OBJECTIVE:

Psychological disorders are highly prevalent worldwide. The present study aimed to investigate the relationship between major dietary patterns and prevalence of psychological disorders in a large sample of Iranian adults.

DESIGN:

A cross-sectional study was done to identify dietary patterns derived from factor analysis. Dietary data were collected through the use of a validated dish-based semi-quantitative FFQ. Psychological health was examined by use of the Hospital Anxiety and Depression Scale and the General Health Questionnaire.

SETTING:

The study was conducted in Isfahan, Iran, within the framework of the Study on Epidemiology of Psychological, Alimentary Health and Nutrition (SEPAHAN).

SUBJECTS:

Iranian adults (n 3846) aged 20-55 years.

RESULTS:

After adjustment for potential confounders, greater adherence to the lacto-vegetarian dietary pattern was protectively associated with depression in women (OR=0·65; 95 % CI 0·46, 0·91). Normal-weight participants in the top quintile of this dietary pattern tended to have decreased odds of anxiety compared with those in the bottom quintile (OR=0·61; 95 % CI 0·38, 1·00). In addition, the traditional dietary pattern was associated with increased odds of depression (OR=1·42; 95 % CI 1·01, 1·99) and anxiety (OR=1·56; 95 % CI 1·00, 2·42) in women. Normal-weight participants in the highest quintile of the traditional dietary pattern had greater odds for anxiety (OR=1·89; 95 % CI 1·12, 3·08) compared with those in the lowest quintile. The Western dietary pattern was associated with increased odds of depression in men (OR=1·73; 95 % CI 1·07, 2·81) and anxiety in normal-weight participants (OR=2·05; 95 % CI 1·22, 3·46). There was a significant increasing trend in the odds of psychological distress across increasing quintiles of the fast food dietary pattern in women (P-trend=0·02).

CONCLUSIONS:

Recommendation to increase the intake of fruits, citrus fruits, vegetables, tomato and low-fat dairy products and to reduce the intakes of snacks, high-fat dairy products, chocolate, carbonated drinks, sweets and desserts might be associated with lower chance of psychological disorders.