Dietary Phytochemical Index and Psychological Disorders in a large sample of Iranian adults: a population-based study

Abstract Background: Intake of plant foods including of Phytochemicals may be decrease risk of mental health. Aim: This study aim to investigate association of Dietary Phytochemical Index)DPI( with symptoms of depression, anxiety and stress in a large sample of Iranian adults. Methods: In this cross-sectional study, a total of 7385 adult aged 20-50 years old were provided from the recruitment phase of Yazd Health Study, a population-based cohort research on Iranian adults. Food intakes were assessed via validated and reliable food frequency questionnaire. Symptoms of depression, anxiety and stress were assessed using a validated Depression, Anxiety and Stress Scales questionnaires with 21-items. DPI was calculated by percent of daily energy intake taken from phytochemical-rich foods. Results: After adjusting for potential confounders, normal weight subjects in the highest tertile of DPI had a lower risk of depression (OR: 0.65; 95% CI: 0.44–0.97) and anxiety symptoms (OR: 0.65; 95% CI: 0.45–0.93) compared with those in the lowest tertile. However, no apparent association was found between depression, anxiety and stress in overweight and obese subjects. Conclusion: We found significant association between DPI and mental health in normal weight adults. Prospective studies are required to approve these conclusions.