A new study from scientists at the Japan Institute for Health Security has found that a popular Japanese diet – full of vegetables, fermented foods, beans and fish – may protect against symptoms of depression.
Researchers studied 12,5000 working adults and found those who followed the washoku diet, consisting of fish, vegetables, rice and soybeans, were less likely to report low mood, anxiety and stress than those who ate processed foods, sugar, meat, and refined grains.
According to the study, those who followed a modern version of the diet, which adds raw vegetables and fruit while cutting back on sodium, saw an even bigger benefit, where risk was reduced by 20 per cent.
The findings remained consistent when considering factors including age, gender, and job stress levels. However, the benefits were less notable among those working very long hours.
Scores were developed for traditional Japanese diet items: white rice, miso soup, soy products, cooked vegetables, mushrooms, seaweed, fish, salty foods and green tea.
Meanwhile, the modified diet had vastly improved scores when it came to salty foods. It also exchanged white rice for a minimally processed variety, as well as adding fruits, raw vegetables and dairy products into the mix.
Vegetables contain folate, which is known to help produce serotonin and dopamine – neurotransmitters that play a vital role in regulating mood. Meanwhile, green tea, miso and colourful vegetables contain antioxidants which can help reduce oxidative stress to the brain.
Although further research is needed to establish a causal link between the washoku diet and the prevention of depression, scientists said the result of the study was “very encouraging”.
“Our findings contribute to the growing body of evidence suggesting the important role of culturally specific diets in mental health,” researchers who published their findings in the journal Psychiatry and Clinical Neurosciences said.
“The present study informs both clinicians and public health professionals about a possible link between the Japanese diet and mood disorders. If confirmed, the findings may provide a basis for using the dietary pattern approach as a public health strategy for the prevention of depression.”
Back in 2018, research suggested the Mediterranean diet – made up of fruits, vegetables, legumes, nuts and fish – could help ward off depression.
People who more closely followed the classic Mediterranean diet were found to be around 33 per cent less likely to develop depression compared to those who had a stereotypically Western diet of meat, processed foods, saturated fat and sugar.
