25-hydroxyvitamin-d-2 and Obesity

Although both vitamin D deficiency and obesity are highly prevalent in the UAE, the role of vitamin D metabolites in mediating obesity-related adverse health effects is not clear. We aimed to assess the role of vitamin D metabolites as potential mediators in the association between obesity, inflammation and metabolic risk factors.. 277 participants who were part of a randomized controlled trial had their assessment that included clinical, anthropometric and physical activity data at baseline and at 6 months. Blood and urine samples were taken for measurements of serum 25(OH)D, 25(OH)D metabolites including 25(OH)D3), 25(OH)D2), 1,25(OH)2D3, 3-Epi-D3), metabolic and inflammatory markers and related biochemical variables. Multiple regression analysis used to assess the role of 25(OH)D metabolites in mediating the effect of increasing body mass index (BMI) on inflammation and metabolic risk factors.. Overall, 277 participants with complete 6 months follow up with a mean (±SD) age of 41 ± 12 and 204 (74%) female were included in the study. Blood pressure, inflammatory, metabolic and lipid profile markers significantly increased in overweight and obese subjects compared to subjects with normal BMI both at baseline and at 6 months (p < 0.05). 25(OH)D revealed significant association with age, gender, HbA1c and type 2 diabetes (p < 0.05). No statistically significant changes in any of 25(OH)D metabolites assessed. Multivariate analysis revealed significant and independent associations between BMI and important inflammatory and metabolic risk factors (p < 0.05). No similar association observed with 25(OH)D metabolites.. Although we found significant association between 25(OH)D and prevalence of type 2 diabetes, we found no evidence however to support a role of 25(OH)D metabolites in mediating the effect of BMI on inflammatory or metabolic risk factors.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Calcifediol; Calcitriol; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Multivariate Analysis; Obesity; Risk Factors; Vitamin D; Vitamin D Deficiency

Serum 25 hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) levels correlate inversely. The 25(OH)D level at which PTH is maximally suppressed and below which PTH begins to rise (inflection point) has been used to define optimum 25(OH)D levels. While serum 25(OH)D levels are lower in obese individuals, likely due to sequestration of vitamin D in the adipose tissue, it is not known if the lower 25(OH)D levels in obese children are associated with a PTH increase in the same manner as it is in normal weight children.. A retrospective record review of children between 2 and 18 years of age (n = 269) undergoing simultaneous measurement of serum 25(OH)D and PTH levels was performed.. The level of serum 25(OH)D below which PTH begins to rise was significantly lower (p < 0.001) in overweight/obese children compared to normal weight children [12.4 (95% CI 9.8-15.0) vs. 17.0 ng/ml (95% CI 11.4-22.6)].. In overweight and obese children, the PTH axis is activated at much lower 25(OH)D levels than in normal weight children. These findings are a consequence of similar ionized calcium levels in these groups despite lower serum 25(OH)D levels in obese children.

Topics: 25-Hydroxyvitamin D 2; Adolescent; Child; Female; Humans; Male; Medical Records; Obesity; Parathyroid Hormone; Retrospective Studies

Low circulating concentrations of vitamin D metabolites have been associated with increased risk for several diseases and clinical conditions. Large observational studies and surveys have shown that obesity is independently associated with lower serum 25-hydroxyvitamin D (25(OH)D) concentration. Few studies have examined the effect of weight loss on serum 25(OH)D concentration. The purpose of this study was to prospectively examine the effect of weight loss on serum 25(OH)D concentration. Data were collected from 383 overweight or obese women who participated in a 2-year clinical trial of a weight-loss program, in which 51% (N = 195) lost at least 5% of baseline weight by 24 months, 18% (N = 67) lost 5-10%, and 33% (N = 128) lost >10%. Women who did not lose weight at 24 months had an increase in serum 25(OH)D of 1.9 (9.7) ng/ml (mean (SD)); 25(OH)D increased by 2.7 (9.1) ng/ml for those who lost 5-10% of baseline weight; and 25(OH)D increased by 5.0 (9.2) ng/ml for those who lost >10% of baseline weight (P = 0.014). At baseline, 51% (N = 197) of participants met or exceeded the recommended serum concentration of 20 ng/ml. By study end, 64% (N = 230) of overweight or obese women met this goal, as well as 83% (N = 20) of those whose weight loss achieved a normal BMI. These findings suggest that weight loss, presumably associated with a reduction in body fat, is associated with increased serum 25(OH)D concentration in overweight or obese women.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Body Mass Index; Diet, Reducing; Exercise; Female; Humans; Middle Aged; Nutritional Status; Obesity; Prospective Studies; Vegetables; Weight Loss; Weight Reduction Programs

Vitamin D deficiency is associated with a variety of chronic metabolic diseases. Limited evidence regarding vitamin D deficiency exists within the Chinese population. The present study aims to examine the association between serum vitamin D concentrations and cardiometabolic risk factors in the young and middle-aged, urban Chinese population. The cross-sectional relationships between serum 25-hydroxyvitamin D [25(OH)D] concentrations and indices of adiposity and cardiometabolic risk factors (e.g., body mass index, waist circumference, fasting plasma glucose, etc.) were evaluated in 601 non-diabetic adults.. Vitamin D deficiency or insufficiency was present in 66% of the tested population, and serum 25(OH)D levels were lower in patients who were overweight/obese or suffered metabolic syndrome when compared to individuals of healthy weight without metabolic syndrome (24.08 ± 8.08 vs 31.70 ± 11.77 ng/ml, 21.52 ± 6.9 vs 31.74 ± 10.21 ng/ml respectively). 25(OH)D was inversely associated with waist circumference, fasting glucose, fasting insulin, triglycerides and LDL-cholesterol, and it was positively associated with HDL-cholesterol in a multivariable-adjusted regression model.. Vitamin D deficiency is common in the young and middle-aged, urban Chinese population, with high prevalence in overweight/obese individuals and patients with metabolic syndrome. Low vitamin D concentration was associated with indices of adiposity and cardiometabolic risk factors. Further studies are warranted to elucidate the cause-effect relation between vitamin D status, obesity and related metabolic disorders.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Body Mass Index; Calcifediol; China; Cohort Studies; Cross-Sectional Studies; Female; Hospitals, Urban; Humans; Incidence; Male; Metabolic Syndrome; Middle Aged; Obesity; Overweight; Prevalence; Risk Factors; Severity of Illness Index; Urban Health; Vitamin D Deficiency

Vitamin D concentrations are linked to body composition indices, particularly body fat mass. Relationships between hypovitaminosis D and obesity, described by both BMI and waist circumference, have been mentioned. We have investigated the effect of a 12-week vitamin D3 supplementation on anthropometric indices in healthy overweight and obese women.. In a double-blind, randomized, placebo-controlled, parallel-group trial, seventy-seven participants (age 38 ± 8.1 years, BMI 29.8 ± 4.1 kg/m²) were randomly allocated into two groups: vitamin D (25 μg per day as cholecalciferol) and placebo (25 μg per day as lactose) for 12 weeks. Body weight, height, waist, hip, fat mass, 25(OH) D, iPTH, and dietary intakes were measured before and after the intervention.. Serum 25(OH)D significantly increased in the vitamin D group compared to the placebo group (38.2 ± 32.7 nmol/L vs. 4.6 ± 14.8 nmol/L; P<0.001) and serum iPTH concentrations were decreased by vitamin D3 supplementation (-0.26 ± 0.57 pmol/L vs. 0.27 ± 0.56 pmol/L; P<0.001). Supplementation with vitamin D3 caused a statistically significant decrease in body fat mass in the vitamin D group compared to the placebo group (-2.7 ± 2.1 kg vs. -0.47 ± 2.1 kg; P<0.001). However, body weight and waist circumference did not change significantly in both groups. A significant reverse correlation between changes in serum 25(OH) D concentrations and body fat mass was observed (r = -0.319, P = 0.005).. Among healthy overweight and obese women, increasing 25(OH) D concentrations by vitamin D3 supplementation led to body fat mass reduction.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Body Mass Index; Calcifediol; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Humans; Iran; Middle Aged; Obesity; Overweight; Parathyroid Hormone; Patient Compliance; Patient Dropouts; Time Factors; Vitamin D Deficiency

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 randomly 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.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Diet Records; Diet, Reducing; Edible Grain; Female; Food, Fortified; Humans; Nutrition Policy; Nutritional Status; Obesity; Overweight; Vegetables; Vitamin D; Weight Loss; Young Adult

A significant relationship between body weight (BW) and bone mass (BM) has been established previously. A diet-induced weight loss is accompanied by a significant decrease in bone mineral density (BMD) and total body bone mineral (TBBM), but the underlying mechanisms are not clarified. Sixty-two obese women were included in the study. Dual-energy X-ray absorptiometry (DXA) and measurements of a series of calcium-regulating hormones and biochemical markers of bone turnover were performed at baseline and after 1 month and 3 months on a low calorie diet. Thirty of the women were randomized to a daily supplement of 1 g of calcium. After an additional 3 months without dietary prescriptions or calcium supplements, a subgroup of 48 subjects (24 from each group) were scanned again using DXA. There was a significant decrease in TBBM after 1 month and 3 months. A similar pattern was observed in the bone mineral content (BMC) of the lumbar spine in the patients who did not receive a calcium supplement, whereas no changes occurred in the supplemented group. The initial calcium supplementation seemed to protect against bone loss in the lumbar spine but not in the TBBM. In the nonsupplemented group, a statistically significant inverse correlation was found between the calcium/creatinine ratio in the morning urine and the changes in BMC of the lumbar spine. Such a relationship was not seen in the calcium-supplemented group. In the nonsupplemented group, no significant biochemical changes were observed, whereas a significant decrease in serum parathyroid hormone (PTH) was seen in the calcium-supplemented group. This might explain some of the protective effects of calcium supplementation on trabecular bone mass. We conclude that a diet-induced weight loss is accompanied by a generalized bone loss, which probably is explained mainly by a reduced mechanical strain on the skeleton. This loss can be partly inhibited by a high calcium intake. Therefore, a calcium supplementation should be recommended during weight loss, even if the diet contains the officially recommended amounts of calcium.

Topics: 25-Hydroxyvitamin D 2; Amino Acids; Body Mass Index; Bone Density; Calcitriol; Calcium; Creatinine; Diet; Dietary Supplements; Female; Hip Joint; Humans; Lumbar Vertebrae; Obesity; Osteocalcin; Random Allocation; Weight Loss

To investigate the association of VitD with GDM, and examine the potential modifying effect of prepregnancy BMI in Chinese pregnant women.. 3318 pregnant women underwent oral glucose tolerance test (OGTT) were selected from Zhoushan Pregnant Women Cohort. Plasma VitD levels were measured in the first (T1) and/or second trimester (T2). Multiple linear and logistic regression models were used for evaluating the association of VitD with GDM.. Prepregnancy BMI was positively associated with all three time-point glucose of OGTT. 25(OH)D level in T1 (β = -0.003) and T2 (β = -0.004), and its change from T1 to T2 (β = -0.004) were significantly and inversely associated with fasting blood glucose (FBG) of OGTT, but not 1-h and 2-h postload blood glucose of OGTT, respectively. The negative associations of VitD and FBG were stronger among overweight/obese women. VitD deficiency (25(OH)D < 20 ng/ml) in T2 was associated with an increased risk of GDM with increased FBG, GDM subtype 1 (OR: 2.10) and subtype 3 (OR: 2.19). Moreover, prepregnancy BMI modified this effect on GDM subtype 1 (BMI < 24: OR = 1.42; BMI ≥ 24: OR = 9.61, P for interaction = 0.002). Lower VitD increment from T1 to T2 was associated with a higher risk for GDM among overweight/obese women. Additionally, GDM prevalence fluctuated with the season, i.e. lower in summer/fall and higher in winter/spring.. Maternal VitD deficiency was associated with a higher risk of GDM subtype with increased FBG, and the risk is much greater among overweight/obesity women. The lower the VitD increment during pregnancy, the greater the risk of GDM, especially in overweight/obesity women. Furthermore, seasonal variation of GDM may be exhibited as a critical confounder in the association of VitD and GDM.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Blood Glucose; Body Mass Index; Calcifediol; Diabetes, Gestational; Fasting; Female; Glucose Tolerance Test; Humans; Obesity; Pregnancy; Pregnancy Trimesters; Prospective Studies; Risk Assessment; Risk Factors; Seasons; Vitamin D Deficiency

Current studies support the implication of metabolic changes associated with type 2 diabetes in altering bone metabolism, structure and resistance.. We conducted a cross-sectional study on postmenopausal women aimed to analyze the differences in metabolic and bone profile in patients with and without type 2 diabetes Methods. We analyzed the metabolic and bone profile in postmenopausal women with and without type 2 diabetes (T2DM). Clinical, metabolic, hormonal parameters, along with lumbar, hip and femoral bone mineral density (BMD) and trabecular bone score (TBS) were evaluated.. 56 women with T2DM(63.57±8.97 years) and 83 non-T2DM (60.21±8.77 years) were included. T2DM patients presented a higher value of body mass index (BMI) and BMD vs. control group (p = 0.001; p = 0.03-lumbar level, p = 0.07-femoral neck and p = 0.001-total hip). Also, BMI correlated positively with lumbar-BMD and glycated hemoglobin (HbA1c) (r = 0.348, p = 0.01; r = 0.269, p = 0.04), correlation maintained even after age and estimated glomerular filtration rate (eGFR) adjustment (r = 0.383, p = 0.005; r = 0.237, p = 0.08). Diabetic patients recorded lower levels of 25(OH)D(p = 0.05), bone markers (p ≤ 0.05) and TBS(p = 0.07). For the entire patient group we found a negative correlation between HbA1c level and bone markers: r = -0.358, p = 0.0005-osteocalcin, r = -0.40, p = 0.0005-P1NP, r = -0.258, p = 0.005-crosslaps.. Our results indicate the presence of altered bone microarchitecture in T2DZ patients according to the TBS score, combined with lower levels of bone markers, with a statistically significant negative correlation between HbA1c level and bone markers.

Topics: 25-Hydroxyvitamin D 2; Aged; Biomarkers; Body Mass Index; Bone and Bones; Bone Density; Bone Resorption; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Middle Aged; Obesity; Osteocalcin; Peptide Fragments; Postmenopause; Procollagen

Resting metabolic rate (RMR) used to prognosticate and measure the amount of energy required. Vitamin D is known as a new predictor of RMR. The aim of this study is to investigate the relationship between vitamin D effects on RMR in connection with the vitamin D receptor (VDR) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) gene expression.. We enrolled 298 overweight and obese adults in this cross-sectional study. Body mass index (BMI), fat mass, fat-free mass, insulin level, visceral fat, and vitamin D status were assessed. RMR was measured by means of indirect calorimetry. The real-time polymerase chain reaction using specific primer pairs for VDR and PGC-1α was performed.. There were significant differences in terms of fat free mass, fat percentage, insulin levels, RMR/kg body weight, and RMR/BMI, VDR, and PGC-1α among participants were categorized based on the vitamin D status. But after using general linear model for adjusting, all significant results missed their effectiveness except RMR/kg body weight and VDR. Linear regression analysis used to show the mediatory role of VDR and PGC-1α on the RMR/kg body weight and vitamin D status relationship. Our results showed that VDR had a mediatory effect on the relationship between RMR/kg body weight and vitamin D status (β = 0.38, 95% CI -0.48 to 1.60; β = -1.24, 95% CI -5.36 to 1.70). However, PGC-1α did not affect the relationship between RMR/kg body weight and vitamin D status (β = 0.50, 95% CI = -0.02 to 3.42; β = 0.59, 95% CI 0.14-3.90).. Our study showed the mediatory effect of VDR gene expression in the association of 25(OH)2D plasma levels and resting metabolic rate among obese individuals.

Topics: 25-Hydroxyvitamin D 2; Adult; Basal Metabolism; Body Mass Index; Body Weight; Cross-Sectional Studies; Female; Humans; Logistic Models; Male; Nutritional Status; Obesity; Overweight; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Receptors, Calcitriol

Maternal vitamin D deficiency has been implicated in adverse pregnancy outcomes. However, the association between vitamin D and inflammation, particularly adipokines, remains unexplored in pregnancy.. In 102 overweight or obese pregnant women at high-risk of gestational diabetes mellitus (GDM), we investigated relationships between maternal 25-hydroxyvitamin D (25(OH)D) concentrations at 12-15 wk gestation (baseline) and serum lipids, inflammatory markers, novel adipokines (omentin-1, visfatin, high molecular weight (HMW) adiponectin), and subsequent pregnancy outcomes (GDM, preeclampsia, preterm birth [PTB]). After adjustment for maternal factors (age, BMI, parity, ethnicity, and smoking status), baseline 25(OH)D concentrations were inversely associated with total cholesterol and triglycerides, and positively associated with HMW-adiponectin. Higher baseline 25(OH)D concentrations were associated with decreased fasting and 1-h post-OGTT glucose and reduced risk of GDM at 26-28 wk, as well as with longer gestation and reduced risk of PTB upon additional adjustment for caesarean section. Adding HMW-adiponectin to the multivariable models attenuated most associations, and HMW-adiponectin was a significant predictor in the models.. Our findings suggest that lower maternal 25(OH)D concentrations in overweight/obese pregnant women at high-risk of GDM are associated with increased cardiometabolic risks during pregnancy and adverse pregnancy outcomes, and that these associations may be mediated by HMW-adiponectin.

Topics: 25-Hydroxyvitamin D 2; Adiponectin; Adult; Biomarkers; Body Mass Index; Calcifediol; Cardiovascular Diseases; Cohort Studies; Cross-Sectional Studies; Diabetes, Gestational; Female; Hospitals, Teaching; Humans; Maternal Nutritional Physiological Phenomena; Molecular Weight; Obesity; Overweight; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Pregnancy Trimester, Second; Risk; Victoria; Vitamin D Deficiency

Ongoing studies in the Middle East, particularly in the Arabian Gulf countries, have reported extremely low levels of serum vitamin D across age and gender. In Kuwait, vitamin D deficiency is prevalent in adolescent girls and in adult women. A number of risk factors have been reported, among which gender, age, and obesity are a few. Because adequate vitamin D status is necessary to promote bone mineral accrual in childhood, and because low vitamin D levels have been associated with a wide range of health problems, there is concern that growing children with low vitamin D may be at higher risk for developing diseases. The aim of this study was to assess vitamin D levels in elementary schoolchildren.. Kuwaiti schoolchildren were recruited and assessed for their serum vitamin D, 25(OH)D, parathyroid hormone (PTH) and adjusted serum calcium (adj-Ca). Anthropometric measurements and data on lifestyle and health status were recorded during an interview.. In a total of 199 schoolchildren, median (IQR) age was 8.5 (7.0-9.5 years), 25(OH)D was 30 (22-39 nmol/L), PTH was 4.7 (3.8-5.9 pmol/L), and adj-Ca was 2.39 (2.33-2.44 mmol/L). Boys had higher levels of 25(OH)D (18.3% vs 6.6% had levels ≥50 nmol/L) and lower levels of PTH (94.6% vs 80.2% had levels <7 pmol/L) than girls. Significant risk factors for 25(OH)D levels <25 nmol/L included being ≤8.5 years old (OR 4.95, 95% CI: 1.92-12.74), having PTH ≥7 pmol/L (OR 2.28, 95% CI: 1.17-4.46), being female (OR 2.44, 95% CI: 1.22-4.88), and being overweight or obese (OR 2.18, 95% CI: 1.11-4.26).. The results show relatively low levels of 25(OH)D in young schoolchildren in Kuwait, with lower levels in girls. Given the association of 25(OH)D with a wide range of ailments, it is necessary to further examine the causes and risk factors of low vitamin D in this age group to prevent associated health problems.

Topics: 25-Hydroxyvitamin D 2; Age Factors; Calcium; Child; Cross-Sectional Studies; Female; Humans; Kuwait; Male; Obesity; Parathyroid Hormone; Risk Factors; Sex Factors; Vitamin D; Vitamin D Deficiency

The association of vitamin D status with high body adiposity is poorly investigated in the chronic kidney disease (CKD) population. The aim of the present study was to describe vitamin D status and to identify body adiposity predictors of vitamin D deficiency, in a nondialyzed CKD population inhabiting a tropical city.. This cross-sectional study included patients with CKD, defined as estimated glomerular filtration rate (eGFR) <60 mL/min, regularly treated by an interdisciplinary team in an outpatient university clinic, set in a Brazilian city (latitude: 22°54'S; 43°12'W). Adiposity parameters analyzed were body mass index (BMI), total body adiposity (dual-energy x-ray absorptiometry [DXA] and body adiposity index [BAI]), and central body adiposity (DXA-trunk fat and waist-to-height ratio [WHtR]). Laboratory parameters included serum concentrations of 25-hydroxyvitamin D, phosphate, parathyroid hormone, and insulin (insulin resistance [IR evaluation: homeostasis model assessment; HOMA]).. Just under half of the CKD population presented sufficient concentration of 25-hydroxyvitamin D. Total body adiposity, independent of age and eGFR, regardless if evaluated by DXA or BAI, was the predictor of vitamin D deficiency, which in turn was associated with higher serum phosphorus and hyperparathyroidism, but not with IR.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Aged; Body Mass Index; Brazil; Calcifediol; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Models, Biological; Nutritional Status; Obesity; Overweight; Prevalence; Renal Insufficiency, Chronic; Risk Factors; Severity of Illness Index; Tropical Climate; Vitamin D Deficiency; Waist-Height Ratio

Low plasma 25-hydroxy-vitamin D (25OHD) and high levels of parathyroid hormone (PTH) are associated with obesity and could play a role in the occurrence of complications such as insulin resistance. The objective of the study was to evaluate whether the relationship between 25OHD status and phosphocalcic parameters differs between metabolically healthy obese (MHO) and insulin-resistant obese (IRO). This cross-sectional study included 158 consecutive adults (121 females) with obesity (body mass index (BMI) 35.15 ± 2.8 kg/m

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Biomarkers; Body Mass Index; Calcifediol; Cohort Studies; Comorbidity; Cross-Sectional Studies; Female; France; Humans; Insulin Resistance; Male; Middle Aged; Nutritional Status; Obesity; Obesity, Metabolically Benign; Parathyroid Hormone; Prediabetic State; Prevalence; Vitamin D Deficiency

The relationship between 25 hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and metabolic traits appear to differ among ethnicities and may be influenced by obesity. The aim of the study was to examine the association of serum 25(OH)D or PTH with metabolic syndrome (MetS) while controlling for adiposity in black women. Using a cross-sectional study design, 209 urban black women aged ≥ 43 years from the North West Province, South Africa, were included. Multiple regression models were used to explore the relationship between 25(OH)D or PTH and body composition. To explore the association between 25(OH)D or PTH and MetS, a separate variable was created including at least 3 of the MetS criteria, but excluding elevated waist circumference as a diagnostic criterion in a logistic regression model. The majority of the women (69.9%) were overweight or obese and 65.5% of the women had excessive adiposity using the age-specific cut-off points for body fat percentage. All body composition variables were positively associated with PTH, whereas body mass index and waist circumference, but not body fat percentage, had negative associations with 25(OH)D also after adjusting for confounders. Before and after adjusting for age, body fat, habitual physical activity, tobacco use, season of data collection, and estimated glomerular filtration rate, neither 25(OH)D nor PTH showed significant associations with MetS. Although PTH was positively associated and 25(OH)D was negatively associated with adiposity in black women, there was no association between either 25(OH)D or PTH and MetS in this study population, nor did adiposity influence these relationships.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Black People; Body Mass Index; Calcifediol; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Female; Follow-Up Studies; Humans; Hyperparathyroidism; Insulin Resistance; Metabolic Syndrome; Middle Aged; Obesity; Overweight; Parathyroid Hormone; Prevalence; Prospective Studies; Risk; South America; Urban Health; Vitamin D Deficiency

To evaluate the impact of body mass index (BMI) on vitamin D status following ergocalciferol therapy.. A retrospective evaluation of patients aged 18 years and older with a baseline serum 25(OH)D < 30 ng/mL who received prescription ergocalciferol 50 000 IU at any dose between July 2009 and November 2011 was conducted. Patients were included if pre- and posttreatment 25(OH)D levels were available within 3 months of therapy.. Two hundred and thirteen patients were included in the study with 52% having a BMI ≥30 kg/m(2). Thirty-eight different ergocalciferol regimens were prescribed, and the majority of patients (66.2%) received a regimen consisting of 50 000 IU once weekly for variable durations. Mean 25(OH)D levels increased from 18.8 ± 6.6 ng/mL at baseline to 35.0 ± 13.8 ng/mL with 61.0% (n = 130) of patients having attained vitamin D sufficiency, 25(OH)D ≥ 30 ng/mL, with their prescribed ergocalciferol regimen. Obese patients with a BMI ≥30 were less likely to attain vitamin D sufficiency following replacement than patients with a BMI <30 kg/m(2) (52% vs 71%; P = .0161).. Our study demonstrated an overall moderate response rate to replacement therapy with ergocalciferol and considerable variability in vitamin D replacement strategies initiated by primary care providers. Based on our findings, elevated BMI ≥30 kg/m(2) may impact the likelihood of attaining vitamin D sufficiency with ergocalciferol.

Topics: 25-Hydroxyvitamin D 2; Body Mass Index; Case-Control Studies; Ergocalciferols; Female; Humans; Male; Middle Aged; Obesity; Retrospective Studies; Vitamins

Obesity is associated with lower serum concentrations of 25-hydroxyvitamin D (25OHD) and higher intact PTH. The threshold of 25OHD needed to maximally suppress intact PTH has been suggested as a marker of optimal vitamin D status.. In this study, we hypothesized that whereas the obese have a higher serum PTH and lower 25OHD, suppression of serum PTH by 25OHD would be independent of body weight.. We performed a retrospective analysis on 383 women (ages 24-75 y) with a wide range of body weights (43-185 kg) who were stabilized to 1-1.2 g calcium/d for 1 month before blood draw. Body composition, serum PTH, 25OHD, calcium, and creatinine were measured. Locally weighted regression and smoothing scatterplots were used to depict the association between serum PTH and 25OHD. A nonlinear exponential model determined the point for near maximal suppression of PTH by 25OHD.. The point for near maximal suppression of PTH by 25OHD for all women (body mass index, 31.4 ± 7.7 kg/m²) occurred at a 25OHD concentration of 21.7 ng/mL (95% confidence interval, 28-48 ng/mL). No point of maximal suppression was found for nonobese women, yet in the obese women (n = 207; body mass index, >30 kg/m²) suppression of PTH occurred at a 25OHD concentration of 11.1 ng/mL (95% confidence interval, 4.7-17.5 ng/mL).. These results suggest that if PTH is suppressed at a lower serum 25OHD in the obese compared to the entire population, the lower average 25OHD concentrations in the obese may not have the same physiological significance as in the general population.

Topics: 25-Hydroxyvitamin D 2; Adult; Aged; Algorithms; Biomarkers; Body Mass Index; Calcifediol; Female; Humans; Middle Aged; Models, Biological; Nutritional Status; Obesity; Parathyroid Hormone; Retrospective Studies; Vitamin D Deficiency; Young Adult

We aimed to investigate the association between serum 25-hydroxyvitamin D (25(OH)D) and anthropometric indicators of adiposity among Korean preadolescent children aged 7-9 years.. Children aged 7 to 9 from the Ewha Birth & Growth Cohort were followed up from July to August 2011. Serum 25(OH)D concentration was measured using radio immunoassay. We assessed the magnitude of cross-sectional association with vitamin D concentrations and indicators of adiposity [body mass index (BMI), waist circumference (WC), mid-arm circumference (MAC), body fat mass (BFM), percent body fat (PBF), and triceps skinfold thickness (TSF)] using multiple linear and logistic regression analyses adjusted for sex, age, birth order, maternal education, and fruit/fruit juice intake.. Thirty-two (16%) out of a total of 205 children showed an optimal level of serum 25(OH)D, but most children did not reach a sufficient level (<30 ng/mL) even in summer. The level of 25(OH)D was inversely associated with BMI (β=-0.10, p<0.01), WC (β=-0.28, p<0.01), and BFM (β=-0.12, p=0.02) after adjusting for confounding factors and showed marginal boundary with PBF (β=-0.20, p=0.06) and TSF (β=-0.11, p=0.08). Regarding the risk of overweight, a 13% protective effect per 1 ng/mL increase of 25(OH)D was shown even after adjusting for relevant confounding factors (adjusted odds ratio=0.87, 95% confidence interval 0.78-0.98).. We found that the 25(OH)D concentrations were inversely associated with adiposity indices in preadolescent children. This study suggests that adequate vitamin D intake in growing children is crucial to maintain an optimal vitamin D level to prevent obesity and obesity-related health problems later in life.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Body Mass Index; Calcifediol; Child; Child Development; Cohort Studies; Confounding Factors, Epidemiologic; Cross-Sectional Studies; Female; Follow-Up Studies; Humans; Male; Obesity; Overweight; Republic of Korea; Risk; Vitamin D; Vitamin D Deficiency; Waist Circumference

Low vitamin D status is highly prevalent worldwide, and the major determinants are sun exposure and vitamin D intake. We aimed to measure vitamin D status in a sample of overweight/obese adults in Puerto Rico, an area with plenty of sun exposure, and relate it to vitamin D intake, sun exposure and body composition.. Serum 25(OH)D levels (liquid chromatography-tandem mass spectrometry), body weight and fat (bioimpedance), vitamin D intake and sun exposure (questionnaires) were assessed. Analysis included age-adjusted correlations and multivariate regression.. In 98 subjects (66% females; 40-65 years), median serum 25(OH)D levels were 30.7 ng/ml (25-75th percentile 25.0-37.3); 55% had levels >30 ng/ml, 31% had levels between 20 and 30 ng/ml and 14% had levels <20 ng/ml. Total vitamin D intake was 180 IU/day (45-615), and the sun exposure score was 22 (17-27). After adjusting for gender, 25(OH)D levels were significantly correlated with vitamin D intake (r = 0.24, p = 0.018), the sum of sun exposure and vitamin D intake indices (r = 0.34, p = 0.001) and percent body fat (r = -0.25, p = 0.01). After adjusting for age, gender and percent body fat, the sum of sun exposure and vitamin D intake indices remained statistically associated with 25(OH)D levels (β = 1.5, p < 0.01).. In this group of overweight and obese individuals, 25(OH)D was significantly related to vitamin D intake, sun exposure and vitamin D intake indices and percent body fat.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Adult; Anthropometry; Body Composition; Calcifediol; Cross-Sectional Studies; Environmental Exposure; Female; Humans; Male; Middle Aged; Motor Activity; Obesity; Overweight; Puerto Rico; Risk Factors; Skin Pigmentation; Sunlight; Urban Population; Vitamin D Deficiency

The aim of the study was to investigate the concentration of PGRN and other inflammatory cytokines TNF-α, IL-1β, IL-4, IL-6, IL-10, IL-13 and IL-17 in osteopenic and non-osteopenic obese subjects. Bone mineral density in subjects with different PGRN levels were compared to the appraisal of our hypothesis.. A total of 171 obese participants (BMI ≥30) were included in the study. Analysis of body composition was performed with use of Body Composition Analyzer. All blood samples were collected between 8:00 and 10:00 a.m. following an overnight fasting. The circulating levels of TNF-α, PGRN, IL-1β, IL-4, IL-6, IL-10, IL-13, IL-17, PTH, 25-Hydroxy Vitamin D and crosslaps were measured with the EIA method. BMD was measured by use of dual energy X-ray absorptiometery (DXA) at lumbar spine (vertebrae L2-L4) and hip level. Participants were categorized into osteopenic and healthy group according to the World Health Organization (WHO) criteria. Of 171 participants, 51 (29.82 %) were osteopenic and 120 (70.17%) were healthy.. We found significantly higher concentrations of crosslaps, IL-17, IL-6, TNFα and IL-4 and lower concentrations of IL-13, IL-10, PGRN and free fat mass in osteopenic group. With raising the PGRN level, the concentrations of IL-13, IL-10 and 25-(OH) vitamin D were increased and the concentration of TNFα and IL-17 were decreased. Our results demonstrated that the density of bone at both sites of lumbar spine (L2-L4) and hip region was highest in 4th quartile and lowest in first quartile of categorized PGRN concentration. The bone status was gradually improved with raising the PGRN level in parallel at lumbar spine (L2-L4) and hip regions.. Based on the pathway of effect of TNFα on bone metabolism, it appears that PGRN acts on the bone with mechanisms involving TNFR signaling, disturbance and TNFα performance, similar to the results that have been found in animal model study.

Topics: 25-Hydroxyvitamin D 2; Adult; Biomarkers; Body Composition; Bone Density; Bone Diseases, Metabolic; Collagen; Female; Hip; Humans; Inflammation; Intercellular Signaling Peptides and Proteins; Interleukins; Iran; Lumbosacral Region; Male; Middle Aged; Obesity; Parathyroid Hormone; Peptide Fragments; Progranulins; Protein Precursors; Receptors, Tumor Necrosis Factor; Spine; Tumor Necrosis Factor-alpha; Young Adult

Recent studies have suggested a beneficial effect of vitamin D and calcium on adipocyte metabolism and the metabolic profile. Our objective was to examine associations of vitamin D intake, calcium and dairy products as well as serum 25(OH)D concentration with adiposity measures and adipocyte size in women. Omental and subcutaneous adipose tissue samples were obtained from 43 women undergoing gynecological surgeries. Adipocyte size was measured using adipocyte suspensions from collagenase-digested fat tissues. Total and visceral adiposity were assessed by dual-energy X-ray absorptiometry and computed tomography, respectively. Serum 25(OH)D was measured by radioimmmunoassay. Dietary intakes were assessed using a food frequency questionnaire. Women consuming two or more dairy product portions daily had smaller adipocytes in the omental depot compared to women consuming less than two portions daily (79 ± 12 vs. 94 ± 16 µm, P ≤ 0.01). Dietary intakes of calcium (r = -0.55) and vitamin D (r = -0.43) as well as serum 25(OH)D (r = -0.35) were also inversely and significantly associated with omental adipocyte size (P ≤ 0.05 for all). Dietary vitamin D intake was inversely associated with visceral adipose tissue area (r = -0.34, P ≤ 0.05). Serum 25(OH)D was also inversely associated with visceral adipose tissue area (r = -0.32) as well as with total adipose tissue area (r = -0.44), subcutaneous adipose tissue area (r = -0.36), BMI (r =-0.43) and total body fat mass (r = -0.41, P ≤ 0.05 for all). In conclusion, elevated dietary vitamin D intake and serum 25(OH)D values are related to lower visceral adiposity and omental adipocyte size in women.

Topics: 25-Hydroxyvitamin D 2; Absorptiometry, Photon; Adipocytes; Adiposity; Adult; Body Mass Index; Calcifediol; Calcium, Dietary; Cell Size; Cross-Sectional Studies; Dairy Products; Female; Humans; Intra-Abdominal Fat; Middle Aged; Obesity; Subcutaneous Fat, Abdominal; Surveys and Questionnaires; Tomography, X-Ray Computed; Vitamin D

Topics: 25-Hydroxyvitamin D 2; Adult; Antarctic Regions; Calcifediol; Dietary Supplements; Female; Humans; Male; Models, Biological; Nutrition Policy; Nutritional Requirements; Obesity; Reproducibility of Results; Vitamin D; Vitamin D Deficiency

An association between vitamin D status and sarcopenia has not been shown in a community-dwelling cohort, despite the well-documented relationship between vitamin D status and falls.. Our objective was to investigate whether vitamin D level is associated with sarcopenia in older Koreans.. The Fourth Korea National Health and Nutrition Examination Survey in the Korean population was conducted in 2009.. Participants included 1380 men and 1789 women aged 50 yr or older.. Serum 25-hydroxyvitamin D [25(OH)D] and PTH levels were measured. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight that was less than 2 sd below the sex-specific mean for young adults. Obesity was defined as a body mass index (BMI) of 27.5 kg/m(2) or higher.. 25(OH)D level correlated negatively with appendicular fat mass and positively with appendicular skeletal mass. The groups with sarcopenic obesity and sarcopenia only had lower 25(OH)D levels than did the nonsarcopenia groups. However, 25(OH)D levels did not differ between the sarcopenic obesity and sarcopenia groups. After adjustment for age, sex, BMI, and lifestyle factors, compared with those in the lowest quartile of 25(OH)D level, participants in the highest quartile had an odds ratio for sarcopenia of 0.47 (95% confidence interval = 0.30-0.73; P for trend = 0.001). There was no association between PTH and sarcopenia after adjustment of BMI.. Vitamin D levels were significantly lower in subjects with sarcopenia than in those without, regardless of obesity. We found a strong inverse association between 25(OH)D level and sarcopenia in the older Korean population.

Topics: 25-Hydroxyvitamin D 2; Aged; Asian People; Body Mass Index; Calcifediol; Cross-Sectional Studies; Female; Health Surveys; Humans; Male; Middle Aged; Nutrition Surveys; Obesity; Parathyroid Hormone; Republic of Korea; Risk Factors; Sarcopenia; Vitamin D Deficiency

Low levels of vitamin D and excess body weight are both factors associated with increased risk of cancer. The increased risk seems to be proportional to the increase in BMI, and to decrease in serum 25-hydroxyvitamin D (25(OH)D) level. Our earlier investigations suggest that serum 25(OH)D levels decrease with increasing BMI. Although the connection between cancer risk, BMI and vitamin D status might be arbitrary, it has not been discussed in the literature so far. In this study, we analyze data published in current meta-analysis, prospective studies, and systematic reviews on cancer-specific risk attributed to high BMI and low vitamin D status. The contribution of low 25(OH)D levels associated with high BMI to increased cancer risk was calculated for 13 vitamin-D-sensitive cancers with a focus on colorectal and breast cancer as the most frequently studied vitamin-D-sensitive cancer types. Our study suggests that a low vitamin D status may explain at least 20% of the cancer risk attributable to high BMI. The contribution of low 25(OH)D to the increased cancer risk with increasing BMI may be different for different cancer types. Thus, we find 40% for breast cancer, and 26 and 75% for colorectal cancer in men and women, respectively.

Topics: 25-Hydroxyvitamin D 2; Adult; Body Mass Index; Breast Neoplasms; Calcifediol; Colorectal Neoplasms; Female; Humans; Male; Middle Aged; Neoplasms; Obesity; Prevalence; Risk Factors; Sex Factors; Vitamin D Deficiency; Young Adult

Topics: 25-Hydroxyvitamin D 2; Alkaline Phosphatase; Biomarkers; Calcium; Female; Gastric Bypass; Humans; Hyperparathyroidism, Secondary; Laparoscopy; Obesity; Postoperative Care; Vitamin D; Vitamin D Deficiency

Twenty-three obese subjects who had undergone intestinal bypass operation (end-to-side jejunostomy) were studied with respect to vitamin D and other indices of calcium metabolism. Group 1 (11 patients) was examined before and one year after operation. Group 2 (12 patients, bypass operated two to seven years earlier was investigated twice with an interval of one year. The two groups were comparable. Bone mineral content and alkaline phosphatases were unchanged during the study in both groups. Bone phosphorus/hydroxyproline ratio was high postoperatively indicating a high degree of bone mineralisation. Serum calcium declined rapidly in group 1 to a constant level, which was maintained in group 2. The serum levels of iPTH and 1,25(OH)2D did not change within each group, but combining the two groups demonstrated an increase/decrease in iPTH/1,25(OH)2D over the years. The findings suggest that factors other than 1,25(OH)2D and iPTH are involved in calcium metabolism in such patients. The findings do not justify routine administration to such patients of high potency vitamin D derivatives, f.ex. 1 alpha-OH-D3.

Topics: 25-Hydroxyvitamin D 2; Adult; Bone and Bones; Calcium; Ergocalciferols; Female; Humans; Ileum; Jejunum; Longitudinal Studies; Male; Middle Aged; Minerals; Obesity; Parathyroid Hormone; Postoperative Period; Vitamin D

A 48-year-old woman underwent jejunoileal bypass surgery for obesity while hypercalcemic. Three years later, she developed symptomatic osteomalacia impairing her daily activities. Bone biopsy confirmed the clinical diagnosis of osteomalacia, and treatment with 8000 U daily of vitamin D and milk resulted in striking improvement of clinical symptoms and resolution of her osteomalacia both chemically and histologically. The patient, however, again became hypercalcemic and a parathyroid adenoma was subsequently removed with restoration of serum calcium values to normal. Neither the occurrence and successful treatment of gross symptomatic osteomalacia consequent to jejunoileal bypass surgery, nor the obscuration of primary hyperparathyroidism by osteomalacia has been hitherto well documented in the United States.

Topics: 25-Hydroxyvitamin D 2; Biopsy; Bone and Bones; Dihydroxycholecalciferols; Ergocalciferols; Female; Humans; Hyperparathyroidism; Ileum; Jejunum; Middle Aged; Obesity; Osteomalacia; Postoperative Complications; Vitamin D