Vitamin D Deficiency and Insufficiency in Obese Children and Adolescents and Its Relationship with Insulin Resistance

Abstract

Objectives. We aimed to determine the relationship between insulin resistance and serum 25-hydroxyvitamin D (25-OHD) levels in obese children and their nonobese peers. Materials and Methods. Included in the study group were 188 obese children (aged 9–15 years), and 68 age- and gender-matched healthy children of normal weight as control group. Anthropomorphic data were collected on patients and fasting serum glucose, insulin, serum lipids, alanine aminotransaminase (ALT) and 25-OHD were measured. The homeostatic model assessment of insulin resistance (HOMA-IR) was calculated in both groups. Results. The levels of 25-OHD in the obese group were significantly lower than those of the nonobese (P = 0.002). HOMA-IR, triglycerides, low-density lipoprotein, and ALT levels in the obese group were significantly higher than values of control group (P < 0.001 and P = 0.002, resp.). In the obese group, vitamin D deficiency, insufficiency, and sufficiency (25-OHD < 10 ng/dl, < 20, >10 ng/dl; > 20 ng/dl, resp.) were not correlated with HOMA-IR (r : −0.008, P = 0.935). HOMA-IR was negatively correlated with BMI, BMI SDS, and BMI%, and triglycerides, low-density lipoprotein, and ALT levels (P < 0.001). Conclusion. The insulin resistance of the obese subjects who were vitamin D deficient and insufficient did not statistically differ from those with vitamin D sufficiency. Low 25-hydroxyvitamin D levels were not related with higher insulin resistance in obese children and adolescents. In obese subjects, insulin resistance was affected more from BMI, BMI SDS, and BMI% than from 25-hydroxyvitamin D levels.

Vitamin D deficiency in obesity and its relationship to insulin resistance and plasma leptin levels – preliminary study

“…Moreover, in obese subjects there was a significant trend towards higher insulin concentrations and HOMA-IR in those individuals with lower 25(OH)D concentration. Conversely, Torun et al (26) found that insulin resistance of the obese subjects, who were vitamin D deficient and insufficient did not differ from those with vitamin D sufficiency.…”

Prevalence of vitamin D insufficiency in children with forearm fractures

“…10,13 An increased incidence of vitamin D deficiency and/or insufficiency was investigated in girls, obese children and children with darker skin pigmentation. [14][15][16] Adequate intake levels for vitamin D from food and/or milk are met by less than half of children in lower socioeconomic regions. 17,18 Also, infants born in such populations have low vitamin D stores and may receive little additional vitamin D if they are breastfed without supplements.…”

Consumo alimentar e síndrome metabólica em adolescentes

“…Essa relação pode ser justificada pelo depósito de 25 (OH) D nos adipócitos, diminuindo sua biodisponibilidade e desencadeando uma cascata de reações hormonais que resultam em aumento da fome e diminuição do gasto energético [42]. Em adolescentes obesos, baixas concentrações de vitamina D também têm sido associadas com níveis reduzidos de HDL-c [43] e elevados de triglicerídeos e do índice homeostatic model assessment para resistência à insulina (HOMA-IR) [44]. Um estudo realizado com 3.577 adolescentes americanos com idades entre 12 e 19 anos encontrou maior chance de hipertensão arterial e SM para os indivíduos no menor quartil do nível sérico de 25 (OH) D, em comparação com o maior quartil, independentemente da adiposidade corporal [45].…”