Prevalence of Obesity and Overweight among School-Aged Children in Saudi Arabia and Its Association with Vitamin D Status.

BACKGROUND: Childhood obesity is a significant global public health problem. Worldwide data showed an increasing trend over the years. We aimed to explore the prevalence of obesity, and its association with vitamin D status. METHODS: This cross-sectional study was conducted during the period from 2016 to 2017. The study included 3613 schoolchildren aged 6-19 years in the western, central, and eastern regions in Saudi Arabia. Anthropometric data including age, sex and body mass index (BMI) was collected and the serum 25OH- vitamin D (25OHD) was measured. Age-sex standardized BMI Z-scores using the 2007 World Health Organization growth standards were applied. RESULTS: Data from 3613 school-aged children (females = 51.8%), with equal percentage of participants from each region were analyzed. Prevalence of obesity and overweight was estimated at 7.1% and 14.4% respectively. An increasing trend was detected with age (p: 0.006). Obesity started to increase at the age of 10 years and continued to increase until 19 years. Most of the obese children (64.2%) had deficient vitamin D levels, compared to 33.7% of them with suboptimal levels and only 2.0% with optimal levels (p: <0.001). CONCLUSIONS: This large cohort study revealed a high prevalence (21.5%) of obesity and overweight in school children aged between 6-19 years with increasing trend with age.  Children with high BMI showed extremely high prevalence of VDD and VDI. These findings are alarming and point to the need for effective national interventions that include improving and encouraging access to physical activity and exposure to sunlight, educational activities for students, parents, and schoolteachers and possible enrichment of staple food with vitamin D.

Prevalence of Vitamin D Deficiency and Calcium Homeostasis in Saudi Children.

OBJECTIVE: Vitamin D deficiency (VDD) and vitamin D insufficiency (VDI) are significant health problems all over the world. The aim of this study was to determine the prevalence of VDD and VDI in children and adolescents residing in 8 provinces in the Kingdom of Saudi Arabia and to also investigate calcium homeostasis in these subjects. METHODS: A cross-sectional study was conducted in 2110 participants aged between 6 and 15 years. Information on socio-demographic status, anthropometric measurements, knowledge about vitamin D, color of the skin, dietary intake, sun exposure experience, smoking, and physical activity were collected through a questionnaire given to the parents of all subjects. The subjects were divided into three groups as vitamin D deficient, vitamin D insufficient, and vitamin sufficient according to their blood level of vitamin D [VDD ≤25 nmol/L (25 hydroxy vitamin D), VDI >25-50 nmol/L, and VDS >50 nmol/L]. RESULTS: VDD was highly prevalent in this group of children. 95.3 of the subjects had either VDD (45.5%) or VDI (49.9%). The prevalence rate of VDD combined with VDI was higher in females (97.8%) compared to males (92.8%) (p<0.001). Only 1.6% had significant hypocalcaemia. Children with dark skin had lower concentrations of vitamin D and higher concentrations of parathormone. A positive correlation was observed between 25 hydroxy vitamin D level and serum calcium, inorganic phosphate, and alkaline phosphatase concentrations. onclusion: The results showed a high prevalence of VDD and VDI in Saudi children with significantly higher prevalence in girls. These findings necessitate the set-up of a national program for vitamin D supplementation and health education for this vulnerable group.