with hypovitaminosis D Effects of weight loss on serum vitamin D in postmenopausal women. The serum 25-hydroxyvitamin D response to vitamin D supplementation is related to genetic factors, BMI, and baseline levels.
abstract: Vitamin D deficiency is widely prevalent and has been associated with many diseases . It has been suggested that vitamin D has effects on the immune system and inhibits inflammation . The aim of our study was to investigate whether vitamin D has an inhibitory effect on systemic inflammation by assessing the association between serum levels of vitamin D and C-reactive protein . We studied the association between serum 25-hydroxyvitamin D and C-reactive protein through linear regression in 9,649 participants of the Rotterdam Study , an observational , prospect i ve population -based cohort study . We used genetic variants related to vitamin D and CRP to compute a genetic risk score and perform bi-directional Mendelian r and omization analysis . In linear regression adjusted for age , sex , cohort and other confounders , natural log-transformed CRP decreased with 0.06 ( 95 % CI : -0.08 , -0.03 ) unit per st and ard deviation increase in 25-hydroxyvitamin D. Bi-directional Mendelian r and omization analyses showed no association between the vitamin D genetic risk score and lnCRP ( Beta per SD = -0.018 ; p = 0.082 ) or the CRP genetic risk score and 25-hydroxyvitamin D ( Beta per SD = 0.001 ; p = 0.998 ) . In conclusion , higher levels of Vitamin D are associated with lower levels of C-reactive protein . In this study we did not find evidence for this to be the result of a causal relationship OBJECTIVE —Accumulating epidemiological evidence suggests that hypovitaminosis D may be associated with type 2 diabetes and related metabolic risks . However , prospect i ve data using the biomarker serum 25-hydroxyvitamin D [ 25(OH)D ] are limited and therefore examined in the present study . RESEARCH DESIGN AND METHODS —A total of 524 r and omly selected nondiabetic men and women , aged 40–69 years at baseline , with measurements for serum 25(OH)D and IGF-1 in the population -based Ely Study , had glycemic status ( oral glucose tolerance ) , lipids , insulin , anthropometry , and blood pressure measured and metabolic syndrome risk ( metabolic syndrome z score ) derived at baseline and at 10 years of follow-up . RESULTS —Age-adjusted baseline mean serum 25(OH)D was greater in men ( 64.5 nmol/l [ 95 % CI 61.2–67.9 ] ) than women ( 57.2 nmol/l [ 54.4,60.0 ] ) and varied with season ( highest late summer ) . Baseline 25(OH)D was associated inversely with 10-year risk of hyperglycemia ( fasting glucose : β = −0.0023 , P = 0.019 ; 2-h glucose : β = −0.0097 , P = 0.006 ) , insulin resistance ( fasting insulin β = −0.1467 , P = 0.010 ; homeostasis model assessment of insulin resistance [ HOMA-IR ] : β = −0.0059 , P = 0.005 ) , and metabolic syndrome z score ( β = −0.0016 , P = 0.048 ) after adjustment for age , sex , smoking , BMI , season , and baseline value of each metabolic outcome variable . Associations with 2-h glucose , insulin , and HOMA-IR remained significant after further adjustment for IGF-1 , parathyroid hormone , calcium , physical activity , and social class . CONCLUSIONS —This prospect i ve study reports inverse associations between baseline serum 25(OH)D and future glycemia and insulin resistance . These associations are potentially important in underst and ing the etiology of abnormal glucose metabolism and warrant investigation in larger , specifically design ed prospect i ve studies and r and omized controlled trials of supplementation Background & objectives : Patients with diabetes and vitamin-D insufficiency have increased insulin resistance . Similar observations among individuals with prediabetes are not well documented . The aim of this study was to find the occurrence of vitamin-D insufficiency/deficiency among individuals with prediabetes and to evaluate the relationship between vitamin-D status and insulin resistance . Methods : One hundred fifty seven individuals with prediabetes who fulfilled all the inclusion and exclusion criteria underwent clinical examination , anthropometric measurements ( waist circumference , waist-hip ratio , waist-height ratio ) and blood sampling after overnight fast for estimation of fasting blood glucose , fasting insulin , 25(OH)vitamin-D , intact parathyroid hormone ( iPTH ) and lipid profile . One hour post 75 g glucose ( 1hPG ) blood glucose during oral glucose tolerance test was measured . Results : Vitamin-D deficiency/insufficiency was found in 115 ( 73.25 % ) individuals with prediabetes .  Severe vitamin-D deficiency ( < 10 ng/ml ) was seen in 14.65 per cent individuals . Individuals with the lowest vitamin-D levels ( < 10 ng/ml ) had the highest insulin resistance ( HOMA2-IR : 2.04 ± 0.67 ) . Serum 25(OH)D had a statistically significant inverse correlation with insulin resistance ( HOMA2-IR ; r=-0.33 ; P=0.008 ) , and positive correlation with insulin sensitivity ( QUICKI ; r=0.39 ; P=0.002 ) , after adjusting for BMI and HbA1c . There was no correlation between vitamin-D status and estimated beta cell mass ( HOMA-β ) . The mean waist-height ratio among individuals with prediabetes was 0.57 ( normal<0.5 ) indicating a high risk of cardiovascular morbidity . Individuals with elevated 1hPG>155 mg/dl had significantly higher BMI and worse insulin resistance , and 1hPG correlated well with 2 hour post glucose blood glucose ( r=0.57 ; P<0.001 ) . Interpretations & conclusions : Vitamin-D deficiency/insufficiency may have some role in the development/worsening of insulin resistance in individuals with prediabetes in our country who have a high cardiovascular risk . Prospect i ve studies on a large group of individuals need to be done to confirm the findings Background and Aims . Despite growing interest in the protective role that vitamin D may have in health outcomes , little research has examined the mechanisms underlying this role . This study aim ed to test two hypotheses : ( 1 ) serum 25-hydroxyvitamin D [ 25(OH)D ] is inversely associated with type 2 diabetes mellitus ( T2DM ) and elevated hemoglobin A1c ; ( 2 ) these associations are mediated by serum C-reactive protein ( CRP ) . Methods . Participants aged 20 and older in 2001–2006 National Health and Nutrition Examination Surveys ( n = 8,655 ) with measures of serum 25(OH)D , CRP , hemoglobin A1c , and other important covariates were included in the present study . Logistic regression and path analysis methods were applied to test the study hypotheses . Results . Decreased serum 25(OH)D concentration was significantly associated with increased odds of T2DM .  In males , an estimated 14.9 % of the association between 25(OH)D and hemoglobin A1c was mediated by serum CRP . However , this mediation effect was not observed in females . Conclusion . Using a nationally representative sample , the present study extends previous research and provides new evidence that the effect of  decreased serum vitamin D concentration on T2DM may proceed through increased systemic inflammation in males . Longitudinal studies and r and omized control trials are needed to confirm the present findings OBJECTIVE To study daily intake of calcium , phosphorus and vitamin D , to determine the biochemical findings of rickets and the effect of sunlight exposure and vitamin D supplementation in school girls with hypovitaminosis D. METHODS A cross-sectional study was conducted on school girls aged 11 - 15 years selected r and omly from various areas of Tehran , Iran .  Dietary information and amount of sunlight exposure were estimated by a 7 day recalling method using self-reported question naire . Hypovitaminosis D defined as low serum 25-hydroxyvitamin D concentration with two or more others abnormal biochemical findings . Girls with hypovitaminoses D were r and omly divided into two groups . The faces and h and s of girls in group 1 were exposed to sunlight for one hour per day for twenty days , while those in group 2 were administered vitamin D capsules , 50,000 IU per day for the same period . RESULTS four-hundred fourteen girls evaluated , mean daily calcium intake , sunlight exposure and vitamin D acquirement were 360 mg , 10 minutes and 119 IU , respectively . Mean serum 25-hydroxyvitamin D concentration was 30 ng/ml among all girls whereas in 15 ( 3.63 % ) of 414 girls was 7.8 ng/ml . Abnormal biochemical findings in these girls included hypocalcemia ( n=4 ) , hypophosphatemia ( n=5 ) , raised serum alkaline phosphatase ( n=13 ) , and parathyroid hormone ( n=15 ) . After intervention , mean serum 25-hydroxyvitamin D concentration  in sunlight exposure ( n=8 ) and vitamin D ( n=7 ) supplementation increased to 14.4+/-4 ng/ml and 23+/-4 ng/ml respectively . There was a significant difference between the two groups ( p<0.05 ) . CONCLUSION Vitamin D deficiency developed in rapid growth period of girls without clear clinical rickets in sunny temperate climate city in Iran which vitamin D supplementation improved biochemical findings better than sunlight exposure OBJECTIVE To examine cross-sectional relationships between plasma vitamin D and cardiometabolic risk factors in young adults . DESIGN Data were collected from interviews , physical examinations and biomarker measurements . Total plasma 25-hydroxyvitamin D ( 25(OH)D ) was measured using LC-t and em MS . Associations between 25(OH)D and cardiometabolic risk factors were modelled using weighted linear regression with robust estimates of st and ard errors . SETTING Individuals born in Jerusalem during 1974 - 1976 . SUBJECTS Participants of the Jerusalem Perinatal Study ( n 1204 ) interviewed and examined at age 32 years . Participants were over sample d for low and high birth weight and for maternal pre-pregnancy obesity .  RESULTS Mean total 25(OH)D concentration among participants was 21·7 ( sd 8·9 ) ng/ml . Among males , 25(OH)D was associated with homeostatic model assessment of insulin resistance ( natural log-transformed , β=-0·011 , P=0·004 ) after adjustment for BMI . However , these associations were not present among females ( P for sex interaction=0·005 ) . CONCLUSIONS We found evidence for inverse associations of 25(OH)D with markers of insulin resistance among males , but not females , in a healthy , young adult Caucasian population . Prospect i ve studies and studies conducted on other population s investigating sex-specific effects of vitamin D on cardiometabolic risk factors are warranted PURPOSE We examined the cross-sectional associations among cardiorespiratory fitness ( CRF ) , different measures of adiposity , and serum vitamin D levels in women . METHODS Between 2007 and 2010 , 1320 women completed a health examination . Measures included body mass index ( BMI ) , waist circumference ( WC ) , waist/hip ratio , percent body fat , CRF based on a maximal treadmill exercise test , and measurement of serum vitamin D.  Participants were classified by CRF as unfit ( lowest 20 % ) and fit ( remaining 80 % ) based on age , as well as by clinical cutoff points for adiposity measures , and by categories of serum vitamin D. We examined trends of CRF and adiposity exposures across serum vitamin D categories . We calculated odds ratios ( OR ) of serum vitamin D insufficiency or deficiency across levels of adiposity exposures before and after adjustment for CRF . RESULTS We observed a significant positive trend for CRF across incremental serum vitamin D categories ( p<0.001 ) . When compared to ORs for normal weight women , ORs for serum vitamin D insufficiency or deficiency were significantly higher for overweight women within each adiposity exposure ( p<0.05 ) . When grouped into categories of fit and unfit ( upper 80 % and lower 20 % of CRF distribution , respectively ) ,  serum vitamin D  was significantly lower in unfit than in fit women within each stratum of WC and waist/hip ratio and within the normal weight BMI stratum . CONCLUSIONS Serum vitamin D levels are positively associated with CRF and negatively associated with different measures of adiposity in women . Higher CRF attenuates the relationship between adiposity level and serum vitamin D. Future prospect i ve studies are warranted Summary The various factors that may contribute to vitamin D deficiency or insufficiency were examined among healthy Saudi pre- and postmenopausal women .  Vitamin D deficiency was highly prevalent among studied Saudi women with obesity , poor sunlight exposure , poor dietary vitamin D supplementation and age as the main risk factors . Introduction The various factors that may contribute to vitamin D deficiency or insufficiency in relation to bone health among Saudi women are not known . The main objectives of the present study were to determine the factors influencing  vitamin D status in relation to serum 25-hydroxyvitamin D ( 25(OH)D ) , intact parathyroid hormone ( PTH ) , bone turnover markers ( BTMs ) , bone mineral density ( BMD ) , and vitamin D receptor genotype ( VDR ) in healthy Saudi pre- and postmenopausal women . Methods A total number of 1,172 healthy Saudi women living in the Jeddah area were r and omly selected and studied .  Anthropometric parameters , socioeconomic status , sun exposure index together with serum levels of 25(OH)D , calcitriol , intact PTH , Ca , PO4 , Mg , creatinine , albumin , and biochemical BTMs were measured . BMD was measured by a dual energy X-ray absorptiometry and VDR genotypes were also determined . Results About 80.0 % of Saudi women studied exhibited vitamin D deficiency ( serum 25(OH)D < 50.0 nmol/L ) with only 11.8 % of all women were considered with adequate vitamin D status ( serum 25(OH)D > 75 nmol/L ) . Secondary hyperparathyroidism was evident in 18.5 % and 24.6 % in pre- and postmenopausal women with 25(OH)D < 50 nmol/L. Serum 25(OH)D was lower ( P < 0.001 ) and intact PTH higher ( P < 0.001 ) in the upper quintiles of body mass index ( BMI ) and waist-to-hip ratio ( WHR ) . Multiple linear regression analysis showed that BMI , sun exposure index , poor dietary vitamin D supplementation , WHR , and age were independent positive predictors of serum 25(OH)D values . Conclusions Vitamin D deficiency is highly prevalent among healthy Saudi pre- and postmenopausal women and largely attributed to obesity , poor exposure to sunlight , poor dietary vitamin D supplementation , and age BACKGROUND 25-Hydroxyvitamin D [ 25(OH)D ] levels are lower in obese individuals . Determining whether low vitamin D status can predispose weight gain requires a longitudinal study . METHODS From a community-based multicenter U.S. prospect i ve cohort of 9704 ( Study of Osteoporotic Fractures [ SOF ] ) , 4659 women aged ≥65 with baseline 25(OH)D measurement were followed for 4.5 years . They were weighed at baseline and follow-up visits , and a subset ( n=1054 ) had 25(OH)D levels remeasured at follow-up . RESULTS Women with 25(OH)D levels ≥30 ng/mL had lower baseline weight ( 141.6 pounds ) compared to women with 25(OH)D levels < 30 ng/mL ( 148.6 pounds ) ( p<0.001 ) . Overall , 25(OH)D status was not associated with weight change over 4.5 years , although there was a significant interaction between 25(OH)D status and weight change category ( loss , gain , stable ) ( p<0.0001 ) . In women who gained ≥5 % weight , those with baseline 25(OH)D levels ≥30 ng/mL gained 16.4 pounds ( 12.2 % of baseline weight ) over 4.5 years compared to 18.5 pounds ( 13.9 % of baseline weight ) in women with levels < 30 ng/mL ( p=0.04 ) . In women who lost ≥5 % weight or remained stable ( < 5 % weight change ) , there was no association between 25(OH)D status at baseline and weight change . Among women who gained weight and had 25(OH)D measured at both visits , having sustained or developing 25(OH)D levels ≥30 ng/mL was associated with less weight gain between visits ( 14.81 vs. 16.34 pounds , p=0.04 ) . CONCLUSIONS Higher 25(OH)D levels are associated with lower weight gains , suggesting low vitamin D status may predispose to fat accumulation Abstract Objective Patients with chronic kidney disease have a very high prevalence of deficiency of 25-hydroxyvitamin D [ 25(OH)D ] . We evaluate the association between 25(OH)D and diabetic nephropathy ( DN ) in a Chinese sample with type 2 diabetes mellitus . Method The subjects were patients with diabetes mellitus who were hospitalized at our hospital during the period from June 2012 to July 2014 .  Serum levels of 25(OH)D were tested at admission . DN was defined as a urinary albumin-to-creatinine ratio ≥30 mg/g in a r and om spot urine sample . Multivariate analyses were performed using logistic regression models . Results We found that serum 25(OH)D levels were significantly lower in diabetes with DN as compared to without DN [ 8.5 ( IQR 6.8–11.3 ) vs. 13.9 ( IQR 11.2–18.2 ) ng/ml , P < 0.0001 ] . Based on the ROC curve , the optimal cutoff value of serum 25(OH)D levels as an indicator for diagnosis of DN was projected to be 10.5 ng/ml , which yielded a sensitivity of 82.6 % and a specificity of 72.7 % , with the area under the curve at 0.807 [ 95 % confidence interval ( CI ) 0.764–0.849 ] . Multivariate logistic regression analysis adjusted for common risk factors showed that with serum 25(OH)D level ≤10.5 ng/ml was an independent indicator of DN [ odds ratio ( OR ) = 6.559 ; 95 % CI 2.864–11.368 ] . Conclusions Our findings suggested that diabetes with DN had lower serum 25(OH)D levels and that determination of 25(OH)D statuses might be used to identify patients at increased risk of developing nephropathy complications BACKGROUND Recent studies suggest an association between 25-hydroxyvitamin D [ 25(OH)D ] and type 2 diabetes ( T2D ) risk . However , prospect i ve studies investigating the relation between vitamin D inadequacy and incidence of T2D incorporating obesity and dynamic measures of insulin resistance ( IR ) and pancreatic β cell function are limited . OBJECTIVE We tested the hypothesis that baseline 25(OH)D is associated with the incidence of T2D in high-risk subjects for up to 5 y of follow-up , independently of obesity , baseline IR , and β cell function . DESIGN We recruited 1080 nondiabetic Korean subjects [ mean ± SD age : 49.5 ± 11.4 y ] based on the presence of one or more risk factors for T2D , including obesity , hypertension , dyslipidemia , and /or family history of T2D . We measured anthropometric and biochemical indicators , HOMA2-IR , and the insulinogenic index ( IGI ; calculated as change in insulin at 30 min/change in glucose at 30 min ) from a 75-g oral-glucose-tolerance test . RESULTS Of the participants , 10.5 % had a serum 25(OH)D deficiency ( < 10 ng/mL ) , 51.6 % had an insufficiency ( 10.0 - 19.9 ng/mL ) , and 38.0 % had a sufficiency ( ≥20 ng/mL ) , and the incidence of T2D at 32.3 ± 15.6 mo ( ±SD ) declined accordingly : 15.9 % , 10.2 % , and 5.4 % , respectively ( P < 0.001 ) . After adjustment for age , sex , blood pressure , lifestyles , family history , season , parathyroid hormone , and high-sensitivity C-reactive protein , the participants with 25(OH)D deficiency had an increased risk of T2D independently of BMI , HOMA2-IR , and IGI ; the HRs were 2.06 ( 95 % CI : 1.22 , 3.49 ) for 25(OH)D 10 - 19.9 ng/mL compared with ≥20 ng/mL and 3.23 ( 95 % CI : 1.66 , 6.30 ) for 25(OH)D < 10 ng/mL compared with ≥20 ng/mL. CONCLUSION The current prospect i ve study suggests that vitamin D metabolism may play a role in T2D pathogenesis independently of known risk factors . This trial was registered at clinical trials.gov as NCT01508481 Abstract Objectives : Visceral fat is more harmful than subcutaneous fat . Women with high amounts of visceral fat have an increased risk of metabolic syndrome ( MetS ) , insulin resistance and low level of serum vitamin D. Methods : This was a prospect i ve , r and omized and controlled study . Postmenopausal women ( n = 101 ) aged 45–70 years were included . The assessed parameters were : body mass index ( BMI ) , waist circumference ( WC ) , 25-hydroxyvitamin D ( 25-OHD ) status , serum insulin and HOMA-IR , bone mineral density , total fat mass , fat mass index ( FMI ) measured by DXA , and muscle strength . Results : Significantly lower values of 25-OHD ( 35.26 ± 1.61 nmol/l ) were found in women with MetS compared to those without MetS ( 47.52 ± 3.47nmol/l ) ( t = 3.699 ; p < 0.000 ) . A significant negative correlation was observed between 25-OHD levels and : WC ( rhoWC = −0.94 ; p < 0.004 ) , BMI ( rho BMI = −0.80 ; p < 0.002 ) , FMI ( rhoFMI = −0.31 ; p < 0.002 ) and impaired fasting glucose ( IFG ) ( rhoIFG = −0.23 ; p < 0.001 ) . The percentage of body fat was statistically significantly higher in the group with insufficient 25-OHD ( 39.6 % ) and in the group with a deficit of 25-OHD ( 48.2 % ) , compared with the maximum permitted percentage body fat of 35 % for a female ( t = −22.63 ; p < 0.002 ) . The average h and grip strength of these moderately obese participants was 27.4 ± 4.7 kg . It was significantly lower than the normative grip strength for referent range groups ( t = −21.65 ; p < 0.001 ) . Conclusion : A low 25-OHD level in postmenopausal women is associated with high body fat , metabolic syndrome , low muscular strength and osteopenia BACKGROUND Low concentrations of circulating vitamin D are common with obesity and may represent a potential mechanism explaining the elevated risk of certain cancers and cardiovascular outcomes observed in individuals who are overweight or obese . OBJECTIVE The objective of this study was to investigate the effects of 12 mo of weight loss through caloric restriction , exercise intervention , or both on serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations . DESIGN Overweight and obese postmenopausal women ( n = 439 ) were r and omly assigned to 1 of 4 groups : 1 ) diet modification ( n = 118 ) , 2 ) exercise ( n = 117 ) , 3 ) diet + exercise ( n = 117 ) , or 4 ) control ( n = 87 ) . The diet intervention was a group-based reduced-calorie program with a 10 % weight-loss goal . The exercise intervention consisted of 45 min of moderate-to-vigorous intensity aerobic activity daily for 5 d/wk . Serum 25(OH)D concentrations were measured by using a competitive chemiluminescent immunoassay at baseline and 12 mo . RESULTS No significant change in serum 25(OH)D was found between the intervention and control groups . Women who lost < 5 % , 5 - 9.9 % , 10 - 14.9 % , or ≥15 % of baseline weight had mean increases in 25(OH)D of 2.1 , 2.7 , 3.3 , and 7.7 ng/mL , respectively ( P for trend = 0.002 ) . Baseline vitamin D status did not modify the effect of the interventions on weight loss or body-composition changes at the 12-mo follow-up . CONCLUSION A greater degree of weight loss , achieved through either a reduced-calorie diet or increased exercise , is associated with increased circulating 25(OH)D concentrations . This trial is registered at clinical trials.gov as NCT00470119 OBJECTIVE The serum 25-hydroxyvitamin D ( 25(OH)D ) level is not only dependent on vitamin D intake and production in the skin but also dependent on genetic factors . Thus , in large genome-wide association studies , it has been shown that single nucleotide polymorphisms ( SNPs ) in the vitamin D binding protein ( DBP ) , as well as in enzymes related to activation or degradation of vitamin D and its metabolites , are as important for the serum 25(OH)D level as the effect of season . How these SNPs affect the serum 25(OH)D response to vitamin D supplementation is uncertain . DESIGN AND METHODS Data were pooled from three r and omized controlled trials where 40 , 000 IU vitamin D/week was given for 6 months . Serum 25(OH)D was measured before and at the end of the intervention , and the subjects were genotyped for SNPs related to the serum 25(OH)D level . RESULTS Baseline 25(OH)D levels were significantly related to SNPs in the DBP and CYP2R1 genes . Those with SNPs associated with the lowest baseline 25(OH)D levels also had the smallest increase ( delta ) after supplementation . Those with the lowest baseline serum 25(OH)D ( without regard to genotypes ) had the highest increase ( delta ) after supplementation . Subjects with high BMI had lowest baseline 25(OH)D levels and also the smallest increase ( delta ) after supplementation . CONCLUSIONS The serum 25(OH)D response to supplementation depends on genes , baseline level , and BMI . However , whether this is clinical ly important or not depends on the therapeutic window of vitamin D , an issue that is still not settled
target: In conclusion , the deficiency of vitamin D is associated with an increased level of BMI in the studies of both diabetic and non-diabetic subjects .
background: The deficiency of vitamin D is prevalent all over the world .
  Studies have shown that vitamin D may play an important role in the development of obesity .
  The current study was conducted to quantitatively evaluate the association between serum 25-(OH ) vitamin D levels  and the risk of obesity in both diabetic and non-diabetic subjects .