Author : Kalliopi Kasvis
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (922 download)
Book Synopsis Changes in Vitamin D Status of Overweight and Obese 6 to 12- Year Old Children by : Kalliopi Kasvis
Download or read book Changes in Vitamin D Status of Overweight and Obese 6 to 12- Year Old Children written by Kalliopi Kasvis and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Background: Vitamin D status is lower in Canadian children who are overweight or obese compared to children of healthy weights. Objective: The objectives of this study are 1) to determine the vitamin D status of overweight and obese children, 2) to examine the association between changes in fat mass (FM) and vitamin D status, and 3) to determine if there is a relationship between regional adiposity and blood concentrations of 25-hydroxyvitamin D (25(OH)D).Methods: Data was collected at baseline, and then every 3 months for a one year period, from participants enrolled in the McGill Youth and Lifestyle Intervention with Food and Exercise (MYLIFE) study (NCT01290016); healthy children aged 6-12 y with body mass index (BMI)-for-age >85th percentile were included. Chemiluminescence immunoassay was used to measure plasma 25(OH)D. Standard measurements of weight, height and waist circumference (WC) were taken at each visit; BMI and BMI z-scores were calculated (WHO AnthroPlus, Geneva, Switzerland, 2009). Body composition was measured using dual-energy X-ray absorptiometry to determine whole body and regional adiposity. Z-scores for adiposity indicators were calculated based on reference data from the National Health and Nutrition Examination Survey; children were then separated into tertiles based on these z-scores. Constitutive and facultative skin pigmentation was measured using a hand-held spectrophotometer in order to determine Fitzpatrick skin types. Children were categorized according to cutaneous UVB synthesis period. Ethnicity was self-disclosed and pubertal status was reported at baseline and categorized according to Tanner stages. Differences in 25(OH)D among tertiles of each adiposity indicator (eg: % body fat (%BF), FM, WC) were tested using a mixed model ANOVA. Logistic regression was used to determine the odds ratio of not meeting recommended 25(OH)D cutoffs. Results: Data from 101 children (46 boys and 55 girls) were used in this study. The mean 25(OH)D concentration at baseline was 59.8 ± 1.3 nmol/L, with no significant difference between sexes (p=0.740). Boys had lower %BF (p=0.012), greater BMI z-scores (p=0.001) and greater WC (p=0.013) than girls. After one year, those who decreased FM appeared to have better plasma 25(OH)D than those who maintained or gained FM (59.2 vs. 55.3 nmol/L; p=0.310), although significance was not reached. Every kg increase in FM was associated to increased odds of not reaching plasma 25(OH)D cutoffs of 75 nmol/L (OR: 1.2, 95% CI: 1.1-1.4, p=0.006). Arm fat (OR: 2.6, 95% CI: 1.3-5.2, p=0.009) was associated to greater odds of missing the cutoff than leg fat (OR: 1.6, 95% CI: 1.1-2.3, p=0.009). Android:gynoid fat patterning was not significant (p=0.066). Conclusion: Adiposity in overweight and obese children, irrespective of location, has an inverse relationship with vitamin D status. Therefore, adiposity likely needs to be considered when establishing dietary intake recommendations to match population cutoffs for vitamin D status. Future large-scale longitudinal research is required to examine if a reduction in FM would lead to a significant increase in vitamin D status." --
