Improving a young person’s diet might be the key to helping them overcome their depressive symptoms, according to new Australian research.
In a randomised controlled trial of just over 100 people with elevated levels of depression symptoms and a regular diet that was assessed as poor, researchers found that those allocated to the ‘diet change’ group, on average improved to the point of having no clinically significant symptoms after just three weeks. This was in stark contrast to the ‘habitual diet control group’ who unsurprisingly, showed no improvement in symptoms over the duration of the study.
Despite the impressive result, the diet change intervention was not all that intensive – it simply involved instructions from a registered dietician via a 13-minute video. And the advice was fairly basic – increase intake of fruit and vegetables, wholegrain cereals, protein, fish, nuts and seeds, unsweetened dairy, olive oil and spices and decrease intake of refined carbohydrate, sugar, fatty or processed meats and soft-drinks. Pretty standard stuff.
Diet compliance was measured via self-reported questionnaires and spectrophotometry, which led to another important finding from the study.
“One of the most interesting findings is the fact that diet change was feasible in the population,” the researchers from Macquarie University in Sydney said.
“We anticipated that the symptoms of depression, including low energy, reduced motivation and apathy would present barriers to eating well,” they said. But the reality was the diet group managed to both increase their intake of the recommended foods and avoid the foods designated as unhealthy.
“This study therefore contributes to a body of research suggesting that despite many perceived barriers, nutritional intake can be modified in youth with mental health issues,” the study authors said in the PLOS One.
To be eligible to participate in the study, people had to be aged between 17 and 35 years and score seven or more on the Depression, Anxiety and Stress Scale-21 Depression scale (DASS-21-D). If they were receiving treatment – pharmacotherapy and/or psychological therapy -they had to have been receiving it for at least two weeks before the trial started. Also participants had to have a poor diet as assessed by the Dietary Fat and Sugar Screener questionnaire.
There is strong evidence that people with depression typically have unhealthy dietary habits. But less well-known is whether this is the cause or the effect. What this randomised controlled trial shows is that, at the very least, improving diet can be a useful adjunctive treatment for managing depression.
Furthermore, at follow-up conducted three months after the initial study, researchers found the improvements in depression scores among those in the diet change group were sustained. In fact the scores did not differ significantly from scores at the completion of the original study.
And in addition to the psychological benefits, the dietary changes will help these patients’ physical health.
“The current intervention involved such a small degree of face-to-face contact and very little cost or risk, thus there are few downsides to adopting this approach to improving mood,” they concluded. A win-win by any measure.
Francis HM, Stevenson RJ, Chambers JR, Gupta D, Newey B, Lim CK. A brief diet intervention can reduce symptoms of depression in young adults – A randomised controlled trial. PLoS One. 2019 Oct 9; 14(10): e0222768. DOI: 10.1371/journal.pone.0222768