A study published in BMC Med conducted a randomized controlled experiment to test the causal relationship between a healthful diet and depression. We currently have studies that show an association between what we eat and our mood. However, establishing a causal relationship makes the case for dietary changes as part of treating depression.
The results of this trial suggest that improving one’s diet according to current recommendations targeting depression may be a useful and accessible strategy for addressing depression in both the general population and in clinical settings.
Jacka, Felice et al. | A Randomised Controlled Trial of Dietary Improvement for Adults with Major Depression (the ‘SMILES’ trial).
The Study
The 12-week study tested the effect of dietary intervention in treating moderate to severe depression. Researchers divided participants into two groups.
The test group received seven nutritional consulting by a clinical dietician. The recommended diet focused on 12 key food groups including, whole grains, vegetables, fruits, and legumes, while reducing refined, processed, fried, and sugary foods. Participants were not advised to limit food intake, since the study did not focus on weight-loss.
The control group, on the other hand, received social support sessions, with similar length and schedule as the dietary group. These sessions consisted of “befriending” protocols NOT psychotherapy sessions.
Participants filled out depression rating questionnaires before and after.
The Results
At 12 weeks, 32% of those in the dietary group and 8% in the social support groups achieved remission from depression. Calculating costs of the diet, researchers found that a healthful and wholesome diet costs less. Moreover, “improvements in depressive symptoms were independent of weight change.” Meaning, food can heal us without resulting in weight-loss.
Why Does Food Affect our Mental Health?
The study doesn’t answer this question, but learning about gut health and the vagus nerve, allows us to better understand the why questions.
The Takeaway
We get depressed for a variety of reasons. And part of the beauty of wellness journeys is the element of customization. Studies like these make a strong case for the medical community to adopt a more holistic approach to depression. In the future, nutritionists might play a larger role in treating mental issues.
This study and my experience show that eating fresh food is actually less expensive that highly processed ones. But the fact is that eating a wholesome diet will require more home cooking and more of your time. This is why it’s important to have strategies such as meal-prepping and making cooking enjoyable and a part of household activity.
