Relationship between 25-Hydroxy Vitamin-D and Obesity in 2-7 years old Children Referred to a Paediatric Hospital in Iran

Is vitamin D deficiency influenced by obesity during the first 5 years of life? A cross-sectional multicenter study

Evidence on the association of 25-hydroxyvitamin D (25[OH]D) and obesity during the first 5 years of life is limited in China. The objective of this study was to examine the associations between weight, weight for age z score (ZWAZ), weight for length/height z score (ZWHZ), and body mass index for age z score (ZBMI) and 25(OH)D. This was a large population-based cross-sectional multicenter study in which the children aged 0-5 years were recruited from 12 children's healthcare centers by a stratified cluster random-sampling method in 10 cities of the Jiangsu province, China. The 25(OH)D concentration was determined by ELISA. A total of 5289 children were investigated. For 0-71 months children with obesity and nonobesity, the prevalence of vitamin D deficiency was 36.0% and 29.8%, and the 25(OH)D level was 59.8 and 64.0 nmol/L, respectively, and there were all significant difference. Compared with children with nonobesity, children with obesity had higher risk of vitamin D deficiency (OR [95% CI]: 1.33 [1.02, 1.72], p < .05), and had lower 25(OH)D level (β = -3.84, 95% CI = -7.58, -0.09, p < .05). The results for children aged 24-71 months were similar to those for children aged 0-71 months. However, no significant difference was observed in children aged 0-23 months. Vitamin D deficiency was observed in children with greater adiposity during the first 5 years of life. However, the results mainly came from those in the age group of 2 to 5 years instead of the first 2 years in their lives.

Vitamin D and Zinc are Interlinked but Affected by Different Growth Factors in Iranian Children and Adolescents: Vitamin D and Zinc in Iranian Children and Adolescents

Background: Zinc and vitamin D are essential factors required for growth. Recently, studies have shown a possible link between serum zinc and vitamin D levels. Objectives: This study was designed to evaluate this link and its possible affecting growth factors in children and adolescents in Iran. Methods: This cross-sectional study was performed on the data obtained from children aged 2 to 18 years old referring to a growth assessment clinic for routine growth follow-ups in the city of Shiraz from April to August 2019. A total of 454 children who were checked for 25-hydroxyvitamin D and zinc simultaneously were included. Results: Vitamin D was negatively correlated with body mass index (BMI) z-scores, while zinc was positively correlated with vitamin D and height z-scores. Subjects with vitamin D levels ≤ 8.6 ng/mL were 2.081 times more likely to have a zinc deficiency. Vitamin D insufficiency was significantly higher in overweight and obese children. Mean vitamin D and zinc levels were significantly lower, and vitamin D insufficiency was significantly higher in boys than girls. While mean zinc levels were significantly lower in short children, the prevalence of zinc deficiency was not statistically different between short and normal height statures. Conclusions: Very low vitamin D levels are likely to be accompanied by zinc deficiency, possibly caused by malnutrition and the modulatory effect of serum vitamin D on zinc absorption. Unlike zinc deficiency, vitamin D insufficiency is much more prevalent in Iranian children than in children from other countries. Vitamin D and zinc are associated with BMI and height z-scores, respectively.

Association between serum 25-hydroxyvitamin D concentrations and obesity in one-year-old Chinese infants

Recent studies suggested that vitamin D is linked with obesity, but evidence in infants is scarce. Therefore, we aimed to make an exploration in infants. A total of 414 infants at one year old who visited Maternity and Child Health Care Hospital of Wuxi in China were recruited. Finger-stick blood sampling was conducted in all the subjects, and serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured. Maternal characteristics during pregnancy and infantile information were collected by questionnaires or extracting from medical records. Multivariable linear models were performed to assess the relationship between 25(OH)D and body mass index (BMI), while multivariable logistic regression models were used to examine the association between 25(OH)D and obesity. Among the 414 infants, 69 (16.67%) and 81 (19.57%) infants were defined as obesity and vitamin D deficiency [25(OH)D < 50 nmol/L], respectively. The mean (SD) of 25(OH)D concentration was 68.05 (19.05) in infants without obesity, which was significantly higher than that of obese infants [60.36(18.49), p = .002]. Inverse linear relationships were observed between 25(OH)D level and BMI (β = -0.017, p = .004) as well as BMI Z-score (β = -0.010, p = .004). Furthermore, vitamin D deficiency was associated with an increased risk of obesity of infants (adjusted odds ratio = 2.74, 95% confidence interval = 1.20-6.25, with 25(OH)D ≥ 75 nmol/L as a reference). The results showed that serum 25(OH)D concentrations were significantly lower in infants with obesity, suggesting vitamin D deficiency may be an independent risk factor for obesity among one-year-old Chinese infants.

Is There Any Relationship between Vitamin D Deficiency and Gross Motor Development in 12-Month-Old Children?

OBJECTIVE

We aimed to assess the possible relationship between vitamin D deficiency and gross motor developmental milestones in Iranian children in Tehran City, Iran.

MATERIALS & METHODS

In this cross-sectional study, 186 healthy children of one-yr-old age referring to a children hospital in Tehran, Iran from May 2015 to April 2016, were enrolled. The gross motor developmental milestone of children and their serum vitamin D concentration were evaluated.

RESULTS

Overall, 186 children, 92 males (49.5%) were studied. Twenty-four patients (12.9%) just were able to sit without support, and 40 patients (21.5%) to stand alone and to sit without support. Besides, 122 patients (65.6%) were able to walk with assistant or alone and to sit without support and stand alone. Vitamin D was sufficient in 148 children (79.6%), insufficient in 32 (17.2%) and deficient in 6 (3.2%). Sufficient vitamin D was significantly correlated with walking ability (P<0.001, OR=3.9, 95%CI=1.9-8.4).

CONCLUSION

Considering the significant correlation between vitamin D deficiency and gross motor developmental milestones in this population of children, children referring to gross motor developmental delay need to be thoroughly evaluated for vitamin D deficiency.