according to New studyVegetarians have about twice as many episodes of depression as meat eaters.
The study published in Journal of Affective Disorders, on survey data from Brazil. chime with previous search that found higher rates of depression among those who did not eat meat. However, the new study indicates that this association exists independently of dietary intake.
According to a Gallup poll, about 5% of the US population considers themselves vegetarian. Women are 50% more likely to be vegetarian than men. People who consider themselves liberal are more likely to be vegetarian than conservative or moderate.
It may seem easy to look at the association between diet and certain health problems and to suppose that the former is caused by the latter by some form of nutritional deficiency.
However, the new analysis took into account a wide range of nutritional factors, including total calorie intake, protein intake, micronutrient intake, and level of food processing. This suggests that the higher rates of depression among vegetarians are not caused by the nutritional content of their diet.
So what might explain the link between vegetarianism and depression? Is there a non-food mechanism that makes the first cause the second? Or is the relationship going back to something else entirely?
First, it is possible that depression increases the likelihood that people will become vegetarians rather than the other way around. The Symptoms of depression It can include rumination of negative thoughts, as well as feelings of guilt.
Assuming that depressed and non-depressed people are equally likely to experience the unpleasant reality of massacres and factory farming, it is possible that depressed people are more likely to reflect on those thoughts, and more likely to feel guilt for their role in creating demand.
A depressed vegetarian, in this case, isn’t necessarily wrong to think this way. While depression is sometimes described as having unrealistic negative perceptions, There is suggestive evidence People with mild to moderate depression have more realistic judgments about the outcome of uncertain events and more realistic perceptions of their roles and abilities.
In this case, there really is cruel treatment of animals in meat production. This is actually caused by consumers’ demand for cheap meat.
Second, it is possible that sticking to a vegan diet can lead to depression for reasons other than nutrition. Even if there is no “happy food ingredient” that is lacking in a vegetarian diet, it may be because leaving meat is causing depression through other means.
For example, a vegetarian diet may affect one’s relationship with others and participation in social activities. In fact, it is sometimes associated with Harassment or other forms of social ostracism.
Notably, the new study is based on survey data collected in Brazil She is famous for her meat-rich diet. Some survey data indicated a A sharp increase in the vegetarian system in Brazil in recent yearsfrom 8% in 2012 to 16% in 2018. However, the latest paper surveyed more than 14,000 Brazilians and found only 82 vegetarians – barely more than half a percent.
One must wonder if the same link between vegetarianism and depression can be observed in India or in other countries where vegetarianism is considered more than a social norm. Most importantly, that file The rate of vegetarians in the UK is increasing And other developed countries, will we see the relationship disappear over time?
Finally, it is possible that neither the plant nor the other causes depression, but both are related to a third factor. This could be a number of characteristics or experiences associated with vegetarianism and depression.
for example, Women are more likely than men to be vegetariansAnd the It is also more likely to suffer from depression. However, the Brazilian study took gender into account, and excluded this third variable.
One variable that has not been examined, but is reasonably linked to vegetarianism and depression, is exposure to violent images of the meat industry. Prevention of cruelty to animals is The most common reason Vegetarians give to avoid meat.
Documentaries like Dominion And the Earthlings depicting cruelty in the meat industry cannot easily be described as satisfying films. One can easily imagine that a person who consumes this type of media will become a vegetarian, especially when most people choose to look the other way, depressed.
There are several possible reasons for the association between vegetarianism and depression. This new study suggests that plant-based nutrition is not the cause of depression.
Alternatively, a vegetarian social experience may contribute to depression, depression may make you more likely to become a vegetarian, or both vegans and depression may be caused by a third variable, such as exposure to images of violent meat industry.
Written by Chris Bryant, Research Associate Emeritus, Department of Psychology, University of Bath.
This article was first published in Conversation.