Objective: A low antioxidants status has been shown to result in oxidative stress and cognitive impairment. Because antioxidants can protect the nervous system, it is expected that a better blood antioxidant status might be related to sustained attention. However, the relationship between the blood antioxidant status and visual and auditory sustained attention has not been investigated. The aim of this study was to evaluate the association of fruits and vegetables intake and the blood antioxidant status with visual and auditory sustained attention in women.
Method: This cross-sectional study was performed on 400 healthy women (20-50 years) who attended the sports clubs of Tehran Municipality. Sustained attention was evaluated based on the Integrated Visual and Auditory Continuous Performance Test using the Integrated Visual and Auditory (IVA) software. The 24-hour food recall questionnaire was used for estimating fruits and vegetables intake. Serum total antioxidant capacity (TAC), and erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in 90 participants.
Results: After adjusting for energy intake, age, body mass index (BMI), years of education and physical activity, higher reported fruits, and vegetables intake was associated with better visual and auditory sustained attention (P < 0.001). A high intake of some subgroups of fruits and vegetables (i.e. berries, cruciferous vegetables, green leafy vegetables, and other vegetables) was also associated with better sustained attention (P < 0.02). Serum TAC, and erythrocyte SOD and GPx activities increased with the increase in the tertiles of visual and auditory sustained attention after adjusting for age, years of education, physical activity, energy, BMI, and caffeine intake (P < 0.05).
Discussion: Improved visual and auditory sustained attention is associated with a better blood antioxidant status. Therefore, improvement of the antioxidant status through an appropriate dietary intake can possibly enhance sustained attention.
Keywords: Visual and auditory sustained attention; antioxidant status; fruits; vegetables.