Empirically derived food-based dietary inflammatory index is associated with increased risk of psychological disorders in women.

There is no study on the association of empirically derived food-based dietary inflammatory index (FDII) and risk of psychological disorders. We investigated the association between FDII and odds of psychological disorders in Iranian adults. In this cross-sectional study, data on dietary intakes of 3363 Iranian adult participants were collected using a validated dish-based 106-item semi-quantitative food frequency questionnaire. FDII score was constructed based on participants' dietary intakes of 28 pre-defined food groups. The Iranian validated version of Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ) was used to assess psychological disorders. Depression, anxiety and psychological distress were defined based on standard criteria. After controlling for potential confounders, participants in the top quintile of FDII score had a greater odds of depression (OR: 1.49; 95% CI: 1.08-2.06), anxiety (OR: 1.92; 95% CI: 1.24-2.96), and psychological distress (OR: 1.55; 95% CI: 1.10-2.19) compared with those in the bottom quintile. When we did the analyses stratified by gender, we found a significant positive association between FDII score and depression (OR: 1.57; 95% CI: 1.04-2.35), anxiety (OR: 1.99; 95% CI: 1.19-3.34), and psychological distress (OR: 1.68; 95% CI: 1.10-2.56) among women comparing the highest and the lowest quintiles. We found no significant association between FDII score and psychological disorders in men. We found that greater FDII score was positively associated with psychological disorders. In the gender-stratified analysis, this was seen in women but not in men.