Traditional Brazilian diet and extra virgin olive oil reduce symptoms of anxiety and depression in individuals with severe obesity: Randomized clinical trial

Abstract

Rational & objective: Although the relationship between obesity, anxiety and depression is known, the clinical benefits of nutrition therapy in individuals with obesity have been scarcely studied. This study assessed the effectiveness of a traditional Brazilian diet (DieTBra) and extra virgin olive oil (EVOO) on the symptoms of anxiety and depression in severe obese participants.

Method: This was a parallel randomized clinical trial in adults with severe obesity (Body Mass Index - BMI ≥ 35 kg/m²), DietBra Trial. Participants were randomized into three intervention groups in a ratio of 1: 1: 1 and followed up for 12 weeks. The three intervention groups were: 1) DieTBra, 2) 52 mL/day EVOO, and 3) DieTBra +52 mL/day EVOO. The symptoms of anxiety and depression were assessed by the Hospital Anxiety and Depression Scale. The outcome variables were: anxiety, depression and simultaneous anxiety and depression in the same individual.

Results: 149 severe obese individuals were randomized. The mean BMI was 46.3 ± 6.5 kg/m² with a mean age of 38.9 ± 8.7 years. After randomization, individuals on medication for depression and anxiety were excluded, totaling 129 at baseline, with 44:43:42 per group. At the end of 12 weeks 113 individuals completed the study. There was a significant reduction of symptoms for the three groups: EVOO, DieTBra and DieTBra + EVOO, respectively: anxiety 38.23% (p = 0.019), 45.83% (p=<0.014), 33.33% (p < 0.013) depression 55.17% (p=<0.001), 50.00% (p=<0.007), 34.61% (p=<0.035), and anxiety/depression 57.69% (p=<0.001), 66.67% (p=<0.014), 27.78% (p=<0.013).

Conclusions: Both DieTBra and olive oil interventions were effective in reducing symptoms of anxiety and depression in severe obese adults. These interventions can be integrated with clinical protocols for treatment of symptoms of anxiety and depression in severe obese individuals.

Trial registration: Clinicaltrials.gov NCT02463435.

Keywords: Anxiety; Depressive symptoms; Diet therapy; Olive oil; Severe obesity.