The effects of vitamin D supplementation on the antioxidant serum level in 6-13 years old children with ADHD

Background: The causes of Attention-deficit/hyperactivity disorder (ADHD) (the most common psychological disorder is still unknown. The main symptoms include impulsivity, hyperactivity and attention deficit. Some studies have shown the relationship between ADHD and oxidative stress, and yet some researches have shown the effects on vitamin D on the antioxidants level. This research intends to identify the effect of vitamin D supplementation on the antioxidant serum level in 6-13 years old children with ADHD. Methods: This double blind clinical trial was conducted in Isfahan city, the center of Iran, from October 2015 to February 2016. The sample included 35 subjects of both groups that were randomly selected among 6-13 years old children with ADHD diagnosed by pediatric psychologist. The intervention group consumed 1000 IU of vitamin D3 daily for three months, and the control group used placebo for the same period of time. Their stature and weight were recorded by digital instruments without the shoes with the least clothes. The next step was to train the food record of the students to the parents so that 3 food records were taken during the study. 25-hydroxyvitamin D3 (25(OH)D3), TAC (Total antioxidant capacity), MDA (Malondialdehyde), CAT (Catalase) and GSH (Glutathione) of the participants of both groups were measured before and after the intervention. Results: In this Study, both groups were adjusted in terms of their age, gender and BMI. The mean score of the variables of leisure time and sport showed no significant difference in the both groups. Comparing the average TAC and MDA between the two groups before intervention didn’t show a significant difference (P1TAC=0.06) (P1MDA=0.32), but after the intervention, the vitamin D intake group showed the increase in TAC and decrease in MDA (P2TAC=0.001) (P2 MDA=0.01). Moreover, CAT and GSH showed no significant difference in the two groups before and after intervention. Conclusion: Vitamin D supplementation for 3 months led to the improvement of antioxidant capacity by the increase of TAC and decrease of MDA, but the CAT and GSH showed no significant change in the mentioned period of time.