Vitamin D status and its association with adiposity and oxidative stress in schoolchildren.

The aim of this study was to evaluate serum 25-hydroxyvitamin D [25(OH)D] level and its association with adiposity, inflammation, and oxidative stress in schoolchildren. A total of 1488 schoolchildren ages 7 to 11 y were recruited in Harbin, China (latitude: 44°04'N-46°40'N) in May. Serum 25(OH)D, which is an indicator of vitamin D status, was determined. Anthropometric data were collected following general physical examinations. Serum lipids, glucose metabolism indices, inflammatory molecules, and oxidative stress markers were determined. Dietary intake and physical activity also were assessed. The median serum 25(OH)D concentration was 18.4 ng/mL. Of the 1488 schoolchildren included, 839 (56.4%) had vitamin D deficiency [25(OH)D < 20 ng/mL]. Children in the vitamin D deficiency group had significantly higher body weight (34.1 ± 3.8 versus 31.5 ± 3.3 kg; P < 0.001), body mass index (18.4 ± 2.2 versus 16.8 ± 1.7 kg/m(2); P < 0.001), waist circumference (60.1 ± 8.5 versus 57.2 ± 7.7 cm; P < 0.001), percentage of body fat (20.2% ± 2.6% versus 19.1% ± 2.4%; P < 0.001), and significantly lower concentrations of serum superoxide dismutase (95.38 ± 12.22 versus 127.62 ± 15.98 U/mL; P < 0.001) compared with those in the vitamin D sufficiency group. After adjusting for sex, age, body mass index, and percentage of body fat, a positive association between serum 25(OH)D and superoxide dismutase was found (β = 0.230; P < 0.001). Vitamin D deficiency is common in Harbin schoolchildren. Serum 25(OH)D is closely associated with adiposity and superoxide dismutase in schoolchildren, suggesting that vitamin D deficiency potentially increases the risk for diseases caused by higher adiposity and oxidative stress.

Zhang HQ ，Teng JH ，Li Y ，Li XX ，He YH ，He X ，Sun CH ... -  《-》

Vitamin D status is a determinant of skeletal muscle mass in obesity according to body fat percentage.

Vitamin D deficiency is now being recognized as an emerging problem worldwide. Obesity has been found to be associated with lower serum 25-hydroxyvitamin D [25(OH)D] concentrations due to various mechanisms. There is increasing evidence showing the extraskeletal health benefit of vitamin D. Previous studies demonstrated the relationship between vitamin D and adiposity. However, the association between vitamin D status and skeletal muscle mass has not been established in healthy obese individuals in tropical countries. The aim of this cross-sectional study was to assess vitamin D status and its relationship to serum 25(OH)D concentrations and body composition, including skeletal muscle mass (SMM) and adiposity in healthy obese individuals without diabetes who live in Thailand, which is located near the equator. We enrolled 163 obese Thai individuals (59.5% women) from the obesity clinic at the Ramathibodi Hospital, Mahidol University, in Bangkok, Thailand. The prevalence of vitamin D deficiency (<20 ng/mL) and vitamin D inadequacy (<30 ng/mL) were 49 (30.1%) and 148 (90.8%), respectively. In all, 98% of the individuals with body mass index >35 kg/m(2) had vitamin D inadequacy. Serum 25(OH)D concentrations were negatively associated with percent body fat (%BF) (r = -0.23; P = 0.003). Moreover, vitamin D status was positively associated with SMM (r = 0.18; P = 0.03) and the association remained after controlling for body fat mass and age (P = 0.003). Interestingly, in the individuals with lowest tertile of %BF, multiple linear regression analysis revealed that the significant positive predictors of %SMM were vitamin D status and male sex; the negative predictor was the body mass index after adjusting for age and exercise duration. Our study demonstrated the high prevalence of vitamin D deficiency in obese, Thai populations without diabetes. Vitamin D status was an independent predictor of %SMM of patients with lowest tertile of %BF. We speculated that adiposity might play a role in the relationship of vitamin D and SMM.

Shantavasinkul PC ，Phanachet P ，Puchaiwattananon O ，Chailurkit LO ，Lepananon T ，Chanprasertyotin S ，Ongphiphadhanakul B ，Warodomwichit D ... -  《-》

Association of vitamin D concentrations with adiposity indices among preadolescent children in Korea.

Lee HA ，Kim YJ ，Lee H ，Gwak HS ，Park EA ，Cho SJ ，Oh SY ，Ha EH ，Kim HS ，Park H ... -  《-》

Vitamin D deficiency and anthropometric indicators of adiposity in school-age children: a prospective study.

Gilbert-Diamond D ，Baylin A ，Mora-Plazas M ，Marin C ，Arsenault JE ，Hughes MD ，Willett WC ，Villamor E ... -  《-》

Low serum 25-hydroxyvitamin D concentrations are associated with total adiposity of children in the United States: National Health and Examination Survey 2005 to 2006.

A negative association between serum 25-hydroxyvitamn D (25[OH]D) concentrations and adiposity has been found in adults. We hypothesized that serum 25(OH)D concentrations of children would correlate positively with vitamin D intake and correlate negatively with adiposity measures. Using a nationally representative sample of children aged 6 to 18 years from the National Health and Nutrition Examination Survey 2005-2006 (n = 2492), serum 25(OH)D concentrations were compared with measures of adiposity (weight, waist circumference [WC], WC-to-height ratio, body mass index, skinfold thickness, and percent body fat). Based on Endocrine Society's serum 25(OH)D concentration criteria, 26.9% ± 2.3% of the children were vitamin D deficient (<20 ng/mL) and 26.5% ± 2.6% had sufficient levels (≥30 ng/mL). Controlling for age, sex, ethnicity, and income, linear regression analysis indicated that dietary vitamin D intake was positively associated with serum 25(OH)D levels (P < .05) and markers of adiposity were negatively associated with serum 25(OH)D levels: WC, WC-to-height ratio, body mass index, and triceps skinfold thickness (P < .05). A subgroup analysis (n = 2086; 8-18 years) of body fat, fat mass index, and percent body fat measured by dual-energy x-ray absorptiometry also was negatively associated with serum 25(OH)D levels (P < .05). When standardized β coefficients were compared, strength of the inverse relationship to serum 25(OH)D concentrations was very similar for several adiposity measures. In conclusion, risk of a vitamin D deficiency was fairly common among children based on Endocrine Society criteria and low serum 25(OH)D concentrations were strongly associated with increased adiposity in children.

Moore CE ，Liu Y 《-》