Rising serum 25-hydroxy-vitamin D levels after weight loss in obese women correlate with improvement in insulin resistance. Type of dietary fat is associated with the 25-hydroxyvitamin D3 increment in response to vitamin D supplementation. Large Doses of Vitamin D Fail to Increase 25-Hydroxyvitamin D Levels or to Alter Cardiovascular Risk Factors in Obese Adolescents: A Pilot Study. Three doses of vitamin D, bone mineral density, and geometry in older women during modest weight control in a 1-year randomized controlled trial Preliminary data about the influence of vitamin D status on the loss of body fat in young overweight/obese women following two types of hypocaloric diet. Effects of weight loss on serum vitamin D in postmenopausal women. Influence of Calcium and Vitamin D Supplementation on Weight and Fat Loss in Obese Women The Effect of High-Dose Vitamin D Supplementation on Calciotropic Hormones and Bone Mineral Density in Obese Subjects with Low Levels of Circulating 25-Hydroxyvitamin D: Results from a Randomized Controlled Study Vitamin D3 supplementation during weight loss: a double-blind randomized controlled trial. Dairy Foods in a Moderate Energy Restricted Diet Do Not Enhance Central Fat, Weight, and Intra-Abdominal Adipose Tissue Losses nor Reduce Adipocyte Size or Inflammatory Markers in Overweight and Obese Adults: A Controlled Feeding Study Prospective Study of Serum 25-hydroxy Vitamin D and Tooth Loss Supplementation with cholecalciferol does not result in weight reduction in overweight and obese subjects. Cross-sectional and longitudinal relation between serum 25-hydroxyvitamin D and body mass index: the Tromsø study A global study of vitamin D status and parathyroid function in postmenopausal women with osteoporosis: baseline data from the multiple outcomes of raloxifene evaluation clinical trial. One-year treatment of obesity: a randomized, double-blind, placebo-controlled, multicentre study of orlistat, a gastrointestinal lipase inhibitor Dairy calcium intake, serum vitamin D, and successful weight loss. Vitamin D status modification by two slightly hypocaloric diets in young overweight/obese women. Effect of Vitamin D Supplementation on Obesity‐Induced Insulin Resistance: A Double‐Blind, Randomized, Placebo‐Controlled Trial Effects of Vitamin D3 Supplementation on Lean Mass, Muscle Strength, and Bone Mineral Density During Weight Loss: A Double-Blind Randomized Controlled Trial. Increased PTH and 1.25(OH)(2)D levels associated with increased markers of bone turnover following bariatric surgery. Weight loss increases and fat loss decreases all-cause mortality rate: results from two independent cohort studies Milk fortified with the current adequate intake for vitamin D (5 microg) increases serum 25-hydroxyvitamin D compared to control milk but is not sufficient to prevent a seasonal decline in young women. Glucose intolerance is associated with altered calcium homeostasis: a possible link between increased serum calcium concentration and cardiovascular disease mortality.
OBJECTIVE The objective of the study was to examine changes of 25-hydroxy-vitamin D ( 25OHD ) and PTH blood levels 4 and 20 wk after low-calorie diet-induced weight loss . METHODS Forty-four obese women [ aged 40.6 + /- 11.4 yr , body mass index ( BMI ) 36.7 + /- 4.9 kg/m(2 ) ] and 25 controls ( BMI 22.9 + /- 1.5 kg/m(2 ) ) were examined .  Anthropometric and cardiometabolic parameters and 25OHD and PTH levels  were determined at baseline and 4 and 20 wk after a low-calorie diet . RESULTS At baseline , 25OHD levels were lower in obese compared with control subjects ( 17 + /- 6.0 vs. 23.8 + /- 8.7 ng/ml , P < 0.001 ) , whereas no differences were found in PTH levels . In all women , a negative correlation was found between 25OHD levels and body weight ( BW ) ( r -0.32 , P < 0.001 ) , BMI ( r -0.37 , P < 0.001 ) , waist circumference ( r -0.26 , P < 0.05 ) , and percent fat mass ( r -0.38 , P = 0.001 ) as determined by bioelectrical impedance analysis . The 4-wk low-calorie diet ( n = 37 ) reduced BW and led to significant improvements in the homeostasis model assessment ( HOMA ) index and lipid levels . The 20-wk low-calorie diet ( n = 26 ) result ed in reduction of BW and BMI by 10 % , HOMA index ( 4.7 + /- 3.8 vs. 3.10 + /- 1.7 , P < 0.01 ) , and lipids levels ( except high density lipoprotein cholesterol ) and increase in 25OHD ( 15.4 + /- 6.0 vs. 18.3 + /- 5.1 ng/ml , P < 0.05 ) , compared with baseline . PTH levels were unchanged . The increase of 25OHD levels was associated with the reduction of insulin levels and HOMA index ( r -0.43 , P < 0.05 ) . CONCLUSIONS Blood 25OHD levels were low in obese women and correlated inversely with severity measures of obesity . Weight loss of 10 % after low-calorie diet increased 25OHD levels , and this increase was mainly associated with improvement of insulin resistance CONTEXT Mono- and polyunsaturated fats may have opposing effects on vitamin D absorption . OBJECTIVE The purpose of this study was to determine whether intakes of different dietary fats are associated with the increase in serum 25-hydroxyvitamin D ( 25OHD ) after supplementation with vitamin D(3 ) . DESIGN , SETTING , AND PARTICIPANTS This analysis was conducted in the active treatment arm of a r and omized , double-blind , placebo-controlled trial of vitamin D and calcium supplementation to prevent bone loss and fracture . Subjects included 152 healthy men and women age 65 and older who were assigned to 700 IU/d vitamin D(3 ) and 500 mg/d calcium .  Intakes of monounsaturated fatty acids ( MUFA ) , polyunsaturated fatty acids ( PUFA ) , and saturated fatty acids ( SFA ) were estimated by food frequency question naire . MAIN OUTCOME MEASURE The change in plasma 25OHD during 2 yr  vitamin D and calcium supplementation was assessed . RESULTS The change in plasma 25OHD ( nanograms per milliliter ) during vitamin D supplementation was positively associated with MUFA , ( β = 0.94 ; P = 0.016 ) , negatively associated with PUFA , ( β = -0.93 ; P = 0.038 ) , and positively associated with the MUFA/PUFA ratio ( β = 6.46 ; P = 0.014 ) . CONCLUSION The fat composition of the diet may influence the 25OHD response to supplemental vitamin D(3 ) . Diets rich in MUFA may improve and those rich in PUFA may reduce the effectiveness of vitamin D(3 ) supplements in healthy older adults . More studies are needed to confirm these findings PURPOSE Vitamin D deficiency and cardiometabolic risk factors are common in obese adolescents . Observational studies demonstrate an inverse relationship among serum 25-hydroxyvitamin D ( 25OHD ) and obesity , insulin resistance , and inflammatory cytokines . This pilot study explores if vitamin D supplementation could reduce serum concentrations of inflammatory cytokines ( interleukin [ IL ] 6 , IL-10 , tumor necrosis factor α ) , adiponectin , lipids , hemoglobin A1C , and high-sensitivity C-reactive protein ( hs-CRP ) . A secondary aim was to determine the associations between baseline serum 25OHD concentrations and body mass index ( BMI ) , hs-CRP , inflammatory cytokines , and lipids . METHODS Overweight and obese adolescents enrolled in this 24-week , r and omized , double-blind study were given 150,000 IU ergocalciferol or placebo at baseline and 12 weeks . Outcome measurements included serum 25OHD , inflammatory cytokines , adiponectin , hs-CRP , lipids , hemoglobin A1C , and BMI at baseline , 12 , and 24 weeks . RESULTS Of 40 participants , 31 ( 78 % ) completed the study . Mean ± st and ard error 25OHD levels were similar in vitamin D and placebo groups at baseline ( 19.6 ± 5.3 vs. 25.8 ± 10.8 ng/mL ) and 24 weeks ( 20.1 ± 3.4 vs. 24.6 ± 8.4 ng/mL ) . Inflammatory and cardiovascular markers were not significantly different between groups at 24 weeks . Serum 25OHD at baseline was associated with BMI ( r = -.44 [ 95 % confidence interval , -.66 to -.15 ] ) but not with other outcome measures . CONCLUSIONS Supplementation with vitamin D at 150,000 IU every 3 months failed to increase serum 25OHD or alter inflammatory markers and lipids in overweight and obese youth . Further studies are needed to establish the dose of vitamin D required to increase 25OHD and determine potential effects on metabolic risk factors in obese teens Summary The effects of higher than recommended vitamin D doses on bone mineral density ( BMD ) and quality are not known . In this study , higher intakes , in postmenopausal women undergoing weight control over 1 year , had no effect on areal or volumetric BMD but prevented the deterioration in cortical bone geometry . Introduction Studies examining how bone responds to a st and ard dose of vitamin D supplementation have been inconsistent . In addition , the effects of higher doses on BMD and quality are not known . Postmenopausal women undergoing weight control to improve health outcomes are particularly at risk for bone loss and might benefit from supplemental vitamin D intake above the recommended allowance . Methods This 1-year-long , r and omized , double-blind controlled study addresses whether vitamin D supplementation , in healthy overweight/obese older women , affects BMD and bone structural parameters . In addition , bone turnover and serum total , free , and bioavailable 25-hydroxyvitamin D ( 25OHD ) responses to one of three daily levels of vitamin D3 ( 600 , 2000 , 4000 IU ) with 1.2 Ca g/day during weight control were examined . Results Fifty-eight women ( age , 58 ± 6 years ; body mass index , 30.2 ± 3.8 kg/m2 , serum 25OHD , 27.3 ± 4.4 ng/mL ) were r and omized to treatment . After 1 year , serum 25OHD concentrations increased to 26.5 ± 4.4 , 35.9 ± 4.5 , and 41.5 ± 6.9 ng/mL , in groups 600 , 2000 , and 4000 IU , respectively , and differed between groups ( p < 0.01 ) . Weight change was similar between groups ( −3.0 ± 4.1 % ) . Cortical ( Ct ) thickness of the tibia changed by −1.5 ± 5.1 % , + 0.6 ± 3.2 % , and + 2.0 ± 4.5 % in groups 600 , 2000 , and 4000 IU , respectively , and each group was significantly different from each other ( p < 0.05 ) . Conclusion The decline in Ct thickness was prevented with higher vitamin D3 supplementation , but there were no other significant changes due to treatment over 1 year . Whether these findings translate to changes in biomechanical properties leading to reduced fracture risk should be addressed in future studies The loss of weight was analysed in a group of sixty overweight/obese women of childbearing age ( 20 - 35 years ) according to their initial vitamin D status . Subjects were r and omly assigned to one of two slightly hypocaloric diets : Diet V , in which the consumption of vegetables was increased , or Diet C , in which the relative consumption of cereals ( especially breakfast cereals ) was increased .  Dietetic , anthropometric and biochemical data were collected at the start of the study and again at 2 weeks after dividing the women into groups depending on their having an initial serum 25-hydroxyvitamin D ( 25(OH)D ) concentration of < 50 nmol/l ( LD ) or > or=50 nmol/l ( HD ) . Dietary intervention led to a reduction in energy intake , body weight and BMI in all groups . The HD women showed greater body fat losses during the study than the LD women ( 1.7 ( SD 1.8 ) kg compared to 0.5 ( SD 0.8 ) kg ) . A better vitamin D status therefore aided the loss of body fat over the experimental period ( OR 0.462 ; CI 0.271 , 0.785 ; P < 0.001 ) . However , when the dietary groups were analysed separately , this effect was only seen in the C subjects ( OR 0.300 ; CI 0.121 , 0.748 ; P < 0.001 ) . The present results suggest that women with a better vitamin D status respond more positively to  hypocaloric diets  and lose more body fat ; this was especially clear among the C subjects who had a greater vitamin D supply during the experimental period 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 Background : Dairy products not only reduce the risk of hypertension and cardiovascular diseases but may play a role in the treatment of obesity . As there is some evidence that calcium ( Ca ) and vitamin D may play a role in effective weight management , we decided to evaluate the influence of Ca and vitamin D supplementation on weight and fat loss  in obese women . Material and Methods : Forty obese women were enrolled in this study . Subjects were divided into 2 groups comparable with body mass index ( BMI ) and age . Group 1 was provided with calcium carbonate and 1-(OH)-vitamin D supplementation . Group 2 was provided with only a diet . Subjects participated in a 3-month weight reduction therapy ( balanced diet , modification of life style , and regular physical exercise ) . Blood sample s ( serum concentration of Ca , phosphorus ( P ) , parathormone ( PTH ) , 25-(OH)-D3 ) and clinical characteristics ( weight , height , BMI , body composition ) were taken at baseline and after the 3-month program . Results : No significant differences of body weight , body fat content , serum parathormone , 25-(OH)-D3 concentration , and plasma total Ca and P concentration were observed between analyzed groups both before and after the treatment . Additionally , we did not observe any significant influence of Ca and vitamin D supplementation on weight and fat loss . Conclusion : Ca plus vitamin D supplementation during a 3-month low caloric diet has no additional effect on weight and fat loss in obese women Low levels of 25-hydroxyvitamin D ( 25OHD ) are associated with increased bone turnover and risk of fractures . Plasma 25OHD is inversely related to body mass index , and vitamin D deficiency is common in obesity . We aim ed to determine whether vitamin D supplementation affects bone turnover and bone mineral density ( BMD ) in obese subjects . Fifty-two healthy obese men and women aged 18–50 years with plasma 25OHD levels below 50 nmol/L were r and omized to 7,000 IU of cholecalciferol daily or placebo for 26 weeks . We measured plasma levels of 25OHD , parathyroid hormone ( PTH ) , and markers of bone turnover , as well as BMD at the hip , spine , forearm , and whole body . Compared with placebo , treatment with cholecalciferol  increased mean plasma 25OHD from 35 to 110 nmol/L ( p < 0.00001 ) and significantly decreased PTH ( p < 0.05 ) . BMD increased significantly at the forearm by 1.6 ± 0.7 % ( p = 0.03 ) . The bone resorption marker C-terminal telopetide of type 1 collagen ( CTX ) decreased borderline significantly in the cholecalciferol group compared with the placebo group ( p = 0.07 ) . Changes in plasma 25OHD correlated inversely with changes in plasma levels of bone-specific alkaline phosphatase ( r = −0.38 , p = 0.01 ) and CTX ( r = −0.33 , p = 0.03 ) . Changes in CTX correlated inversely with changes in spine BMD ( r = −0.45 , p = 0.04 ) . Increasing circulating 25OHD levels by cholecalciferol treatment is of importance to bone health in young obese subjects as increased levels of 25OHD are associated with a decrease in both PTH and bone turnover and with an increase in BMD at the forearm BACKGROUND Vitamin D deficiency is associated with obesity ; whether repletion supports weight loss and changes obesity-related biomarkers is unknown . OBJECTIVE We compared 12 mo of vitamin D3 supplementation with placebo  on weight , body composition , insulin , and C-reactive protein ( CRP ) in postmenopausal women in a weight-loss intervention . DESIGN A total of 218 overweight/obese women ( 50 - 75 y of age ) with serum 25-hydroxyvitamin D [ 25(OH)D ] ≥10 ng/mL but < 32 ng/mL were r and omly assigned to weight loss + 2000 IU oral vitamin D3/d or weight loss + daily placebo . The weight-loss intervention included a reduced-calorie diet ( 10 % weight loss goal ) and 225 min/wk of moderate-to-vigorous aerobic activity . Mean 12-mo changes in weight , body composition , serum insulin , CRP , and 25(OH)D were compared between groups ( intent-to-treat ) by using generalized estimating equations . RESULTS A total of 86 % of participants completed the 12-mo measurements . The mean ( 95 % CI ) change in 25(OH)D was 13.6 ( 11.6 , 15.4 ) ng/mL in the vitamin D3 arm compared with -1.3 ( -2.6 , -0.3 ) ng/mL in the placebo arm ( P < 0.0001 ) . Changes in weight [ -7.1 ( -8.7 , -5.7 ) compared with -7.4 ( -8.1 , -5.4 ) kg ] , body mass index ( in kg/m(2 ) : both -2.8 ) , waist circumference [ -4.9 ( -6.7 , -2.9 ) compared with -4.5 ( -5.6 , -2.6 ) cm ] , percentage body fat [ -4.1 ( -4.9 , -2.9 ) compared with -3.5 ( -4.5 , -2.5 ) ] , trunk fat [ -4.1 ( -4.7 , -3.0 ) compared with -3.7 ( -4.3 , -2.9 ) kg ] , insulin [ -2.5 ( -3.4 , -1.7 ) compared with -2.4 ( -3.3 , -1.4 ) μU/mL ] , and CRP [ -0.9 ( -1.2 , -0.6 ) compared with -0.79 ( -0.9 , -0.4 ) mg/L ] [ corrected ] were similar between groups ( all P > 0.05 ) . Compared with women who achieved 25(OH)D < 32 ng/mL , women r and omly assigned to vitamin D who became replete ( ie , 25(OH)D ≥32 ng/mL ) lost more weight [ -8.8 ( -11.1 , -6.9 ) compared with -5.6 ( -7.2 , -5.0 ) kg ; P = 0.05 ] , waist circumference [ -6.6 ( -9.3 , -4.3 ) compared with -2.5 ( -4.6 , -2.0 ) cm ; P = 0.02 ] , and percentage body fat [ -4.7 ( -6.1 , -3.5 ) compared with -2.6 ( -3.9 , -2.2 ) ; P = 0.04 ] . Among women with complete pill counts ( 97 % adherence ) , the mean decrease in CRP was 1.18 mg/mL ( 46 % ) in the vitamin D arm compared with 0.46 mg/mL ( 25 % ) in the placebo arm ( P = 0.03 ) . CONCLUSIONS Vitamin D3 supplementation  during weight loss did not increase weight loss or associated factors compared with placebo ; however , women who became replete experienced greater improvements . This trial was registered at clinical trials.gov as NCT01240213 Background . Research on dairy foods to enhance weight and fat loss when incorporated into a modest weight loss diet has had mixed results . Objective . A 15-week controlled feeding study to determine if dairy foods enhance central fat and weight loss when incorporated in a modest energy restricted diet of overweight and obese adults . Design . A 3-week run-in to establish energy needs ; a 12-week 500 kcal/d energy reduction with 71 low-dairy-consuming overweight and obese adults r and omly assigned to diets : ≤1 serving dairy/d ( low dairy , LD ) or ≤4 servings dairy/d ( adequate dairy , AD ) . All foods were weighed and provided by the metabolic kitchen . Weight , fat , intra-abdominal adipose tissue ( IAAT ) , subcutaneous adipose tissue ( SAT ) macrophage number , SAT inflammatory gene expression , and circulating cytokines were measured . Results . No diet differences were observed in weight , fat , or IAAT loss ; nor SAT mRNA expression of inflammation , circulating cytokines , fasting lipids , glucose , or insulin . There was a significant increase ( P = 0.02 ) in serum 25-hydroxyvitamin D in the AD group . Conclusion . Whether increased dairy intake during weight loss results in greater weight and fat loss for individuals with metabolic syndrome deserves investigation . Assessment of appetite , hunger , and satiety with followup on weight regain should be considered Vitamin  D deficiency and oral diseases ( periodontitis , caries , and tooth loss ) are highly prevalent in Germany . Previous studies suggested that vitamin D might be a modifiable and protective factor for periodontitis , caries , and tooth loss . However , prospect i ve studies investigating such associations are limited . We explored the association between the concentration of  serum 25-hydroxy vitamin D ( 25OHD ) and incidence of tooth loss , progression of clinical attachment loss ( CAL ) ≥ 3 mm , and progression of restorative and caries status in a population -based longitudinal study . We analyzed data from 1,904 participants from the Study of Health in Pomerania with a five-year follow-up . Generalized estimating equation models were applied to evaluate tooth-specific associations between serum 25OHD and incidence of tooth loss , progression of CAL ≥ 3 mm , and progression of restorative and caries status . Age , sex , education , smoking status , alcohol drinking , waist circumference , dental visit frequency , reasons of dental visit , vitamin D or calcium supplements , and season of blood draw were considered as confounders . Serum 25OHD was inversely associated with incidence of tooth loss . A significant dose-response relationship ( p = .0022 ) was observed across the quintiles of serum 25OHD . After adjusting for multiple confounders , each 10-µg/L increase of serum 25OHD was associated with a 13 % decreased risk of tooth loss ( risk ratio : 0.87 ; 95 % confidence interval : 0.79 , 0.96 ) . The association was attenuated for changes of CAL ≥ 3 mm when adjusting for multiple confounders . No significant association was found between serum 25OHD and caries progression  . Vitamin D might be a protective factor for tooth loss . The effect might partially be mediated by its effect on periodontitis OBJECTIVE Investigate whether cholecalciferol supplementation leads to weight loss in overweight and obese adults . DESIGN R and omized double blind clinical trial with 20,000 IU cholecalciferol twice a week , or 20,000 IU once a week plus placebo , or placebo twice a week , for 12 months . All subjects were given 500 mg calcium supplementation . METHODS Four hundred and forty five healthy , overweight , and obese men and women ( age 21 - 70 years , body mass index ( BMI ) 28.0 - 47.0 kg/m(2 ) ) .  Body weight , fatness , and fat distribution parameters were measured by dual-energy X-ray absorptiometry and anthropometry , blood sample s and 24-h urinary sample s were collected . RESULTS At baseline , there were no significant differences between the groups , but there was a significant inverse relation between serum 25-hydroxyvitamin D ( 25(OH)D ) levels and BMI , and a significant positive association between calorie intake and BMI .  Three hundred and thirty four subjects completed the study . During the study , there was no significant change in weight , waist-to-hip ratio ( WHR ) or percentage body fat in any of the groups , nor between them . Parathyroid hormone decreased and 25(OH)D increased significantly in both groups receiving cholecalciferol , and serum levels of 25(OH)D stabilized after 3 months . Serum calcium was unchanged in all groups . Urinary calcium excretion increased in all groups , but there was no significant difference between the groups . Weekly dosage of 20,000 - 40,000 IU cholecalciferol for 12 months was associated with a low risk of adverse effects , at least in overweight and obese adults living at latitude 70 degrees N. CONCLUSION Significant weight reduction in overweight and obese subjects is unlikely to occur with cholecalciferol supplementation Purpose The serum 25-hydroxyvitamin D ( 25(OH)D ) levels are lower in obese than lean subjects . The present study examines the cross-sectional and longitudinal relations between body mass index ( BMI ) and serum 25(OH)D , and the serum 25(OH)D response to vitamin D supplementation  in relation to BMI . Methods The Tromsø study is a longitudinal population -based multi purpose study . The fourth survey was conducted in 1994 and the sixth in 2008 . The intervention study was a 1-year placebo-controlled r and omized intervention trial , where the results from the 93 subjects given 40,000 IU per week are presented . Results A total of 10,229 subjects were included in the 2008 cross-sectional study . There was a significant negative association between serum 25(OH)D levels and BMI which was also present during the winter months . Serum 25(OH)D levels varied through seasons , but not BMI . In the longitudinal study from 1994 to 2008 which included 2,656 subjects , change in BMI was a significant negative predictor of change in 25(OH)D. In the intervention study , there was a significant and negative correlation between BMI and serum 25(OH)D both at baseline and at the end of the study . The increase in serum 25(OH)D after 1 year was significantly and inversely related to baseline BMI . Conclusions We have confirmed the strong association between serum 25(OH)D and BMI . The very obese need higher vitamin D doses than lean subjects to achieve the same serum 25(OH)D levels Vitamin D deficiency leads to secondary hyperparathyroidism , increased bone turnover , and bone loss and , when severe , to osteomalacia . Vitamin D deficiency is common in elderly people , especially the institutionalized . The definition of vitamin D deficiency is hampered by the fact that large interlaboratory differences exist in assays for serum 25-hydroxyvitamin D ( 25OHD ) , the main circulating metabolite . The international Multiple Outcomes of Raloxifene Evaluation study , a large prospect i ve intervention trial in postmenopausal women with osteoporosis , offered the opportunity to compare vitamin D status and parathyroid function throughout many countries over the world . For this study , baseline data were available from 7564 postmenopausal women from 25 countries on 5 continents . All women had osteoporosis , i.e. bone mineral density ( BMD ) at femoral neck or lumbar spine was lower than t-score -2.5 , or they had 2 vertebral fractures .  Serum 25OHD was measured by RIA , and  serum PTH  was measured by immunoradiometric assay .  BMD was measured by dual x-ray absorptiometry . The mean ( + /-SD ) serum 25OHD was 70.8 + /- 30.9 nmol/L. A low serum 25OHD ( < 25 nmol/L ) was observed in 4.1 % of all women in the Multiple Outcomes of Raloxifene Evaluation study , ranging from 0 % in south east Asia ( very few patients ) to 8.3 % in southern Europe . Serum 25OHD was between 25 - 50 nmol/L in 24.3 % of the women . Serum 25OHD showed a significant seasonal relationship , with lower values in all regions in winter . Serum PTH correlated negatively with serum 25OHD ( r = -0.25 ; P < 0.001 ) . This significant negative correlation was observed in all regions . When serum 25OHD was less than 25 , 25 - 50 , or more than 50 nmol/L , respectively , mean serum PTH levels were 4.8 , 4.1 , and 3.5 pmol/L , respectively ( by ANOVA , P < 0.001 ) . Similarly , mean alkaline phosphatase levels were 83.7 , 79.1 , and 75.7 U/L ( P < 0.001 ) , respectively , with increasing serum 25OHD . The effect of serum 25OHD on BMD was only significant for the BMD of the trochanter where a serum 25OHD level less than 25 nmol/L was associated with a 4 % lower BMD . After 6 months of treatment with vitamin D(3 ) ( 400 - 600 IU/day ) and calcium ( 500 mg/day ) , serum 25OHD increased from 70.8 + /- 29.8 to 92.3 + /- 28.6 nmol/L. Serum PTH decreased significantly after 6 months of treatment , and this decrease depended on baseline serum 25OHD . When baseline serum 25OHD was less than 25 , 25 - 50 , or more than 50 nmol/L , respectively , serum PTH decreased by 0.8 , 0.5 , or 0.2 pmol/L , respectively ( P < 0.001 ) . In conclusion , serum 25OHD was less than 25 nmol/L in 4 % of the women , and this was associated with a 30 % higher serum PTH . In 24 % of the women  serum 25OHD was between 25 - 50 nmol/L , associated with a 15 % higher level of serum PTH compared with women with a serum 25OHD greater than 50 nmol/L. A low serum 25OHD level was also associated with higher serum alkaline phosphatase and lower BMD of the trochanter . Treatment with vitamin D(3 ) and calcium increased serum 25OHD and decreased serum PTH significantly ; the effect was greater for lower baseline serum 25OHD OBJECTIVE : To assess the efficacy and tolerability of orlistat ( Xenical ® ) in producing and maintaining weight loss over a 12-month period . DESIGN : Patients were r and omized to double-blind treatment with either orlistat 120 mg or placebo three times daily , in conjunction with a low-energy diet , for 12 months . SETTING : Five centres in the UK.SUBJECTS : 228 obese adult patients with body mass index between 30 and 43 kg/m2 and mean weight 97 kg ( range 74–144 kg ) . INTERVENTIONS : All patients were prescribed a low-energy diet , providing 30 % of energy from fat , design ed to produce an individually tailored energy deficit of approximately 600 kcal/day , for a run-in period of 4 weeks and then 12 months , plus orlistat 120 mg or placebo three times daily . MAIN OUTCOME MEASURES : Change in body weight ( the primary efficacy parameter ) , waist circumference and adverse events were review ed regularly , together with serum lipids , insulin , glucose and plasma levels of fat-soluble vitamins and β carotene . RESULTS : Based on an intent-to-treat analysis , after 1 y of treatment patients receiving orlistat had lost an average of 8.5 % of their initial body weight compared with 5.4 % for placebo-treated patients ; 35 % of the orlistat group lost at least 5 % of body weight compared with 21 % of the placebo group ( P<0.05 ) , and 28 % and 17 % , respectively ( P=0.04 ) lost at least  10 %  of body weight . Orlistat-treated patients showed significant decreases ( P<0.05 ) in serum levels of total cholesterol , low density lipoprotein cholesterol , and in the low density lipoprotein : high density lipoprotein ratio in comparison with placebo . Both groups had similar adverse-event profiles , except for gastrointestinal events , which were 26 % more frequent in the orlistat group but were mostly mild and transient . To maintain normal plasma levels of fat-soluble vitamins , supplements of vitamins A , D and E were given to 1.8 % , 8.0 % and 3.6 % , respectively , of orlistat-treated patients , compared with 0.9 % of placebo-treated patients for each vitamin type . After 1 y , the decrease in vitamin E and β carotene was significantly greater in orlistat-treated patients compared with those receiving placebo ( P<0.001 ) . No significant change was found in the mean vitamin E : total cholesterol ratio in either group after 52 weeks . Conclusions : Orlistat , in conjunction with a low-energy diet , produced greater and more frequent significant weight loss  than placebo during 1 y of treatment . One-third of orlistat-treated patients achieved clinical ly relevant weight loss ( ≥5 % initial body weight ) . There was also an improvement in relevant serum lipid parameters . Fat-soluble vitamin supplements may be required during chronic therapy . Orlistat was well tolerated and offers a promising new approach to the long-term management of obesity BACKGROUND The role of dairy calcium intake and serum vitamin D concentrations in weight loss is controversial . OBJECTIVE The objective was to assess the association of dairy calcium intake and serum vitamin D with weight loss . DESIGN We analyzed data from participants in the 2-y Dietary Intervention R and omized Controlled Trial ( DIRECT ) [ n = 322 ; mean body mass index ( BMI ; in kg/m² ) : 31 ; mean age : 52 y ] . A representative sample ( n = 126 ) was followed for 6 mo for serum vitamin D changes . RESULTS Baseline serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations decreased significantly across the tertiles of baseline BMI ( 25.6 ± 8.0 , 24.1 ± 8.9 , and 22.9 ± 6.8 ng/mL , respectively ; P for trend = 0.02 ) . Baseline concentrations of vitamin D and dairy calcium  intake were not associated with subsequent weight loss . However , in repeated- measures models adjusted for age , sex , baseline BMI , total fat intake , and diet group assignment , higher 6-mo tertile levels of dairy calcium intake ( median for tertiles : 156.5 , 358.0 , and 582.9 mg/d , respectively ) and serum 25(OH)D ( 14.5 , 21.2 , and 30.2 ng/mL , respectively ) were associated with increased weight loss across the 2-y intervention ( -3.3 , -3.5 , and -5.3 kg , respectively , for dairy calcium ; P = 0.043 ; -3.1 , -3.8 , and -5.6 kg , respectively , for vitamin D ; P = 0.013 ) . In a multivariate logistic regression adjusted simultaneously for age , sex , baseline BMI , total fat intake , diet group , vitamin D concentration , and dairy calcium , an increase of 1 SD in  dairy calcium intake increased the likelihood of weight loss of > 4.5 kg in the preceding 6 mo [ odds ratio ( OR ) : 1.45 ; P = 0.046 ] . A similar increase was seen for serum 25(OH)D at the 6-mo point ( OR : 1.7 ; P = 0.009 ) . CONCLUSION Our study suggests that both higher dairy calcium intake and increased serum vitamin D are related to greater diet-induced weight loss . This trial was registered at clinical trials.gov as NCT00160108 Obesity has been linked with poorer vitamin D status . The aim of this work was to analyze the changes in vitamin D status and body weight of 61 young , overweight/obese women following two different weight control programs . The study subjects were r and omly assigned to one of two slightly hypocaloric diets : diet V , in which the consumption of greens and vegetables was increased , or diet C , in which the consumption of cereals ( some of which were enriched with vitamin D ) was increased .  Dietary , anthropometric , and biochemical data were collected at the start of the study and at 2 weeks . At the beginning of the study , when taking into account only those women with a vitamin D intake below that recommended , obese women had a significantly lower mean serum 25(OH)D concentration than those who were lighter . Dietary intervention led to a greater reduction in energy intake among group C subjects ; their weight was also that which was most reduced . In addition , the vitamin D intake and serum 25(OH)D values were increased only in group C women . Excess body weight was associated with deterioration in vitamin D status , especially when the intake of this vitamin was lower than that recommended . Subjects with higher serum vitamin D at the beginning of the study lost more weight than those subjects with lower initial values . Diet C was associated with a greater weight loss than diet V , and led to a greater increase in vitamin D intake and serum 25(OH)D levels . This might be of interest in the improvement of health in people trying to lose weight Objective The aim was to investigate whether vitamin D supplementation , combined with a hypocaloric diet , could have an independent effect on insulin sensitivity in subjects with both overweight and hypovitaminosis D. Changes from baseline in anthropometric parameters , body composition , glucose tolerance , and insulin secretion were considered as secondary outcomes . Methods Eighteen volunteers who were nondiabetic and vitamin D deficient and had BMI > 25 kg/m2 were r and omized ( 1:1 ) in a double‐blind manner to a hypocaloric diet + either oral cholecalciferol at 25,000 IU/wk or placebo for 3 months . Hyperinsulinemic‐euglycemic clamp to measure insulin sensitivity  was performed at baseline and after intervention . Results Body weight in both groups decreased significantly ( −7.5 % in the vitamin D group and −10 % in the placebo group ; P < 0.05 for both ) , with no between‐group differences . Serum 25‐hydroxyvitamin D levels in the vitamin D group increased considerably ( from 36.7 ± 13.2 nmol/L to 74.8 ± 18.7 nmol/L ; P < 0.001 ) . Insulin sensitivity in the vitamin D group improved ( from 4.6 ± 2.0 to 6.9 ± 3.3 mg·kg−1·min−1 ; P < 0.001 ) , whereas no changes were observed in the placebo group ( from 4.9 ± 1.1 to 5.1 ± 0.3 mg·kg−1·min−1 ; P = 0.84 ) . Conclusions Cholecalciferol supplementation , combined with a weight loss program , significantly improves insulin sensitivity in healthy subjects with obesity and might represent a personalized approach for insulin‐resistant subjects with obesity OBJECTIVES To compare the effects of 12 months of vitamin D3 supplementation with that placebo on lean mass , bone mineral density ( BMD ) , and muscle strength in overweight or obese postmenopausal women completing a structured weight-loss program . DESIGN Double-blind , placebo-controlled r and omized clinical trial . SETTING Fred Hutchinson Cancer Research Center , Seattle , Washington . PARTICIPANTS Postmenopausal women aged 50 to 75 with a body mass index ( BMI ) of 25 kg/m(2 ) or greater and a serum 25-hydroxyvitamin D ( 25(OH)D ) concentration between 10.0 and 32.0 ng/mL ( insufficient ) ( N = 218 ) . INTERVENTION Oral vitamin D3 2,000 IU/d or placebo in combination with a lifestyle-based weight loss intervention consisting of a reduction of 500 kcal to 1,000 kcal per day and 225 min/wk of moderate- to vigorous-intensity aerobic exercise .  MEASUREMENTS Serum 25(OH)D , body composition , and muscle strength were measured before r and omization ( baseline ) and at 12 months . Mean changes of the groups were compared ( intention to treat ) using generalized estimating equations . RESULTS Change in 25(OH)D was significantly different between the vitamin D and placebo groups at 12 months ( 13.6 ng/mL vs -1.3 ng/mL , P < .001 ) , but no differences in change in lean mass ( -0.8 kg vs -1.1 kg , P = .53 ) or BMD of the spine ( -0.01 g/cm(2 ) vs 0.0 g/cm(2 ) , P = .82 ) or right femoral neck ( both -0.01 g/cm(2 ) , P = .49 ) were detected between the groups . Leg strength decreased in the vitamin D group but not in the placebo group ( -2.6 pounds vs 1.8 pounds , P = .03 ) . In women r and omized to vitamin D , achieving repletion ( 25(OH)D ≥ 32 ng/mL ) did not alter results . CONCLUSION Vitamin D3 supplementation during weight-loss decreased leg strength but did not alter changes in lean mass or BMD in postmenopausal women with vitamin D insufficiency The objective of this study was to characterize changes in metabolic bone parameters following bariatric surgery .  Seventy-three obese adult patients who underwent either gastric b and ing ( GB ) , Roux-en-Y gastric bypass ( RYGB ) , or biliopancreatic diversion with duodenal switch ( BPD/DS )  were followed prospect ively for 18 months postoperatively . Changes in the calcium-vitamin D axis ( 25-hydroxyvitamin D ( 25OHD ) , 1,25-dihydroxyvitamin D ( 1,25(OH)(2)D ) , calcium , parathyroid hormone ( PTH ) ) , markers of bone formation ( osteocalcin , bone-specific alkaline phosphatase ) and resorption ( urinary N-telopeptide ( NTx ) ) , as well as bone mineral density ( BMD ) were assessed at 3-month intervals during this time period . Bariatric surgery result ed in significant and progressive weight loss over 18 months . With supplementation , 25OHD levels increased 65.3 % ( P < 0.0001 ) by 3 months , but leveled off and decreased < 30 ng/ml by 18 months . PTH initially decreased 21.4 % ( P = 0.01 ) at 3 months , but later approached presurgery levels . 1,25(OH)(2)D increased significantly starting at month 12 ( 50.3 % increase from baseline , P = 0.008 ) , and was positively associated with PTH ( r = 0.82 , P = 0.0001 ) . When stratified by surgery type , median PTH and 1,25(OH)(2)D levels were higher following combined restrictive and malabsorptive operations ( RYGB and BPD/DS ) compared to GB . Bone formation/resorption markers were increased by 3 months ( P < 0.05 ) and remained elevated through 18 months . Radial BMD decreased 3.5 % by month 18 , but this change was not significant ( P = 0.23 ) . Our findings show that after transient improvement , preoperative vitamin D insufficiency and secondary hyperparathyroidism persisted following surgery despite supplementation . Postoperative secondary hyperparathyroidism was associated with increased 1,25(OH)(2)D levels and increased bone turnover markers OBJECTIVE : In epidemiological studies , weight loss is usually associated with increased mortality rate . Contrarily , among obese people , weight loss reduces other risk factors for disease and death . We hypothesised that this paradox could exist because weight is used as an implicit adiposity index . No study has considered the independent effects of weight loss and fat loss on mortality rate . We studied mortality rate as a function of weight loss and fat loss . DESIGN : Analysis of ‘ time to death ’ in two prospect i ve population -based cohort studies , the Tecumseh Community Health Study ( 1890 subjects ; 321 deaths within 16 y of follow-up ) and the Framingham Heart Study ( 2731 subjects ; 507 deaths within 8 y of follow-up ) , in which weight and fat ( via skinfolds ) loss were assessable . RESULTS : In both studies , regardless of the statistical approach , weight loss was associated with an increased , and fat loss with a decreased , mortality rate ( P<0.05 ) . Each st and ard deviation ( s.d . ) of weight loss ( 4.6 kg in Tecumseh , 6.7 kg in Framingham ) was estimated to increase the hazard rate by 29 % ( 95 % confidence interval CI ) , ( 14 % , 47 % , respectively ) and 39 % ( 95 % CI , 25 % , 54 % respectively ) , in the two sample s. Contrarily , each s.d . of fat loss ( 10.0 mm in Tecumseh , 4.8 mm in Framingham ) was estimated to reduce the hazard rate 15 % ( 95 % CI , 4 % , 25 % ) and 17 % ( 95 % CI , 8 % , 25 % ) in Tecumseh and Framingham , respectively . Generalisability of these results to severely ( that is , body mass index BMI ) ≥34 ) obese individuals is unclear . CONCLUSIONS : Among individuals that are not severely obese , weight loss is associated with increased mortality rate and fat loss with decreased mortality rate Low vitamin D status in women of childbearing age may have implication s for health . Vitamin D status of New Zeal and ers ( NZ ) , based on low serum 25-hydroxyvitamin D ( 25OHD ) is suboptimal . Vitamin D status may be improved with supplements and /or fortified foods . Recently an Adequate Intake ( AI ) for Australia and NZ was set at 5 microg/d vitamin D. We aim ed to determine the effect of daily consumption of milk powder fortified with 5 microg vitamin D3 on serum 25OHD concentration over 12 wks . 73 non-pregnant women ( 18 - 47 y ) living in Dunedin , NZ ( 46 degrees S ) were r and omised to receive either unfortified ( control ) or fortified ( 5 microg vitamin D3 ) milk for 12 wks from January to April . Mean 25OHD was similar between groups at week 0 ( control 74 vs 76 nmol/L ) and fell significantly in both groups over the 12 weeks ( control 53 nmol/L , fortified 65 nmol/L ; p < 0.001 ) . After 12 wks the fortified milk group had a serum 25OHD 19 % ( 95 % CI ; 7 , 32 % ) higher ( 10 nmol/L ) than the control group after adjusting for baseline levels ( p < 0.001 ) . Daily consumption of fortified milk providing the current AI of 5 microg day vitamin D3 for 12 weeks result ed in higher 25OHD concentrations than control milk . This dose was not sufficient to prevent the seasonal decline in 25OHD . This study suggests an AI of 5 microg may be inadequate for New Zeal and ers to allow for seasonal changes in sunlight exposure , and is unlikely sufficient for other population s with low sunlight exposure Serum calcium concentration has recently been shown to predict cardiovascular mortality in a large health-screening program . Since impaired glucose tolerance ( IGT ) is an independent cardiovascular risk factor , we examined the association between glucose intolerance and serum calcium in a population -based cohort study . To characterize this association , we measured  total serum calcium , parathyroid hormone ( PTH ) , 25-hydroxyvitamin D ( 25OHD ) , and 1,25-dihydroxyvitamin D ( 1,25-(OH)2D ) levels  in a cohort of 1,071 r and omly selected white individuals aged 40 to 65 years in whom an oral glucose tolerance test had been completed . In multivariate analyses , the  2-hour plasma glucose  was positively associated with increasing total serum calcium and PTH in men and women after adjustment for age , obesity , season , and 25OHD . The adjusted odds ratio ( OR ) between increasing quintiles of total serum calcium and IGT was 1.63 ( 95 % confidence interval [ CI ] , 1.42 to 1.88 ) . The OR comparing the top with the bottom quintile was 8.5 ( 95 % CI , 4.5 to 16.0 ) . The association with quintile of serum PTH was 1.30 ( 95 % CI , 1.14 to 1.49 ) . These data suggest that IGT is associated with an increase in both total serum calcium and PTH that can not be explained by confounding by aging , obesity , or 25OHD . This relationship may explain the previously observed association between serum calcium and cardiovascular mortality . Whether this association is a manifestation of a shared cellular defect or represents a common relationship with an unknown etiologic factor are important questions for further research
Collectively , these outcomes support a volumetric dilution of vitamin D. The slopes of the respective regression lines , however , indicate a smaller increase in 25OHD than would be expected from a direct mobilization of stores into the circulation .
Hence , sequestration of 25OHD and its conversion to inactive metabolites would also play a role .
The purpose of this review was to confirm a volumetric dilution of vitamin D in obesity .
It was based on the hypothesis that weight loss , particularly fat loss , would increase serum 25-hydroxyvitamin D ( 25OHD ) in the obese .