If you’re feeling a bit off, do you reach for comfort foods like ice-cream or chocolate, simply to make you feel ‘happier’?
As a far healthier alternative, a new study suggests that Japan’s traditional washoku diet, which is rich in fish, soy and vegetables, could help to fend off depression

The Japanese diet is often associated with longevity and good health, but research suggests it may also help prevent depression. Studies into Japan’s traditional washoku diet — rich in fish, vegetables, minimally processed rice and soybeans — found that those consuming it were 17 to 20 per cent less likely to experience depression than those who ate it less often. The diet also contains miso soup, mushrooms, seaweed and green tea.
As the study was observational, it doesn’t establish a direct causal link. However, it does support other findings that suggest a strong link between nutrition and mental health.
Here’s why a Japanese diet may boost your mood …
It’s full of oily fish

One element of the Japanese diet that’s particularly beneficial for our mental health is the high consumption of oily fish, as mentioned in this latest study. Oily fish contains omega-3 fatty acids, specifically EPA [eicosapentaenoic acid] and DHA [docosahexaenoic acid], which are very beneficial for brain health and associated with improved mood and mental wellbeing. Good sources include salmon, trout, mackerel, herring and sardines.
Several studies have shown that increasing your intake of omega-3 is also linked to improved cognitive function, such as sharper focus and memory, and can help reduce your risk of dementia and Alzheimer’s.
… and colourful vegetables
The washoku diet contains a wide range of vegetables that are cooked, fermented or raw, including leafy greens like spinach and kale, root vegetables such as sweet potato, radish and carrot, and salad. And seaweed which is packed with brain-friendly micronutrients like iodine, magnesium and zinc.

A diet high in antioxidants from vegetables helps reduce inflammation in the brain. This is really important for reducing the risk of depression because inflammation is the causal pathway. Another reason we’re beginning to believe vegetables are good for mental health is because they nourish your gut microbiome, with the gut-brain axis playing an important role in maintaining good mental health. When people start increasing their plant and fibre intake, their mood improves. Plants also provide bioactive compounds that reduce inflammation and contribute to better metabolic health. factor for mental health.
Japanese food is often fermented

Japanese vegetables are often fermented, which means they’ve undergone a preserving process that boosts their nutritional value and leaves them richer in probiotics, which are live microbes that improve gut health. Fermented foods may improve the gut microbiome and gut-brain axis. Good options include fermented yoghurt, kefir and sauerkraut.
The diet is rich in antioxidants

As well as plants, the diet also contains green tea and soy products, such as miso soup that’s made from soybeans. Soy contains isoflavones and phytoestrogens, which have been shown to reduce depressive symptoms, and folate, a B vitamin that supports the nervous system. These all contain good levels of antioxidants, which can reduce oxidative stress to the brain, There’s even the possibility that umami, a key flavour characteristic of Japanese food, stimulates the parasympathetic nervous system in the brain, which contributes to mental stability.
It keeps you full

It’s high in fibre, contains a diverse range of plants, is low in high-risk processed foods and processed meat, with a high focus on fish, vegetables and fermented foods, which is known for keeping us full. This in turn reduces our risk of overeating, obesity, and being overweight, all of which increase the risk of poor mental health. A 2021 study from Exeter University found that our risk of depression rises with body weight.
This study adds to the growing body of evidence that a healthy, balanced diet rich in whole, minimally processed foods, low in sugar and salt, and high in antioxidants, fibre and healthy fats supports our mental health,