Dietary intake of persons with depressive and psychotic disorders in Singapore

Nutritional psychiatry is an emerging field of study that investigates the role of diet and nutrition in mental health. Studies conducted in the general population have linked depressive symptoms with poor dietary patterns. The aim of this study was to characterise the dietary intake and analyse the dietary pattern using the Dietary Approach to Stop Hypertension (DASH) in a sample of psychiatric patients in a multiethnic Asian nation.

Participants were recruited from an outpatient clinic and an inpatient unit at the Institute of Mental Health in Singapore. Self-reported dietary habits of a sample of psychiatric patients (N=380) were analysed using DASH. To examine the variables associated with DASH scores, a linear regression was conducted with the full sample and sociodemographic variables.

Persons with depressive disorders had a mean DASH score of 21.3 (±4.2), while persons with psychotic disorders had a mean DASH score of 21.2 (±4.9). Respondents who were older (B=1.94, 95% confidence interval [CI] 0.91-2.96, P<0.001), female (B=1.09, 95% CI 0.07-2.11, P=0.04) and economically inactive (B=1.98, 95% CI 0.006-3.96, P=0.049) were more likely to report a higher diet quality compared with their respective counterparts, while smokers (B= -1.39, 95% CI -2.45 to -0.34, P=0.009) tended to report a lower diet quality compared with their non-smoking counterparts.

Dietary patterns of persons with mental disorders were characterised. A host of sociodemographic factors, and not diagnosis of mental disorders, influenced the dietary quality of people with depressive and psychotic disorders. Clinicians treating psychiatric patients need to be aware of the nuanced reasons behind poor dietary choices and provide targeted psychoeducation to specific subgroups within the patient population.