Eating behaviour and depression before and after antidepressant treatment: a prospective, naturalistic study.

Eating behaviour of severely depressed patients was assessed before (n = 56), after acute (n = 46) and during maintenance (n = 35) treatment and compared to matched normal controls in order to investigate the behavioural mechanisms underlying the weight gain induced by antidepressants. Assessments included food intake, appetite and food preferences. Before treatment, there was a decrease in appetite and in food intake with a relative excess of carbohydrates and a preference for sweets. Maintenance treatment was associated with substantial weight gain. All differences in eating behaviour between patients and controls disappeared, with the exception of a decrease in appetite in a subgroup of less-improved patients. These results suggest that antidepressant treatment induces weight gain by mechanisms that are largely independent of their action on mood.