Vegans and vegetarians who consume packaged and processed meat alternatives are more likely to suffer from depression, according to a new study.
Researchers at Bond University in Queensland have found that a poor-quality plant-based diet, compared to a diet high in fresh produce, can lead to deterioration in mental health.
Nutritional psychiatry researcher Megan Lee said the discovery was particularly significant given the growing popularity of vegan and vegetarian lifestyles and the proliferation of packaged foods aimed at these groups.
Processed foods are high in refined vegetable oils, grains, salt, and sugar.
âThere is a general perception that following a plant-based diet is inherently healthy, but like any diet, it depends on what you put in your mouth,â Lee said.
âVegans and vegetarians don’t automatically eat heaps of fruits and vegetables, because there are all of these fully processed and fully refined products.
“People can inadvertently consume high levels of processed plant foods, which is a known risk factor for increased depression.”
During the study, researchers examined the diet and mental health of 219 vegans and vegetarians aged 18 to 44 across the country, who were then asked to complete relevant questionnaires.
Researchers found that those who had plenty of fresh fruits, vegetables, nuts, seeds, legumes, and whole grains in their diet had a lower risk of depression than those who ate low-quality diets.
Not a cure
The link between diet and risk of depression was likely due to the presence of complex carbohydrates, fiber, probiotics and antioxidants, all of which have been shown to reduce symptoms of depression, Lee said.
“He seems to have more of a protective role,” she said.
“Our research did not find that a plant-based diet was a treatment or a solution for those who were already depressed.”
Vegans and vegetarians are already more vulnerable to depression than the general population, added Lee.
“We think this (susceptibility to depression) could be because vegans and vegetarians tend to be more aware of external issues – animal welfare, environmental concerns – and they can be socially ostracized due to their choice of diet, âshe said.
Research has also found that meat eaters can also protect their mental health by consuming more fruits and vegetables.
Across Australia, more than 2.5 million people have chosen to go without meat.