The concept of
food addiction refers to addiction-like behaviours that develop in association with the intake of highly palatable foods. Previous research indicates that a high proportion of individuals with
Major Depressive Disorder (MDD) meet the criteria for
food addiction, and are also at an increased risk of
weight gain and
chronic disease. In the central nervous system,
dopamine is a
neurotransmitter associated with reward salience and food intake, whereas peripheral
dopamine is involved in sympathetic stress regulation, digestion and gastrointestinal motility. However, little research has examined relationships between peripheral
dopamine, depressive symptoms and problematic eating behaviours in MDD. Biometrics, psychopathology and plasma
dopamine levels were compared between participants with MDD (n = 80) and controls (n = 60). Participants were sub-categorised into those meeting or not meeting Yale
Food Addiction Scale (YFAS) criteria. Psychometric measures of mood and appetite were used to assess MDD symptoms, problematic eating behaviours and
food-addiction related symptoms. Twenty-three (23; 29%) MDD participants met the Yale criteria for
food addiction. Depressed individuals meeting YFAS criteria had significantly greater psychopathology scores for both mood and eating compared to depressed individuals not meeting YFAS criteria and controls. A significant interaction between
food addiction status and sex was also observed for plasma
dopamine levels. Plasma
dopamine levels correlated positively with disordered eating behaviours in females, and negatively in males. The results provide evidence that depressogenic excess eating and
weight gain are associated with peripheral
dopamine levels. Longitudinal research is warranted investigating endocrine dysregulation and excess eating in MDD, which may inform interventions and reduce
chronic disease risk in affected individuals.