Plasma concentrations of selected antioxidants in autistic children and adolescents

Few studies have demonstrated an increased vulnerability to oxidative stress in autism. The results of previous studies have shown that endogenous antioxidant defence is insufficient, indicating that exogenous antioxidant could play a crucial role for oxidative stress prevention in autism. Plasma concentrations of vitamins C, E, A, carotenoids beta-carotene and lycopene were measured in 51 subjects with autistic spectrum disorders aged 5-18 years (27 children aged 5-10 years, 24 subjects aged 11-18 years). Older autistic group was compared with a group of healthy Slovak subjects aged 11-18 years. Older autistic subjects vs. healthy control showed significantly higher vitamin C and beta-carotene plasma values with 92% and 71% vs 54% and 13% of optimal over-threshold values, respectively. This indicates a reduced risk of free radical disease. In younger vs. older autistic group the similarly high plasma vitamin concentrations were recorded. Favourable values of these vitamins suggested that consumption of fruit and vegetables in autistic subjects is optimal. Autistic average vitamin E and A plasma concentrations (non-significantly changed in comparison to control group) were below-threshold with low percentage of over-threshold values. Insufficient vitamin E and A plasma values indicate lower consumption of food rich in vitamins A and E (e.g. whole-grain products, plant oils, oil seeds, nuts, fat spreads and dairy products). Autistic average lycopene concentration is lower in comparison to published non-Slovak data. Conclusions of this pilot study suggest that plasma concentrations of exogenous antioxidants, vitamins E and A, and lycopene in autistic subjects are insufficient (Tab. 1, Ref. 30). Full Text (Free, PDF) www.bmj.sk.