A Mediterranean-Style Diet Improves Major Depression in Adults.

This is such an exciting study that proves that sometimes, the most simple things (such as a healthy diet – go figure!) makes the biggest difference for our health!

What I love most is that the diet is high in fat!  Yes, up to 40% of the daily energy intake is from fat!  Healthy fat, that is, consisting of fish, olive oil and nuts.  I have spoken of the importance of having adequate healthy fats in the diet many times (see this post), and it’s something I recommend to all my patients, especially those with anxiety and depression.

The ways in which depressive illness may be influenced by a healthy diet, are likely to be related to a number of biological pathways that have roles in inflammation, oxidative stress, brain plasticity and the gut microbiotia. In addition, changes in behavioural patterns such as cooking, shopping, meal patterns, planning etc, may also have a positive, therapeutic effect.

Mediterranan diet

Read on to find out more about the study.

Study Details

In this Australian, 12 week, parallel-group, single blind randomised, controlled trial, aptly named the ‘SMILES’ trial (Supporting the Modification of lifestyle In Lowered Emotional States), 67 patients with moderate to severe depression were enrolled to investigate the effects of diet, compared to those receiving social support.

 Dietary Intervention

Picture source: shape.com

Picture source: shape.com


The focus of the diet was the consumption of the following key food groups with recommended servings as follows:

  •          Whole grains – 5-8 serves/day
  •          Vegetables – 6 serves per day
  •          Fruit - 3 serves/day
  •          Legumes – 3-4 serves/week
  •          Low fat, unsweetened dairy – 2-3 serves/day
  •          Raw, unsalted nuts – 1 serve/day
  •          Fish – at least 2 serves/week
  •          Lean red meat – 3-4erves/week
  •          Chicken – 2-3 serves/week
  •          Eggs – up to 6 /week
  •          Olive oil – 3 tablespoons/day

Participants also had to reduce the intake of ‘extras’ and have these no more than 3 times/week:

·         Sweets, refines carbohydrates/cereals, fried food, fast food, processed meat and sugary drinks.

·         Alcohol intake above 2 standard drink/day was considered an ‘extra’ and participants were encouraged to choose red wine to be consumed only with a meal.

Interestingly, the diet macronutrient composition consisted primarily of FAT! Here’s the breakdown of the diet:

·         40% FAT

·         18% PROTEIN

·         37% CARBOHYDRATES

·         2% ALCOHOL

·         3% FIBRE AND OTHERS


After 12 weeks of treatment, the dietary support group had significantly greater improvement between baseline and 12 week scores on the MADRS (the Montgomery–Åsberg Depression Rating Scale) compared to the social support group.

In addition, remission was achieved for 32.3% of people in the treatment group!

It was concluded that dietary improvements may be and effective and accessible treatment strategy for the management of these highly prevalent mental disorders.  

Take Home Message

I guess at the end of the day, it’s really not rocket science.  We all just need to remember that what goes in our mouth, has HUGE effect on not only on our physical body, but also our emotional and mental well being.

For many of my patients, I recommend a diet with similar principles, largely focused on consuming an abundance of healthy fats (avocado, nuts, fish, olive oil, flaxseeds), vegetables and fruit; good sources of protein (eggs, turkey, fish, some red meat); and in most cases, sources of whole grains such as brown rice, rolled oats, quinoa and buckwheat.

It is important to also remember that diets aren’t always one-size-fits-all and should be tailored further to support individual needs.  For example, in practice I find that dairy doesn’t sit well with a lot of people and so I speak to them about their options and alternatives. For those who do eat dairy, I recommend full fat, not low fat!  Similarly, I particularly find that gluten can also be detrimental for those suffering with depression (and auto-immune conditions) and for those, we would adjust the diet accordingly.  .

Furthermore, in recommending a Mediterranean diet,  I actually stress the importance of vegetables, protein and fats, and would encourage these over grains for most people - particularly if they are carrying extra weight.  Basically, you almost cannot have too many vegetables, but you can certainly have too many carbs and grains.

Healthy shopping list