Vitamin D in overweight/obese women and its relationship with dietetic and anthropometric variables

Vitamin D status and its relationship with obesity indicators in Moroccan adult women

Background: Although vitamin D deficiency has been studied in various populations, there are few data on its prevalence and associated factors among Moroccan women. Aim: To determine the prevalence of vitamin D deficiency and investigate its association with body mass index (BMI), waist circumference, and serum concentrations of parathyroid hormone, calcium, and phosphorus in a sample of Moroccan adult women. Methods: This is a cross-sectional study conducted at Mohammed V Military Hospital of Instruction, Rabat. Anthropometric measurements and biochemical analyses were performed using standard procedures Results: A total of 714 women aged 18-65 years participated in this study. The overall prevalence of vitamin D deficiency was 74.4%. Approximately 24% and 51% of women had severe and moderate vitamin D deficiency, respectively. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were inversely correlated with BMI in vitamin D-deficient subjects (P = 0.036) and with parathyroid hormone 1-84 (PTH1-84) levels in the study sample (P = 0.010). PTH1-84 concentrations were greater among overweight/obese individuals compared to their non-overweight peers (P = 0.001) and tended to be higher among vitamin D-deficient women than vitamin D-sufficient women (P = 0.053). Conclusion: This study showed a very high prevalence of vitamin D deficiency in this sample of Moroccan women. Lower serum 25(OH)D levels were associated with increased BMI in vitamin D-deficient women and with elevated PTH1-84 levels among the study sample. Although these findings come from a convenience sample of women that attended a nutrition clinic, they underscore the urgent need to develop public health interventions to improve women's vitamin D status.

Obesity and Breast Cancer: Interaction or Interference with the Response to Therapy?

Background: Aromatase inhibitors (AI) are widely used for treating hormone-sensitive breast cancer (BC). Obesity, however, due to aromatase-mediated androgen conversion into estradiol in the peripheral adipose tissue, might impair AI inhibitory capacity. We aimed at identifying a cut-off of body mass index (BMI) with significant prognostic impact, in a cohort of stage I-II BC patients on systemic adjuvant therapy with AI. Methods: we retrospectively evaluated routinely collected baseline parameters. The optimal BMI cut-off affecting disease-free survival (DFS) in AI-treated BC patients was identified through maximally selected rank statistics; non-linear association between BMI and DFS in the AI cohort was assessed by hazard-ratio-smoothed curve analysis using BMI as continuous variable. The impact of the BMI cut-off on survival outcomes was estimated through Kaplan−Meier plots, with log-rank test and hazard ratio estimation comparing patient subgroups. Results: A total of 319 BC patients under adjuvant endocrine therapy and/or adjuvant chemotherapy were included. Curve-fitting analysis showed that for a BMI cut-off >29 in AI-treated BC patients (n = 172), DFS was increasingly deteriorating and that the impact of BMI on 2-year DFS identified a cut-off specific only for the cohort of postmenopausal BC patients under adjuvant therapy with AI. Conclusion: in radically resected hormone-sensitive BC patients undergoing neoadjuvant or adjuvant chemotherapy and treated with AI, obesity represents a risk factor for recurrence, with a significantly reduced 2-year DFS.

Secondary Hyperparathyroidism Before and After Bariatric Surgery: a Prospective Study with 2-Year Follow-Up

PURPOSE

Secondary hyperparathyroidism (SHPT) is linked to obesity. Bariatric surgery may be associated with calcium and vitamin D deficiencies leading to SHPT. This study aimed to detect the prevalence of SHPT before and after bariatric surgery.

METHODS

This prospective study assessed the prevalence of SHPT after sleeve gastrectomy (SG, n = 38) compared to one-anastomosis gastric bypass (OAGB, n = 86). All patients were followed up for 2 years. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry.

RESULTS

Of the 124 patients, 71 (57.3%) were females, and 53 (42.7%) were males, with a mean age of 37.5 ± 8.8 years. Before surgery, 23 patients (18.5%) suffered from SHPT, and 40 (32.3%) had vitamin D deficiency. The prevalence of SHPT increased to 29.8% after 1 year and 36.3% after 2 years. SHPT was associated with lower levels of vitamin D and calcium and higher reduction of BMD in the hip but not in the spine. After 2 years, SHPT was associated with a significantly lower T-score in the hip. SHPT and vitamin D deficiency were significantly more common in patients subjected to OAGB compared to SG (p = 0.003, and p < 0.001, respectively). There is a strong negative correlation between vitamin D levels and parathormone levels before and after surgery.

CONCLUSION

Prevalence of SHPT is high in obese patients seeking bariatric surgery, especially with lower vitamin D levels. Bariatric surgery increases the prevalence of SHPT up to 2 years. Gastric bypass is associated with a higher risk of developing SHPT compared to SG.

Mechanisms Linking Vitamin D Deficiency to Impaired Metabolism: An Overview

Vitamin D deficiency is a common health problem worldwide. Despite its known skeletal effects, studies have begun to explore its extra-skeletal effects, that is, in preventing metabolic diseases such as obesity, hyperlipidemia, and diabetes mellitus. The mechanisms by which vitamin D deficiency led to these unfavorable metabolic consequences have been explored. Current evidence indicates that the deficiency of vitamin D could impair the pancreatic β-cell functions, thus compromising its insulin secretion. Besides, vitamin D deficiency could also exacerbate inflammation, oxidative stress, and apoptosis in the pancreas and many organs, which leads to insulin resistance. Together, these will contribute to impairment in glucose homeostasis. This review summarizes the reported metabolic effects of vitamin D, in order to identify its potential use to prevent and overcome metabolic diseases.

Factors Associated with Serum Vitamin D Metabolites and Vitamin D Metabolite Ratios in Premenopausal Women

The most representative indicator of vitamin D status in clinical practice is 25(OH)D3, but new biomarkers could improve the assessment of vitamin D status and metabolism. The objective of this study is to investigate the association of serum vitamin D metabolites and vitamin D metabolite ratios (VMRs) with potentially influential factors in premenopausal women. This is a cross-sectional study based on 1422 women, aged 39-50, recruited from a Madrid Medical Diagnostic Center. Participants answered an epidemiological and a food frequency questionnaire. Serum vitamin D metabolites were determined using an SPE-LC-MS/MS platform. The association between participant's characteristics, vitamin D metabolites, and VMRs was quantified by multiple linear regression models. Mean 25(OH)D3 concentration was 49.2 + 18.9 nmol/L, with greater deficits among obese, nulliparous, dark-skinned women, and with less sun exposure. A lower R2 ratio (1,25(OH)2D3/25(OH)D3) and a higher R4 (24,25(OH)2D3/1,25(OH)2D3) were observed in nulliparous women, with high sun exposure, and those with low caloric intake or high consumption of calcium, vitamin D supplements, or alcohol. Nulliparous women had lower R1 (25(OH)D3/Vit D3) and R3 (24,25(OH)2D3/25(OH)D3), and older women showed lower R3 and R4. Vitamin D status modified the association of the VMRs with seasons. VMRs can be complementary indicators of vitamin D status and its endogenous metabolism, and reveal the influence of certain individual characteristics on the expression of hydroxylase enzymes.

Association between Cardiometabolic risk factor and responsiveness to vitamin D supplementation: a new approach using artificial neural network analysis

BACKGROUND

There are increasing data highlighting the effectiveness of vitamin D supplementation in the treatment of vitamin D deficiency. But individuals vary in their responsiveness to vitamin D supplementation. In this study, the association between several cardiometabolic risk factors and the magnitude of response to vitamin D supplementation (change in vitamin D level) was investigated using a novel artificial neural networks (ANNs) approach.

METHODS

Six hundred eight participants aged between 12 to 19 years old were recruited to this prospective interventional study. Nine vitamin D capsules containing 50,000 IU vitamin D/weekly were given to all participants over the 9 week period. The change in serum 25(OH) D level was calculated as the difference between post-supplementation and basal levels. Suitable ANNs model were selected between different algorithms in the hidden and output layers and different numbers of neurons in the hidden layer. The major determinants for predicting the response to vitamin D supplementation were identified.

RESULTS

The sigmoid in both the hidden and output layers with 4 hidden neurons had acceptable sensitivity, specificity and accuracy, assessed as the area under the ROC curve, was determined in our study. Baseline serum vitamin D (30.4%), waist to hip ratio (10.5%), BMI (10.5%), systolic blood pressure (8%), heart rate (6.4%), and waist circumference (6.1%) were the most important factors in predicting the response to serum vitamin D levels.

CONCLUSION

We provide the first attempt to relate anthropometric specific recommendations to attain serum vitamin D targets. With the exception of cardiometabolic risk factors, the relative importance of other factors and the mechanisms by which these factors may affect the response requires further analysis in future studies (Trial registration: IRCT201509047117N7; 2015-11-25; Retrospectively registered).

Vitamin D status of overweight and obese Bangladeshi adults

Background:

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

Objective:

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

Subjects and Methods:

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

Results:

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

Conclusions:

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

Vitamin D in physiological and pathological aging: Lesson from centenarians

Vitamin D is a secosteroid hormone that exerts a pleiotropic action on a wide spectrum of tissues, apparatuses and systems. Thus, vitamin D has assumed an increasingly dominant role as a key determinant of biological mechanisms and specific clinical conditions. Older people frequently present vitamin D deficiency, a status potentially influencing several mechanisms responsible for different age-related diseases. Centenarians symbolize the ideal model for investigating the peculiar traits of longevity, as they have reached an age close to the estimated limit of the human lifespan. Interestingly, despite the profound heterogeneity of centenarians in terms of health status, all these people share the same condition of severe vitamin D deficiency, suggesting that they may have implemented a number of adaptive strategies to cope with the age-related physiological derangement of vitamin D metabolism. The lesson deriving from centenarians' experience suggests that: i) severe vitamin D deficiency does not preclude the possibility of reaching extreme longevity, ii) strategies to prevent hypovitaminosis D may be useful to slow down the processes of "fragilization" occurring in aged people, iii) beneficial effects of vitamin D supplementation need to be confirmed regarding longevity.

Antifibrotic Effects of 1,25(OH)2D3 on Nonalcoholic Steatohepatitis in Female Mice

BACKGROUND

Postmenopausal women have a higher risk of nonalcoholic steatohepatitis (NASH) along with an increase in age, and vitamin D deficiency occurs in some patients with NASH.

AIM

We performed ovariectomy (OVX) surgery on female mice to mimic menopause, fed them a choline-deficient high-fat (CDHF) diet to induce NASH, and then investigated the effects of treatment with 1,25(OH)₂D₃.

METHODS

Seven-week-old C57BL/6J female mice were separated into five experimental groups: SHAM, OVX, and OVX + intraperitoneal (i.p.) injection of 1,25(OH)₂D₃ (0.0008, 0.004, and 0.02 μg/kg). All groups were fed a CDHF diet for 8 weeks. Injections took place twice per week throughout the experimental period. Blood samples and liver tissue were collected for analyzing liver histological changes, serum biochemical indicators of hepatic function, and hepatic genes associated with fibrosis.

RESULTS

Supplementation of 1,25(OH)₂D₃ in CDHF-diet mice showed decreased serum levels of ALT, AST, indicating the improvement in overall liver function, and suppressed histological NASH regarding fibrosis stage, lobular inflammation, and steatosis compared to the OVX group. Primary fibrotic markers of TGF-β, TIMP-1, α-SMA, and COL1A1 were significantly lower in the 1,25(OH)₂D₃ groups than in the OVX group. Furthermore, down-regulated levels of SMAD2 and SMAD3 were also observed in 1,25(OH)₂D₃ groups.

CONCLUSION

Supplementation of 1,25(OH)₂D₃ may ameliorate liver fibrosis and improve liver function in OVX mice with NASH induced by a CDHF diet, suggesting the therapeutic effects on postmenopause with NASH.

[Vitamin D deficiency in Spanish population. Importance of egg on nutritional improvement]

INTRODUCTION

Vitamin D is an essential nutrient whose deficiency has been associated with the risk of various chronic diseases such as osteoporosis, hypertension, cardiovascular disease, diabetes, some types of cancer and even overweight and obesity. Although vitamin D can be synthesized at the skin from exposure to sunlight, this source is not always sufficient to meet the needs. For example, the use of sunscreen or the low exposition to the sunlight limits the syntheses. In fact, studies have found that at least half of the Spanish population has vitamin D deficits. Therefore, the dietary contribution is fundamental. Although there are different foods fortified in this vitamin, few products are natural source of it, as fatty fish and eggs. However, according to different studies carried out in the Spanish population, there is a low consumption of this food group. In this way, it would be advisable to promote egg consumption among the population, since this food, in addition to having many nutrients, contains a high amount of vitamin D, which contributes to avoid the appearance of deficiencies and the consequences health consequences that this implies.

Role of Hypovitaminosis D in the Pathogenesis of Obesity-Induced Insulin Resistance

Obesity and type 2 diabetes have both rapidly increased during the last decades and are continuing to increase at an alarming rate worldwide. Obesity and impaired glucose homeostasis are closely related, and during the last decades of investigation about vitamin D, several clinical and epidemiological studies documented an inverse correlation between circulating vitamin D levels, central adiposity and the development of insulin resistance and diabetes. The insufficient sun exposure and outdoor activities of obese individuals, the storage of vitamin D in adipose tissue, because of its lipophilic properties, and the vitamin D-mediated modulation of adipogenesis, insulin secretion, insulin sensitivity and the immune system, are the main reasons for the close relationship between obesity, glucose homeostasis and hypovitaminosis D. Then objective of this review is to explore the pathophysiological mechanism(s) by which vitamin D modulates glycemic control and insulin sensitivity in obese individuals.

Pandemic of Vitamin D Deficiency: Cardiometabolic Concern or Skeletal Biochemical Abnormality?

CONTEXT

Biochemical Vitamin D deficiency is said to be present universally in recent times. However, its effect is more profound in modulation of anthropometric and biochemical risk factors of various chronic metabolic disorders rather than its influence on bone mineral abnormalities. The present study was undertaken to compare various anthropometric and biochemical parameters including basic bone mineral biochemistry in various strata of Vitamin D status.

MATERIALS AND METHODS

A population based study was done in the rural area of West Bengal comprising 405 people (initially targeted 400) to look for various anthropometric and biochemical parameters.

RESULTS

Anthropometric metabolic markers like BMI, WC, waist to height ratio and biochemical parameters like total cholesterol, LDL, TG, insulin, ALT, FPG were statistically significantly higher in vitamin D deficient (<20 ng/ml) (n = 228) subjects compared to Vitamin D non-deficient subjects (≥20 ng/ml) (n = 177) which persisted even after adjustment for BMI except for FPG. The difference was similarly present when severely Vitamin D deficient (<10 ng/ml) (n = 39) subjects were compared to Vitamin D sufficient subjects (≥30 ng/ml) (n = 38) and persisted after adjustment for BMI except for FPG. However, WHR, blood pressure (both systolic and diastolic), HbA1c, HDL, AST, Uric acid, freeT4, TSH, HOMA-IR were not different in both the above-mentioned comparisons. Metabolic syndrome was statistically significantly lower in vitamin D non-deficient subjects. Though iPTH was statistically significantly higher in the low vitamin D cohorts in both the comparisons, bone mineral markers like serum calcium, phosphorus and alkaline phosphatase were not different even when severely vitamin D deficient subjects were compared to vitamin D sufficient subjects.

CONCLUSION

Pandemic of vitamin D deficiency is more likely to be associated with cardio-metabolic risk factors than biochemical bone mineral abnormality.

Association of Vitamin D Status with Chronic Disease Risk Factors and Cognitive Dysfunction in 50⁻70 Year Old Adults

Vitamin D deficiency/insufficiency has been primarily associated with skeletal disorders, however, since vitamin D receptors are found on multiple types of cells, there is also a link to increased chronic disease risk and all-cause mortality. The aim of this study was to examine whether deficient/insufficient vitamin D levels are associated with risk factors of chronic diseases and cognitive dysfunction in 50 to 70 year old adults. Participants completed the health status, three-day dietary record and vitamin D food frequency, sun exposure, and international physical activity questionnaires. Cognitive function of the participants was assessed using the Automated Neuropsychological Assessment Metrics while body composition (percent body fat, android/gynoid ratio) was assessed using Dual Energy X-ray Absorptiometry. Applanation tonometry was used to obtain pressure wave forms at the radial artery to examine arterial stiffness and central pressures. A fasting blood draw was taken to measure vitamin D, blood lipid and glucose levels. Fifty percent of the participants (36/72) were vitamin D deficient/insufficient. Individuals in the low physical activity (PA) group had lower serum vitamin D concentration compared to those in the high PA group (p = 0.04). Moreover, serum vitamin D levels were negatively related to risk factors of chronic diseases; blood glucose (r = -0.38; p = 0.01), triglycerides (r = -0.27; p = 0.02), and android/gynoid ratio (r = -0.32; p = 0.01). Deficient/insufficient vitamin D levels are linked to the risk factors of chronic diseases in men and women aged 50 to 70 years.

Vitamin D and Metabolic Diseases: Growing Roles of Vitamin D

Vitamin D, a free sunshine vitamin available for mankind from nature, is capable to avert many health-related critical circumstances. Vitamin D is no more regarded as a nutrient involved in bone metabolism alone. The presence of vitamin D receptor in a number of tissues implies that vitamin D has various physiological roles apart from calcium and phosphorus metabolism. Low serum vitamin D has been found to be associated with various types of metabolic illness such as obesity, diabetes mellitus, insulin resistance, cardiovascular diseases including hypertension. Various studies reported that vitamin D insufficiency or deficiency in linked with metabolic syndrome risk. This review focuses on various metabolic diseases and its relationship with serum vitamin D status.

Excessive abdominal adiposity and body fat are associated with lower serum vitamin D levels: A population-based study

ABSTRACT Objective To estimate the prevalence of 25-hydroxyvitamin D deficiency and to analyze factors associated with lower serum vitamin levels in Brazilian adults. Methods A cross-sectional, population-based study consisted of 626 adult individuals of both sexes living in the urban area of Viçosa, Minas Gerais. The dependent variable used was the serum level of 25-hydroxyvitamin D and the independent variables were sociodemographic, anthropometric and body composition variables. The associations among the variables were verified using simple and multiple linear regression models, considering alpha lower than 0.05 for the input in the final model. Results The prevalence of 25-hydroxyvitamin D deficiency was 14.4% and the prevalence was 42.0%. Excess abdominal fat was higher in subjects with 25-hydroxyvitamin D sufficiency. The serum level of 25-hydroxyvitamin D was 30.34±9.85ng/ml. Body adiposity was higher in men with vitamin insufficiency. Negative associations were observed between serum 25-hydroxyvitamin D levels and age, educational level, body adiposity (p=0.028) and abdominal adiposity (p=0.023). Conclusion Our results showed that excess body and abdominal adiposity are strong predictors of alterations in the serum vitamin D levels, thus public policies for prevention and treatment in this population are essential.

Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study

Introduction

Vitamin D (vit D) deficiency has defined as a health problem worldwide. World Health Organization (WHO) has declared that obesity is an epidemic of the 21^st century. Previous studies have shown that obesity may increase the risk of Vit D deficiency. Furthermore, other studies have demonstrated that vit D insufficiency was accompanied with higher risk of type 2 diabetes, cardiovascular diseases, hypertension, and obesity. The aim of this study was to survey the effect of vit D supplementation on weight loss among overweight and obese women aged 20-40 years in Isfahan.

Methods

This double-blind clinical trial was done on 50 overweight and obese women who were divided into two groups, in which one group received vit D supplements and the other group received placebo. Intervention group received vit D with dozes 50,000 IU/w for 6 weeks. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), fasting blood sugar (FBS), insulin (ins), homeostasis model assessment of ins resistance (IR), C-reactive protein (CRP), height, weight (WT), waist circumference (WC), hip circumference (HC), and blood pressure (BP) were measured before and after intervention.

Results

After using vit D supplementation for 6 weeks, WT, WC, and body mass index (BMI) were decreased significantly and serum vit D increased significantly compared to control group (P < 0.001). Other factors including TC, TG, LDL-c, HDL-c, FBS, CRP, ins, IR, and waist to hip ratio (WHR) did not change significantly (P > 0.05).

Conclusions

After 6 weeks of intervention, the means of WT, BMI, WC, and HC decreased significantly. Previous studies have shown that vit D deficiency was more prevalence in obese people and there was an inverse association among vit D with BMI and WC. The relationship between vit D and lipid profiles such as glycemic indexes, anthropometric indexes, CRP, and BP is not clear and needs more study in the future.

Evaluating Vitamin D Status in Pre- and Postmenopausal Type 2 Diabetics and Its Association with Glucose Homeostasis

Background

Type 2 Diabetes Mellitus (T2DM) and menopause are associated with vitamin D status. Oestrogen decline during menopausal stages promotes hypovitaminosis D. However, the interplay between vitamin D, menopause, lifestyle, and T2DM cannot be overlooked. This study assessed vitamin D status among pre- and postmenopausal T2DM women and determined its association with glycemic control and influence of lifestyle habits on hypovitaminosis D.

Methods

This cross-sectional study was conducted at the Komfo Anokye Teaching Hospital, Kumasi, Ghana. Structured questionnaires were administered to 192 T2DM women; blood samples were collected for estimation of 25(OH) D and insulin using ELISA. Fasting blood glucose (FBG), lipid profile, glycated haemoglobin (HbA1c), and calcium were measured. Statistical analyses were performed using Graphpad Prism 6.

Results

The prevalence of vitamin D inadequacy was 92.2%. Hypovitaminosis D was more prevalent among the postmenopausal T2DM women (63.8% versus 58.2%). Hypovitaminosis D significantly associated with insulin [R² = 0.01760, p = 0.0008], HbA1c [R² = 0.3709, p = <0.0001], and FBG [R² = 0.3465, p = 0.0001] in only the postmenopausal women.

Conclusion

Vitamin D deficiency is prevalent in pre- and postmenopausal T2DM but higher among postmenopausal women. Adequate vitamin D levels in both groups were associated with improved glucose control while hypovitaminosis D in the postmenopausal women was related to poorer glucose control. Vitamin D screening should be incorporated into management plan for T2DM to serve as an early tool for prevention of vitamin D deficiency.

Body composition and metabolic profile in adults with vitamin D deficiency

ABSTRACT Objective: To investigate the body composition and metabolic profile in individuals in terms of different concentrations of serum vitamin D, ranging from deficiency to sufficiency. Methods: A cross-sectional study of 106 adults of both genders, who were divided into three groups according to vitamin D levels: deficiency: <20ng/mL; insufficiency: 20-29.9ng/mL; and sufficiency: 30-100ng/mL. Anthropometric evaluation included weight, height, and body circumferences. Fat mass and lean mass were assessed using the Tetrapolar bioelectrical impedance method. Clinical and biochemical evaluations were also carried out. Insulin resistance was estimated using the Homeostasis Model Assessment Insulin index. Results: The analysis showed that the main alterations in individuals in the vitamin D deficiency group were higher triglycerides, very low density lipoprotein - cholesterol, fasting blood glucose, insulin, glycated hemoglobin, body mass index, body fat percentage, lean mass percentage, waist circumference, and Homeostasis Model Assessment Insulin than those of the vitamin D sufficient group (p<0.05). Conclusion: It was found that vitamin D deficiency causes important body composition and metabolic changes, which may lead to diseases such as diabetes Mellitus and metabolic syndrome.

Low vitamin D status and obesity: Role of nutritionist

Low vitamin D status and obesity have concomitantly reached epidemic levels worldwide. Up to now the direction of the association between low vitamin D status and obesity, the exact mechanisms responsible for this association and the clinical usefulness to increase vitamin D status for reducing adiposity still warrant further evaluation. The aim of the present review was to examine the current evidence linking low vitamin D status and obesity in relation to the role of the nutritionist. On the one side, considering obesity as a causal factor, low sun exposure in obese individuals due to their sedentary lifestyle and less outdoor activity, vitamin D sequestration in adipose tissue, and volumetric dilution of ingested or cutaneously synthesized vitamin D₃ in the large fat mass of obese patients, might represent some of the factors playing a major role in the pathogenesis of the low vitamin D status. On the other side, the expression of both vitamin D₃ receptors and enzymes responsible for vitamin D₃ metabolism in adipocytes depicted a role for the low vitamin D status per se in the development of obesity by modulating adipocyte differentiation and lipid metabolism. Nutritionists need to accurately address the aspects influencing the low vitamin D status in obesity and the vitamin D supplementation in obese individuals.

Vitamin D status and its association with insulin resistance among type 2 diabetics: A case -control study in Ghana

Background

Vitamin D plays a major role in physiological processes that modulate mineral metabolism and immune function with probable link to several chronic and infectious conditions. Emerging data suggests a possible influence of vitamin D on glucose homeostasis. This study sought to provide preliminary information on vitamin D status among Ghanaian type 2 diabetics and assessed its association with glucose homeostasis.

Methods

In a case control study, 118 clinically diagnosed Type 2 Diabetes Mellitus (T2DM) patients attending Diabetic Clinic at the Nkawie Government Hospital were enrolled between October and December 2015. Hundred healthy non-diabetics living in Nkawie district were selected as controls. Structured questionnaires were administered to obtain socio-demographic data. Venous blood samples were taken from both cases and controls to estimate their FBG, Lipid profile spectrophotometrically and IPTH, 25OHD by ELISA. Statistical analyses were performed using SPSS v20.0 Statistics.

Results

The average age of the study participants was 58.81years for cases and 57.79year for controls. There was vitamin D deficiency of 92.4% among T2DM cases and 60.2% among the non diabetic controls. Vitamin D deficiency did not significantly associate with HOMA-β [T2DM: r² = 0.0209, p = 0.1338 and Control: r² = 0.0213, p = 0.2703] and HOMA-IR [T2DM: r² = 0.0233, p = 0.1132 and Control: r² = 0.0214, p = 0.2690] in both the controls and the cases.

Conclusion

Vitamin D deficiency is prevalent in both T2DM and non-diabetics. There is no association between vitamin D deficiency and insulin resistance or beta cell function in our study population. Vitamin D supplementation among type 2 diabetics is recommended.

Association of serum 25-hydroxyvitamin D3 with adipokines and inflammatory marker in persons with prediabetes mellitus

BACKGROUND

The association of vitamin D status and inflammation prediabetes mellitus (PreDM) individuals has not been investigated. We investigated the association of serum 25-hydroxyvitamin D₃ (25(OH) D₃) with adipokines and inflammatory markers in persons with PreDM.

METHODS

In this cross-sectional study, we stratified 418 nondiabetic subjects as having PreDM or normal fasting glucose (NFG), and divided PreDM or NFG subjects into vitamin D sufficient, vitamin D insufficient and vitamin D deficient subgroups. 25(OH) D₃ concentrations were determined by HPLC. Serum tumor necrosis factor-α (TNF-α), interleiukin-6 (IL-6) and high-sensitivity C-reactive protein (hs-CRP), adiponectin, leptin and resistin were measured by ELISA.

RESULTS

In the PreDM group, compared with those in the vitamin D sufficient subgroup, vitamin D insufficient subgroup and vitamin D deficient subgroup had higher concentrations of hs-CRP and leptin (P<0.05). In the PreDM-deficient or PreDM-insufficient subgroup, mean hs-CRP and leptin concentration was higher than in the PreDM-sufficient, NFG-deficient, NFG-insufficient and NFG-sufficient subgroups (P<0.05). Serum 25(OH) D₃ concentrations were inversely associated with hs-CRP and leptin concentrations after adjusted the BMI only in the PreDM group (P<0.05). At the multivariate analysis, hs-CRP and leptin were the major determinant of 25(OH) D₃ concentration (β=-0.174 and β=-0.171, respectively).

CONCLUSIONS

25(OH) D₃ status in PreDM individuals was inversely correlated with concentrations of hs-CRP and leptin, suggesting their involvement in the inflammation response between vitamin D status and PreDM.

A vitamin D pathway gene-gene interaction affects low-density lipoprotein cholesterol levels

Much evidence suggests an association between vitamin D deficiency and chronic diseases such as obesity and dyslipidemia. Although genetic factors play an important role in the etiology of these diseases, only a few studies have investigated the relationship between vitamin D-related genes and anthropometric and lipid profiles. The aim of this study was to investigate the association of three vitamin D-related genes with anthropometric and lipid parameters in 542 adult individuals. We analyzed the rs2228570 polymorphism in the vitamin D receptor gene (VDR), rs2134095 in the retinoid X receptor gamma gene (RXRG) and rs7041 in the vitamin D-binding protein gene (GC). Polymorphisms were genotyped by TaqMan allelic discrimination. Gene-gene interactions were evaluated by the general linear model. The functionality of the polymorphisms was investigated using the following predictors and databases: SIFT (Sorting Intolerant from Tolerant), PolyPhen-2 (Polymorphism Phenotyping v2) and Human Splicing Finder 3. We identified a significant effect of the interaction between RXRG (rs2134095) and GC (rs7041) on low-density lipoprotein cholesterol (LDL-c) levels (P=.005). Furthermore, our in silico analysis suggested a functional role for both variants in the regulation of the gene products. Our results suggest that the vitamin D-related genes RXRG and GC affect LDL-c levels. These findings are in agreement with other studies that consistently associate vitamin D and lipid profile. Together, our results corroborate the idea that analyzing gene-gene interaction would be helpful to clarify the genetic component of lipid profile.

Changes of 25-OH-Vitamin D during Overwintering at the German Antarctic Stations Neumayer II and III

Purpose

Humans in Antarctica face different environmental challenges, such as low ultra-violet radiation, which is crucial for vitamin D production in humans. Therefore we assessed changes in 25-OH-vitamin D serum concentration during 13 months of overwintering at the German Stations Neumayer II and III (2007–2012). We hypothesized that (i) 25-OH-vitamin D serum concentration would significantly decrease, (ii) changes would be affected by age, gender, baseline (i.e. pre-overwintering) fat mass, baseline 25-OH-vitamin D serum concentration, and station residence, and (iii) our results would not differ from similar previous studies in comparable high latitudes.

Materials & Methods

25-OH-vitamin D serum concentrations were determined before, after, and monthly during the campaigns from venous blood samples of n = 43 participants (28 men, 15 women). Baseline fat mass was determined via bio impedance analysis and body plethysmography. Data were analyzed for change over time, dependency on independent parameters, and after categorization for sufficiency (>50nmol/l), insufficiency (25-50nmol/l), and deficiency (<25nmol/l). Results were compared with data from similar previous studies.

Results

We found a significant decrease of 25-OH-vitamin D with dependency on month. Age, gender, fat mass, and station residence had no influence. Only baseline 25-OH-vitamin D serum concentrations significantly affected subsequent 25-OH-vitamin D values.

Conclusions

Overwinterings at the Antarctic German research stations Neumayer II and III are associated with a decrease in 25-OH-vitamin D serum concentrations, unaffected by age, gender, baseline fat mass, and station residence. Higher baseline vitamin D serum concentrations might protect from subsequent deficiencies. Residence at the Neumayer Stations may lead to lower vitamin D serum concentrations than found in other comparable high latitudes.

Low serum 25(OH)D levels are assocıated to hıgher BMI and metabolic syndrome parameters in adult subjects in Turkey

BACKGROUND

The aim of this study was to investigate the association of 25(OH)D levels with biochemical, anthropometric, and metabolic data obtained from normal and obese people.

METHODS

This study was carried out on 90 individuals between the ages of 18 to 63 that had various body mass indexes. Blood samples and anthropometric measurements were taken.

RESULTS

Waist circumferences, fat mass, LDL cholesterol levels, HDL cholesterol levels, 25(OH)D levels, and triglyceride levels were significantly different according to the body mass index groups of the participants (p<0.05). When compared to the normal body mass index group, both other groups (overweight and obese) had higher waist circumferences, triglyceride levels, LDL cholesterol levels, fasting insulin levels, HOMA-IR ratios, parathyroid hormone levels, and fat mass, and had lower 25(OH)D levels (p<0.05). The overweight group participants had higher 25(OH)D levels than the obese group, and had lower waist circumferences, fat mass, fasting insulin level, HOMA-IR ratios, and HbA1C and PTH levels than those in the obese group (p<0.05).

CONCLUSION

In conclusion, the mean level of 25(OH)D is very low in overweight and obese individuals and low serum 25(OH)D levels appear to be associated with obesity, visceral obesity, hypertriglyceridemia, insulin resistance, and metabolic syndrome in obese patients.

Higher visceral fat area increases the risk of vitamin D insufficiency and deficiency in Chinese adults

BACKGROUND

Visceral fat area (VFA), a novel sex-specific index for visceral fat obesity (VFO) might play a major role in the development of vitamin D deficiency. However, the association between VFA and vitamin D insufficiency and deficiency in Chinese population is less clear. The aim of this study was to explore the population-level association between VFA and vitamin D insufficiency and deficiency among Chinese men and women.

METHODS

This cross-sectional study involved 1105 adults aged 20-70 years living in Tianjin who were randomly selected and medically examined. All subjects underwent the bioelectrical impedance analysis (BIA) method to estimate the VFA. Serum 25-hydroxyvitamin D3 (25(OH) D3) level was assayed by the high-performance liquid chromatography (HPLC) method and defined insufficiency and deficiency following recommended cutoffs. The association between VFA and vitamin D insufficiency and deficiency was estimated using binary regression analysis.

RESULTS

The total prevalence of vitamin D insufficiency (25(OH) D3: 20-29 μg/L) and deficiency (25(OH) D3 < 20 μg/L) were 26.60 % and 24.89 %, respectively. Significant negative association was observed for VFA with serum 25(OH) D3 levels in men and pre-menopausal women (P < 0.05), not in post-menopausal women (P > 0.05). Moreover, increased VFA was observed to be associated with higher vitamin D insufficiency or deficiency risk with a positive dose-response trend (P for trend < 0.001). As compared to individuals with the lowest VFA, those who had the highest VFA were at 4.9-fold risk of vitamin D insufficiency and deficiency [95 % confidence interval (95 % CI): 1.792-13.365] in men and 1.8-fold risk of vitamin D insufficiency and deficiency (95 % CI: 1.051-3.210) in pre-menopausal women, but not in post-menopausal women [odds ratio (OR) (95 % CI): 2.326(0.903-5.991)].

CONCLUSIONS

These results suggest that higher VFA increases the risk of vitamin D insufficiency and deficiency in men and pre-menopausal women, but not in post-menopausal women. VFA is a better and convenience surrogate marker for visceral adipose measurement and could be used in identifying the risk of vitamin D insufficiency and deficiency in routine health examination.

A therapeutic role for vitamin D on obesity-associated inflammation and weight-loss intervention

Vitamin D plays an essential role in the regulation of skeletal metabolism as well as calcium and phosphate homeostasis, while vitamin D receptor (VDR) regulates de novo lipid synthesis, thereby contributing to the development of obesity. Furthermore, obese individuals are at a greater risk for vitamin D deficiency which may increase the potential risk for chronic inflammation, insulin resistance, and metabolic syndrome. While acute exercise enhances the activation of inflammatory signaling pathways, chronic exercise training may attenuate elevated pro-inflammatory cytokine production, resulting in the improvement of cardiovascular and metabolic health in obese individuals. Supplementation with vitamin D coupled with exercise or mild caloric restriction has been shown to improve markers of fitness and inflammation as well as cholesterol. Therefore, this review primarily addresses the impact of vitamin D deficiency in obesity-related inflammatory imbalances and how exercise and weight-loss interventions may enhance the beneficial effects on vitamin D-mediated inflammation in obesity.

Vitamin D3 supplementation and body composition in persons with obesity and type 2 diabetes in the UAE: A randomized controlled double-blinded clinical trial

BACKGROUND & AIM

The co-existence of vitamin D deficiency with obesity and type 2 diabetes is highly prevalent in the United Arab Emirates. We do not have studies evaluating the vitamin D dose response and sufficiency, and if sufficient substitution dose during a longer period could decrease obesity or change fat distribution in obese type 2 diabetic vitamin D deficient Emiratis.

METHODS

A randomized double-blind clinical trial was conducted for 6 months followed by another 6 months of un-blinded follow up with 87 obese, type 2 diabetic participants. Serum 25-hydroxy vitamin D (S-25(OH)D), anthropometric data, and life-style factors such as diet and sunlight exposure were measured. The study was executed in 3 phases in two arms vitamin D arm (n = 45) and placebo arm (n = 42); in Phase 1 the vitamin D arm received 6000 IU vitamin D3/day (3 months) followed by Phase 2 with 3000 IU vitamin D3/day. During follow up (phase 3) both the arms were un-blinded and supplemented with 2200 IU vitamin D3/day for another 6 months.

RESULTS

At the baseline a significant (p < 0.01) positive association between body fat mass and body weight (r = 0.97) muscle mass (r = 0.47), water mass (r = 0.54), waist circumference (r = 0.82) and serum PTH (r = 0.28) was observed. On supplementation no significant changes in anthropometric dimensions was observed. S-25(OH) D peaked in phase 1 (77.2 ± 30.1 vs 28.5 ± 9.2, p = 0.003) followed by a decrease in phase 2 (62.3 ± 20.8, p = 0.006) paralleled by a decrease in parathyroid hormone in phase 2 (5.9 ± 2.4 vs 4.5 ± 1.8, p < 0.01) compared to baseline in vitamin D group.

CONCLUSION

This study shows no significant influence of vitamin D supplementation on weight, fat mass or waist circumference in type 2 diabetic obese vitamin D deficient participants of Arab ethnicity after one year. Despite a relatively high daily dose of vitamin D3 we did not achieve target levels of S-25(OH)D above 75 nmol/L in this population. However, supplementation was safe, improved s- 25 (OH)D also reducing the incidence of eucalcemic parathyroid hormone elevation.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov Identifier: NCT02101151.

Higher weight in adolescence and young adulthood is associated with an earlier age at multiple sclerosis onset

BACKGROUND

Growing evidence suggests an association between adolescent obesity and increased risk of multiple sclerosis (MS).

OBJECTIVE

The objective of this paper is to investigate whether weight or body mass index (BMI) in adolescence and young adulthood was associated with age at MS symptom onset.

METHODS

Our cohort is comprised of a sub-group of 184 women enrolled in the New York State MS Consortium registry. Individuals were asked to recall their weight at the time of first menstruation and at age 25. BMI was calculated accordingly for age 25. Regression analyses were carried out to investigate the association between weight or BMI and age at onset.

RESULTS

Weight at menarche was significantly related to younger age at symptom onset (β = -0.073, p = 0.001). These results were also found at age 25 for weight (β = -0.080, p < 0.001) and BMI (β = -0.448, p = 0.001). Significantly earlier disease onset (26.9 years ±9.9) was observed in individuals who were overweight at 25 compared to those who were not overweight (32.1 years ±9.2, p = 0.006).

CONCLUSIONS

Women who reported higher weight in adolescence and BMI in early adulthood were younger at MS onset. Future research should investigate whether there is a causal link between body weight and MS, as prevention lifestyle and dietary interventions could be implemented.

Polymorphisms in GC and NADSYN1 Genes are associated with vitamin D status and metabolic profile in Non-diabetic adults

BACKGROUND

Our aim was to assess the associations between vitamin D (vitD) status, metabolic profile and polymorphisms in genes involved in the transport (Group-Component: GC) and the hydroxylation (NAD synthetase 1: NADSYN1) of 25 hydroxyvitamin D (25(OH)D) in non-diabetic individuals.

METHODS

We conducted a cross-sectional study with 323 individuals recruited from the Health Center of Guadeloupe, France. The rs2282679 T > G and rs2298849 T > C in GC and rs12785878 G > T in NADSYN1 were genotyped.

RESULTS

Mean age was 46(range 18-86) years. 57% of participants had vitD insufficiency, 8% had vitD deficiency, 61% were overweight and 58% had dyslipidemia. A higher frequency of overweight was noted in women carrying rs2298849T allele v CC carriers (71% v 50%; P = 0.035). The rs2282679G allele was associated with increased risks of vitD deficiency and vitD insufficiency (OR =3.53, P = 0.008, OR = 2.34, P = 0.02 respectively). The rs2298849 TT genotype was associated with vitD deficiency and overweight (OR =3.4, P = 0.004 and OR = 1.76, P = 0.04 respectively) and the rs12785878 GG genotype with vitD insufficiency and dyslipidemia (OR = 1.80, P = 0.01 and OR = 1.72, P = 0.03 respectively). Based on the number of risk alleles for rs2282679 and rs12785878 combined, a genotype score of 3 (vs. 0-1) was associated with a 5.5 ng/mL average reduction in serum 25(OH)D levels (P = 0.001).

CONCLUSIONS

The GC and NADSYN1 genes are associated with the vitamin D status and might contribute to dyslipidemia and overweight independently of 25(OH)D levels.

Hypovitaminosis D and mild hypocalcaemia are highly prevalent among young Vietnamese children and women and related to low dietary intake

Introduction

In many developing countries including Vietnam, data are lacking on vitamin D and calcium deficiencies whereas those deficiencies can play an important role in the development of bone health and possibly non-communicable diseases. The purpose of this study was to determine the overall prevalence of vitamin D and calcium deficiencies in women and young children and their nutritional related risk factors.

Methods

A cross-sectional study conducted among 595 women of reproductive age and 532 children <5 years from 19 provinces of Vietnam. For each individual, data concerning daily diet, socioeconomic group, anthropometric status were obtained, and plasma concentrations of calcium and vitamin D were measured.

Results

The prevalence of hypovitaminosis D status was very high, with the prevalence of vitamin D deficiency (25(OH)D<30 nmol/L) and insufficiency (25(OH)D between 30–49.9 nmol/L) being 17% and 40% in women and 21% and 37% in children, respectively. Using more liberal cut-off of 75 nmol/L, approximately 90% of the women and children were classified as having hypovitaminosis D. Overweight/obese women had a 2 times lower risk (OR = 0.46, [0.24–0.90]) for vitamin D deficiency than non-overweight and non-obese women. No participant had severe calcium deficiency but moderate and mild hypocalcaemia (plasma calcium concentrations between 1.15-0.9 mmol/L for mild deficiency and between 0.9-0.8 mmol/L for moderate deficiency) affected respectively 14% and 83% of the women with 97% of the children having mild hypocalcaemia. Women and children consumed about 1% of the Institute of Medicine (IOM) recommended nutrient intake (RNI) for vitamin D and less than 43% of the RNI for calcium.

Conclusion

Our study suggests that calcium and vitamin D deficiencies represent a major public health concern in Vietnam. Thus, actions to improve the vitamin D and calcium status of the Vietnamese population should be considered.

Vitamin D intake and dietary sources in a representative sample of Spanish adults

BACKGROUND

Vitamin D plays an essential role in bone mineralisation and its deficiency is associated with several chronic diseases. Some studies have reported a deficient status of vitamin D in Spanish and European population. The present study aimed to assess vitamin D intake, dietary sources of this nutrient and its adequacy with respect to the dietary reference intakes (DRI) in a representative sample of Spanish adults.

METHODS

Four hundred and eighteen adults (aged 18-60 years) from 15 Spanish provinces were studied. They constituted a representative sample of the Spanish adult population. Energy and nutrient intake were determined using a 24-h dietary recall questionnaire for two consecutive days. Vitamin D intake was compared with the DRI for this vitamin.

RESULTS

Mean (SD) vitamin D intake was 3.5 (4.0) μg day(-1) (69.5% of the DRI). Of the participants studied, 81.6% had vitamin D intakes below the DRI and 68.7% had intakes below 67% of the DRI. Of the vitamin D, 91.4% came from food sources and 8.6% came from dietary supplements. The main food sources of vitamin D were fish, eggs, dairy products, cereals, oils and meat. In addition, those subjects who met the DRI for vitamin D had a higher consumption of fish, vegetables and fruits and a lower consumption of meats than those subjects who did not meet the DRI.

CONCLUSIONS

Vitamin D intake was inadequate in the sample of the adult Spanish population. Therefore, an increase in the consumption of oily fish, as well as fortified dairy products and cereals, might help to improve vitamin D intake.

Obesity and burns

The population of overweight patients presenting to burn facilities is expected to increase significantly over the next decades due to the global epidemic of obesity. Excess adiposity mediates alterations to key physiological responses and poses challenges to the optimal management of burns. The purpose of this study is to document the general epidemiological aspects of thermal injuries in the obese population, outline relevant physiological aspects associated with obesity, and draw attention to topics relating to the management, rehabilitation, and prognosis of burns in this emerging subpopulation of patients.

Plasma vitamin D and parathormone are associated with obesity and atherogenic dyslipidemia: a cross-sectional study

Background

Low concentrations of plasma vitamin D (25(OH)D) have been associated with the development of metabolic syndrome (MetS), obesity, diabetes and cardiovascular disease. The objective of this study was to quantify the associations between 25(OH)D and parathormone (PTH) plasma levels and obesity, the presence of MetS, diabetes or atherogenic dyslipidemia (AD) in a large sample of individuals with different degrees of adiposity.

Methods

Retrospective study of all patients who had attended the obesity clinics in a Spanish hospital between 2009 and 2011, and whose concentrations of PTH, 25(OH)D, calcium and alkaline phosphatase had been determined (n=316, 75.9% women). Individuals were categorized by degree of adiposity, presence of MetS, and other comorbidities.

Results

PTH increased but 25(OH)D and calcium decreased with increasing adiposity. The prevalence of 25(OH)D deficiency or insufficiency increased with obesity (<10% when BMI<45kg/m², and 26% when >50). The prevalence of hyperparathyroidism increased from 12% in non-obese to 47.5% in morbidly obese individuals with BMI>50 kg/m². Low plasma 25(OH)D and high PTH concentrations were associated with an increased risk of MetS and AD. These associations disappeared, except in the case of AD for 25(OH)D when adjusting for BMI. Regression analysis revealed that BMI and age or seasonality were independent predictors of PTH and 25(OH)D levels, respectively.

Conclusions

BMI was the variable most strongly associated with plasma 25(OH)D and PTH concentrations in our study. Low 25(OH)D and high PTH concentrations were not independently associated with an increased risk of MetS, or diabetes. Our data support a possible contribution of plasma 25(OH)D to the pathogenesis of hypertriglyceridemia and AD through inflammation.

Decreasing 25-hydroxy-vitamin D levels account for portion of the effect of increasing body mass index on breast cancer mortality

SCOPE

Increased body mass index (BMI) and decreased serum vitamin D are both known to be associated with increased mortality from breast cancer. However, vitamin D levels are lower in obese individuals in general. Recent studies have sought to determine whether serum vitamin D levels can account for some of the association between higher BMI and increased risk for breast cancer and found that low vitamin D levels in the overweight and obese account for up to 40% of the BMI-attributable risk of developing breast cancer.

METHODS AND RESULTS

Here we reviewed the literature to determine if a similar relationship exists between vitamin D, BMI, and breast cancer mortality. Utilizing previously reported independent associations of low vitamin D and high BMI to increases in breast cancer mortality, as well as the known decrement in vitamin D per unit increase in BMI, we estimated that low vitamin D levels may be responsible for roughly 16% of the increased mortality from breast cancer in overweight and obese patients.

CONCLUSION

Although this is a relatively small proportion of the effect of obesity, supplements to increase serum vitamin D levels may represent a way to reduce obesity-associated disparities in breast cancer mortality.

The relationship between serum 25-hydroxy vitamin D concentration and obesity in type 2 diabetic patients and healthy subjects

Background

Both obesity and type 2 diabetes are associated with hypovitaminosis D. The aims of this study were to investigate the association of serum 25-hydroxy vitamin D (25(OH) D) and parathyroid hormone (PTH) concentration with body mass index (BMI) in type 2 diabetic patients compared to control subjects and their predicting role in obesity.

Methods

This cross-sectional study was conducted on 200 subjects (100 type 2 diabetics and 100 healthy controls). Concentration of 25(OH) D, calcium, phosphorous, parathyroid hormone (PTH), fasting blood glucose, HbA₁c, serum insulin, homeostasis model assessment of insulin resistance (HOMA-IR) was determined in the fasting samples. Anthropometric measurements including body mass index (BMI) were also measured.

Results

Eighty-five percent of type 2 diabetics and 79% of healthy subjects were suffering from vitamin D deficiency or insufficiency. Serum concentration of 25(OH) D (22.08 ± 15.20 ng/ml) (r = −0.11, P = 0.04) and calcium (8.94 ± 0.59 mg/dl) (r = −2.25, P = 0.04) has significant statistically with BMI in type 2 diabetic patients. Serum concentration of PTH has non-significantly associated with BMI in diabetic patients and healthy subjects.

Conclusion

Serum levels of vitamin D inversely and PTH positively are associated with BMI after adjusted for age, gender and serum calcium in both type 2 diabetic patients and healthy subjects. These associations were statistically significant for serum concentration of vitamin D and calcium only in diabetic patients. So the status of vitamin D is considered as an important factor in type 2 diabetic patients.

Consumo de micronutrientes e excesso de peso: existe relação?

INTRODUÇÃO: O incremento da obesidade nas últimas décadas se associa às mudanças nos modos de vida da população, incluindo amplas alterações dietéticas, sobretudo na ingestão de micronutrientes. OBJETIVO: Descrever o consumo de micronutrientes e revisar sua implicação no estado nutricional. MÉTODOS: Realizou-se levantamento bibliográfico contemplando artigos nacionais e internacionais, publicados nos últimos 11 anos, nas bases de dados SciELO, LILACS, Medline e sites de organizações governamentais, usando como descritores: "micronutrientes", "consumo alimentar", "excesso de peso" , "saúde" e "estado nutricional" e suas traduções em inglês. RESULTADOS: A deficiência no consumo de micronutrientes é um problema de saúde global, atingindo cerca de 2 bilhões de pessoas, e parece se associar com maior risco de doenças e agravos não transmissíveis, incluindo a obesidade. A insuficiente ingestão de vitamina A favorece o excesso de peso por alteração no metabolismo da tireóide, enquanto a vitamina C se relaciona à síntese de carnitina e oxidação da gordura; e a vitamina D favorece o controle da saciedade e do gasto energético. Quanto aos minerais, o cálcio auxilia a regulação da termogênese e lipogênese/lipólise; e o zinco está envolvido na regulação de insulina e leptina. CONCLUSÃO: A promoção de hábitos alimentares saudáveis por meio de práticas educativas se faz necessária para maior conscientização da população acerca das implicações do consumo de micronutrientes no estado nutricional, devendo compor as estratégias de Saúde Pública de controle da obesidade e suas complicações.

Low 25-hydroxyvitamin D levels and mortality in non-dialysis-dependent CKD

BACKGROUND

Low 25-hydroxyvitamin D (25[OH]D) levels are common in patients with non-dialysis-dependent chronic kidney disease (CKD). The associations between low 25(OH)D levels and mortality in non-dialysis-dependent patients with CKD are unclear.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Patients with stages 3-4 CKD (estimated glomerular filtration rate, 15-59 mL/min/1.73 m(2); n = 12,673) who had 25(OH)D levels measured after the diagnosis of CKD in the Cleveland Clinic Health System.

PREDICTOR

25(OH)D levels categorized into 3 groups: <15, 15-29, and ≥30 ng/mL.

OUTCOMES

We examined factors associated with low 25(OH)D levels and associations between low 25(OH)D levels and all-cause mortality (ascertained using the Social Security Death Index and our electronic medical record) using logistic regression, Cox proportional hazard models, and Kaplan-Meier survival curves.

MEASUREMENTS

25(OH)D was measured using chemiluminescence immunoassay.

RESULTS

Of 12,763 patients with CKD, 15% (n = 1,970) had 25(OH)D levels <15 ng/mL, whereas 45% (n = 5,749) had 25(OH)D levels of 15-29 ng/mL. Male sex, African American race, diabetes, coronary artery disease, and lower estimated glomerular filtration rate were associated significantly with 25(OH)D level <30 ng/mL. A graded increase in risk of 25(OH)D level <30 ng/mL was evident across increasing body mass index levels. Patients who had 25(OH)D levels measured in fall through spring had higher odds for 25(OH)D levels <30 ng/mL. After covariate adjustment, patients with CKD with 25(OH)D levels <15 ng/mL had a 33% increased risk of mortality (95% CI, 1.07-1.65). The group with 25(OH)D levels of 15-29 ng/mL did not show a significantly increased risk of mortality (HR, 1.03; 95% CI, 0.86-1.22) compared with patients with 25(OH)D levels ≥30 ng/mL.

LIMITATIONS

Single-center observational study, lack of data for albuminuria and other markers of bone and mineral disorders, and attrition bias.

CONCLUSIONS

25(OH)D level <15 ng/mL was associated independently with all-cause mortality in non-dialysis-dependent patients with CKD.

Impact of gender on vitamin D deficiency in morbidly obese patients: a cross-sectional study

BACKGROUND/OBJECTIVE

Obesity is associated with vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) <50 nmol/l). We aimed to examine the effect of gender on vitamin D status in severe obesity.

SUBJECTS/METHODS

Cross-sectional study of 2026 morbidly obese patients examined consecutively at a tertiary care centre between November 2005 and June 2010. Serum 25(OH)D concentration and use of vitamin D supplements were registered in all patients. Total vitamin D intake (μg/day) was assessed in a subgroup of 154 patients using a validated food frequency questionnaire.

RESULTS

The male (n=690) and female (n=1336) patients had a mean (s.d.) age of 45.0 (12.1) years and 42.2 (12.2) years (P<0.001), body mass index (BMI) of 44.6 (6.0) kg/m(2) and 44.3 (5.9) kg/m(2) (P=0.30) and waist circumference (WC) of 140 (13) cm and 127 (13) cm (P<0.001), respectively. Male patients had significantly lower mean 25(OH)D concentrations than female patients 50.0 (22.0) nmol/l versus 53.6 (22.4) nmol/l (P=0.001) and a higher rate of vitamin D deficiency (56% versus 47%; P<0.001). Obese men had significantly higher odds of vitamin D deficiency than women (odds ratio=1.41; 95% confidence interval: 1.17-1.70, P<0.001), also after adjustment for season, age, current smoking, intake of vitamin D supplements, BMI and WC (odds ratio=1.39; 95% confidence interval: 1.10-1.76).

CONCLUSIONS

Morbidly obese Norwegian men seeking weight loss treatment have significantly higher odds of vitamin D deficiency than women. Monitoring of 25(OH)D concentrations in obese patients should therefore take gender into account.

Elevated serum 25(OH)D concentrations, vitamin D, and calcium intakes are associated with reduced adipocyte size in women

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.

Serum 25-hydroxyvitamin D is inversely associated with body mass index in cancer

Background

The association between vitamin D deficiency and obesity in healthy populations and different disease states remains unsettled with studies reporting conflicting findings. Moreover, current dietary recommendations for vitamin D do not take into account a person's body mass index (BMI). We investigated the relationship between serum 25-hydroxy-vitamin D [25(OH)D] and BMI in cancer.

Methods

A consecutive case series of 738 cancer patients. Serum 25(OH)D was measured at presentation to the hospital. The cohort was divided into 4 BMI groups (underweight: <18.5, normal weight: 18.5-24.9, overweight: 25-29.9, and obese: >30.0 kg/m²). Mean 25(OH)D was compared across the 4 BMI groups using ANOVA. Linear regression was used to quantify the relationship between BMI and 25(OH)D.

Results

303 were males and 435 females. Mean age at diagnosis was 55.6 years. The mean BMI was 27.9 kg/m² and mean serum 25(OH)D was 21.9 ng/ml. Most common cancers were lung (134), breast (131), colorectal (97), pancreas (86) and prostate (45). Obese patients had significantly lower serum 25(OH)D levels (17.9 ng/ml) as compared to normal weight (24.6 ng/ml) and overweight (22.8 ng/ml) patients; p < 0.001. After adjusting for age, every 1 kg/m² increase in BMI was significantly associated with 0.42 ng/ml decline in serum 25(OH)D levels.

Conclusions

Obese cancer patients (BMI >= 30 kg/m²) had significantly lower levels of serum 25(OH)D as compared to non-obese patients (BMI <30 kg/m²). BMI should be taken into account when assessing a patient's vitamin D status and more aggressive vitamin D supplementation should be considered in obese cancer patients.

First trimester serum 25-hydroxyvitamin D status and factors related to lower levels in gravids living in the Spanish Mediterranean coast

OBJECTIVE

To assess first trimester serum 25-hydroxyvitamin D [25(OH)D] status and factors related to deficient levels in pregnant Spanish women.

METHODS

This cross-sectional study was carried out among 502 gravids (11 to 14 weeks) living in the Spanish Mediterranean sea coast (near Almería at latitude 36° N, longitude 2° W) to whom serum 25(OH)D levels were measured by electrochemiluminescence immunoassay. Logistic and multiple linear regression analysis were performed to assess the influence of ethnicity, immigration status, season of the year at blood sampling, body mass index (BMI), parity and smoking habit over 25(OH)D levels.

RESULTS

The median (interquartile range, IQR) serum 25(OH)D levels for the entire sample was 27.4 ng/mL (IQR = 20.9-32.8). Only 35.9% of participants had adequate serum 25(OH)D levels (≥30 ng/mL) whereas in 41.4% and 22.7% these levels were found to be insufficient (20-29.9 ng/mL) and deficient (<20 ng/mL), respectively. Vitamin D status was found to be significantly lower in Arab women as compared to Caucasian women. 25(OH)D levels were positively correlated with gestational age at sampling and inversely with BMI values (univariate analysis). Logistic regression analysis determined that non-Caucasian ethnicity, season at sampling (autumn/winter), and nulliparity were factors related to deficient 25(OH)D levels. Multiple linear regression found a similar model yet also including maternal weight inversely correlating with 25(OH)D levels.

CONCLUSION

Despite living in one of the sunniest, warmest, and driest climates of Europe, gravids displayed a high prevalence of first trimester insufficient/deficient serum 25(OH)D levels related to season at sampling, nulliparity, maternal weight, and non-Caucasian ethnicity.

Serum 25-hydroxyvitamin D is a predictor of serum 1,25-dihydroxyvitamin D in overweight and obese patients

Recent research suggests that 1,25-dihydroxyvitamin D [1,25(OH)(2)D], a steroid hormone that regulates calcium homeostasis, may also play a role in the development and progression of cancer, multiple sclerosis, cardiovascular, and other diseases. Decreased serum 1,25(OH)(2)D concentrations are often observed in overweight and obese patients. However, little is known about the factors that may influence 1,25(OH)(2)D renal synthesis, because it is generally accepted that serum 1,25(OH)(2)D concentration is strictly regulated by parathyroid hormone and serum concentrations of calcium and phosphorus. In this study, the associations among serum 1,25(OH)(2)D, serum 25-hydroxyvitamin D [25(OH)D], and body composition were analyzed in 1779 patients with excess body weight registered in a Metabolic and Medical Lifestyle Management Clinic in Oslo, Norway. According to our results, serum 25(OH)D, adiposity, age, season of blood sampling, and gender directly influence serum 1,25(OH)(2)D (r = 0.33; P < 0.001), with serum 25(OH)D being the strongest predictor for serum 1,25(OH)(2)D. The 1,25(OH)(2)D concentrations were 25.4 pmol/L (95% Cl: 19.3-31.5; P < 0.001) lower in the lowest 25(OH)D quartile to compared with highest quartile. A seasonal variation was observed for both vitamin D metabolites. Thus, our results suggest that in patients with excess body weight, serum 1,25(OH)(2)D concentrations were associated with 25(OH)D and varied during the year. Therefore, it may also be valuable to measure both serum 25(OH)D and 1,25(OH)(2)D for the evaluation of vitamin D status in overweight and obese persons.

Obesity and increased risk of cancer: does decrease of serum 25-hydroxyvitamin D level with increasing body mass index explain some of the association?

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.

Not a simple fat-soluble vitamin: Changes in serum 25-(OH)D levels are predicted by adiposity and adipocytokines in older adults

OBJECTIVE

To determine the associations between body adiposity and change in serum 25-(OH)D levels over 2.6 years, and if these associations are mediated by metabolic and inflammatory factors in older adults.

METHODS

This is a longitudinal study of 859 randomly selected subjects (mean 62 years, range 51-80, 49% women). Serum 25-hydroxyvitamin D [25-(OH)D] was assessed by radioimmunoassay at baseline and 2.6 years later. Baseline serum level of leptin was assessed by radioimmunoassay and interleukin (IL)-6 by a chemiluminescent immunoassay in the first 183 subjects.

RESULTS

In multivariable analyses, body mass index, trunk fat percentage and waist-to-hip ratio were significant predictors of increased incident vitamin D deficiency [a 25-(OH)D < 50 nmol L⁻¹ at follow-up when ≥50 nmol L⁻¹ at baseline] and decreased recovery of vitamin D deficiency [a 25-(OH)D ≥ 50 nmol L⁻¹ at follow-up when < 50 nmol L⁻¹ at baseline]. Change in 25-(OH)D levels per annum was also independently predicted by baseline leptin (β: -0.09/unit, 95% CI: -0.17, -0.03), IL-6 (β: -0.68/quartile, 95% CI: -1.35, -0.02) and total cholesterol/high-density lipoprotein (HDL) ratio (β: -0.51, 95% CI: -0.88, -0.14). The associations between body adiposity measures and change in 25-(OH)D completely disappeared after adjustment for leptin, diminished after adjustment for IL-6, but remained unchanged after adjustment for total cholesterol/HDL ratio. All associations were independent of season and sun exposure.

CONCLUSIONS

Body fat is not simply a passive reservoir for 25-(OH)D. In addition to season and sun exposure, 25-(OH)D levels appear to be determined by metabolic and, to a lesser extent, inflammatory factors, and these appear to mediate the effects of adiposity on change in 25-(OH)D.