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Adult Mental Health: The Role of Nutrition - WATCH HERE

Food and exercise can treat depression as well as a psychologist

Adrienne O'Neil and Sophie Mahoney

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A 'diet and lifestyle' therapy was as effective as psychotherapy for reducing depression, according to a new clinical trial in which both interventions were delivered 'virtually'. And it would cost less to provide.

FAB RESEARCH COMMENT:

For adults with clinical-level depression, an intervention to improve the nutritional quality of their diets and encourage regular exercise, was as effective as psychotherapy in reducing depressive symptoms, a new clinical trial has found. 


The dietary intervention involved providing information and guidance on how to reduce consumption of ultra-processed foods high in sugar, salt, artificial additives and unhealthy fats, and to follow instead a 'Mediterranean-type' diet based on whole or minimally processed foods.

(NB - while heavily 'plant-based' - any traditional Mediterrean diet includes not only plenty of vegetables & fruits, nuts & seeds and whole grains but also fish and seafood - the main food source of the long-chain omega-3 needed for brain health - along with eggs, and small amounts of meat and dairy products).  

The study took place during the COVID epidemic, so both programmes were delivered virtually, each involving up to six online group sessions over eight weeks, facilitated by health professionals.

Previous randomised controlled trials have already shown that dietary interventions can significantly improve symptoms of depression - and that they are both feasible and acceptable to patients. See:


This new trial supports and extends these existing findings.

The importance of this mounting evidence that clinical-level depression can be alleviated by simple, low-cost changes in diet and lifestyle is hard to understate, given

(1) the high prevalence and huge costs of this condition not only to those affected, but to wider society, and
(2) the fact that at least 30% of patients with depression are not helped by the best standand pharmaceutical or cognitive-behavioural treatments (even where these are available and acceptable to them).

Furthermore, the dietary and psychological interventions did not differ in either their efficacy or total costs to service providers.

However, as the authors point out in their article below, the diet and lifestyle programme was slightly cheaper to deliver; and compared with psychologists, dietitians (or other suitably qualified professionals) can also be trained more quickly, and at a lower cost.

These findings indicate that diet and lifestyle interventions could offer a cost-effective addition to existing treatment options for the management of depression.

Large-scale replication studies are now clearly warranted.

To find out more about this subject, please see this FAB webinar - in which a leading UK expert in Nutritional Psychiatry, with almost 20 years of NHS experience in mental health services, gives a state-of-the-art update on:

Adult Mental Health - The Role of Nutrition:

What the public, policymakers and professionals need to know


For more information, FAB comments and links to other news articles and studies on this important topic, see also:


And for more information on clinical trials of dietary interventions for depression - and to stay updated - please see and bookmark the following link - where new articles will be added as these are forthcoming:

2nd August 2024 - The Conversation

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Around 3.2 million Australians live with depression.

At the same time, few Australians meet recommended dietary or physical activity guidelines. What has one got to do with the other?

Our world-first trial, published this week, shows improving diet and doing more physical activity can be as effective as therapy with a psychologist for treating low-grade depression.

Previous studies (including our own) have found “lifestyle” therapies are effective for depression. But they have never been directly compared with psychological therapies – until now.

Amid a nation-wide shortage of mental health professionals, our research points to a potential solution. As we found lifestyle counselling was as effective as psychological therapy, our findings suggest dietitians and exercise physiologists may one day play a role in managing depression.

What did our study measure?

During the prolonged COVID lockdowns, Victorians’ distress levels were high and widespread. Face-to-face mental health services were limited.

Our trial targeted people living in Victoria with elevated distress, meaning at least mild depression but not necessarily a diagnosed mental disorder. Typical symptoms included feeling down, hopeless, irritable or tearful.

We partnered with our local mental health service to recruit 182 adults and provided group-based sessions on Zoom. All participants took part in up to six sessions over eight weeks, facilitated by health professionals.

Half were randomly assigned to participate in a program co-facilitated by an accredited practising dietitian and an exercise physiologist. That group – called the lifestyle program – developed nutrition and movement goals:

  • eating a wide variety of foods
  • choosing high-fibre plant foods
  • including high quality fats
  • limiting discretionary foods, such as those high in saturated fats and added sugars
  • doing enjoyable physical activity.

The second group took part in psychotherapy sessions convened by two psychologists. The psychotherapy program used cognitive behavioural therapy (CBT), the gold standard for treating depression in groups and when delivered remotely.

In both groups, participants could continue existing treatments (such as taking antidepressant medication). We gave both groups workbooks and hampers. The lifestyle group received a food hamper, while the psychotherapy group received items such as a colouring book, stress ball and head massager.

Lifestyle therapies just as effective

We found similar results in each program.

At the trial’s beginning we gave each participant a score based on their self-reported mental health. We measured them again at the end of the program.

Over eight weeks, those scores showed symptoms of depression reduced for participants in the lifestyle program (42%) and the psychotherapy program (37%). That difference was not statistically or clinically meaningful so we could conclude both treatments were as good as each other.

There were some differences between groups. People in the lifestyle program improved their diet, while those in the psychotherapy program felt they had increased their social support – meaning how connected they felt to other people – compared to at the start of the treatment.

Participants in both programs increased their physical activity. While this was expected for those in the lifestyle program, it was less expected for those in the psychotherapy program. It may be because they knew they were enrolled in a research study about lifestyle and subconsciously changed their activity patterns, or it could be a positive by-product of doing psychotherapy.

There was also not much difference in cost. The lifestyle program was slightly cheaper to deliver: A$482 per participant, versus $503 for psychotherapy. That’s because hourly rates differ between dietitians and exercise physiologists, and psychologists.

What does this mean for mental health workforce shortages?

Demand for mental health services is increasing in Australia, while at the same time the workforce faces worsening nation-wide shortages.

Psychologists, who provide about half of all mental health services, can have long wait times. Our results suggest that, with the appropriate training and guidelines, allied health professionals who specialise in diet and exercise could help address this gap.

Lifestyle therapies can be combined with psychology sessions for multi-disciplinary care. But diet and exercise therapies could prove particularly effective for those on waitlists to see a psychologists, who may be receiving no other professional support while they wait.

Many dietitians and exercise physiologists already have advanced skills and expertise in motivating behaviour change. Most accredited practising dietitians are trained in managing eating disorders or gastrointestinal conditions, which commonly overlap with depression.

There is also a cost argument. It is overall cheaper to train a dietitian ($153,039) than a psychologist ($189,063) – and it takes less time.

Potential barriers

Australians with chronic conditions (such as diabetes) can access subsidised dietitian and exercise physiologist appointments under various Medicare treatment plans. Those with eating disorders can also access subsidised dietitian appointments. But mental health care plans for people with depression do not support subsidised sessions with dietitians or exercise physiologists, despite peak bodies urging them to do so.

Increased training, upskilling and Medicare subsidies would be needed to support dietitians and exercise physiologists to be involved in treating mental health issues.

Our training and clinical guidelines are intended to help clinicians practising lifestyle-based mental health care within their scope of practice (activities a health care provider can undertake).

Future directions

Our trial took place during COVID lockdowns and examined people with at least mild symptoms of depression who did not necessarily have a mental disorder. We are seeking to replicate these findings and are now running a study open to Australians with mental health conditions such as major depression or bipolar disorder.