There is much suggestion that diet quality plays an important role in mood and is a possible risk or protective factor for depression. Specifically, research has suggested diets higher in plant foods such as vegetables, fruits, legumes and wholegrains and lean proteins including fish are associated with reduce risk for depression.
I am a huge advocate for promoting the important role diet quality plays in having a healthy mood and new research in this area excites me! A recent study looked at the efficacy of a modified Mediterranean diet program for the treatment of major depression. Over 12 weeks, participants with major depression who had poor diet quality, defined as, low fibre, protein, fruit and vegetable intake and high intake of sweets, processed meats and salty snacks were put into 1 of 2 groups. Group 1 received dietary support and group 2 received social support.
The focus of the dietary support group was to increase dietary quality by encouraging the consumption of the following key food groups:
- whole grains (5–8 servings per day)
- vegetables (6 per day)
- fruit (3 per day)
- legumes (3–4 per week)
- low-fat and unsweetened dairy foods (2–3 per day)
- raw and unsalted nuts (1 per day)
- fish (at least 2 per week)
- lean red meats (3–4 per week)
- chicken (2–3 per week)
- eggs (up to 6 per week)
- olive oil (3 tablespoons per day)
While trying to increase the above food groups, study participants were asked to limit sweets, refined cereals, sugary drinks, processed meats, fried food and fast food, alcohol other than red and white wine. Wine was allowed if not more than 2 standards drinks’ per day.
At the end of 12 weeks, the diet group had significantly changed their diet by increasing consumption of wholegrains, fruit, dairy, olive oil, pulses and fish, while reducing junk foods.
Results of the study showed a significant reduction in depression symptoms amongst the diet group. The authors noted that that dietary changes may have had an impact on inflammation, oxidative stress, brain plasticity as well as gut microbiotia, all suggested to play a role in depression. Importantly also, it was suggested behavioural changes associated with food such as cooking, shopping and having meal structure/patterns may have also had a therapeutic benefit.
While the research is preliminary, it adds to the current body of evidence supporting the beneficial effects of a healthy diet on mood!
If you are interested in improving your diet quality, here is a Mediterranean shopping list to get you started:
- Brown rice, quinoa, freekeh, farro, oats, wholemeal/buckwheat pasta, wholegrain bread
- Raw walnuts, almonds, macadamia nuts, sunflower seeds, pumpkins seeds
- Tomatoes, berries, leafy greens, capsicum, onion, figs, pears, cabbage, cauliflower, broccoli, green beans, carrot and sweet potato
- Fresh basil, coriander, parsley, oregano
- Dried spices – chilli, cinnamon, cumin, sumac
- Lentils, chickpeas, cannellini beans, red kidney beans, green peas
- Salmon, sardines, tuna, mackerel, whiting, prawns, squid
- Extra virgin olive oil
- Greek yoghurt, ricotta cheese, feta cheese
- Small quantity of lean lamb, beef, veal, chicken and turkey
- Prioritise planning! Flip through cookbooks or magazines and jot down some meals for the week, have a simple plan in place
- Purchase good quality produce, head to the markets and talk to farmers, smell and touch food before buying
- Keep food simple, dress salads and vegetables with olive oil and flavour dishes with fresh herbs and spices
- Snack on fruit and vegetables
- Cook more often and share your food with loved ones!
- Swap refined carbohydrates for wholegrains (see list above)
- Aim to eat ½ plate vegetable at each main meal
Jacka, F et al 2016, ‘A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial),’ BMC Medicine, Vol. 15, No. 1, pp. 23