ARE VEGETARIAN MORE DEPRESSED ?
KEY POINTS
1) A meta-analysis on depression in vegetarians and non-vegetarians found that on average, vegetarians had a more depressed mood.
2) Data from 49,889 participants (8,057 vegetarians and 41,832 non-vegetarians) was included in the study.
3) It is impossible to work out whether depressive mood results in a better probability of becoming a vegetarian.
4) Results from previous longitudinal studies, however, indicate that psychological state issues like anxiety and depression precede dietary changes.
There is a posh relationship between our psychological state and what we eat. On the one hand, certain diets appear to extend the danger of developing a mental disturbance. On the opposite hand, being affected by a mental disturbance could lead to eating more or eating less, or eating different sorts of foods.
One particularly mysterious association is that between depression and being a vegetarian. While some studies showed that vegetarians are more depressed than meat-eaters, others showed the precise opposite.
A NEW META-ANALYSIS ON VEGETARIANISM AND DEPRESSED MOOD
To unravel this mystery, a German research team (which I am neighbourhood of) conducted a replacement meta-analysis on vegetarian diet and depression that has now been published within the Journal of Affective Disorders (Ocklenburg & Borawski, 2021). A meta-analysis may be a sort of statistical analysis that integrates the results of many different scientific studies. It has the advantage of bigger sample size, increasing statistical power, and rendering the analysis less likely to be suffering from characteristics of individual studies.
In the meta-analysis, data on individual scores in depression questionnaires from 13 different empirical studies that compared vegetarians and non-vegetarians were included. Overall, data from 49,889 participants (8,057 vegetarians and 41,832 non-vegetarians) were included within the analysis, making this an outsized and statistically robust analysis.
WHAT WERE THE RESULTS OF THE STUDY ?
The meta-analysis revealed a statistically significant difference between vegetarians and non-vegetarians, with vegetarians showing higher depression scores than non-vegetarians. Thus, vegetarians, on average, showed a more depressed mood than meat-eaters. But correlation is not causation—and from the association observed in the meta-analysis, it is not possible to determine whether depressive mood leads to a higher probability of becoming a vegetarian, or whether being vegetarian increases the probabilities of experiencing depressive episodes.
However, the results of a previous longitudinal study on vegetarian diet and depression, anxiety, and somatoform disorders suggest that depressive mood may come first (Michalak et al., 2012). In this study, it had been shown that a lot of people began to follow a vegetarian diet only after they got a diagnosis for a mental disturbance, not the opposite way around. Thus, a vegetarian diet might not cause depression in the least. Instead, it's going to be more likely that folks become vegetarian after developing psychological state issues. Michalak and co-authors (2012) suggested three possible reasons for this behaviour:
1) Individuals with mental health issues may change their diet to positively influence their mental health via a healthier lifestyle.
2) Individuals with mental health issues like depression may be more sensitive to the suffering of other beings, including animals. This increased empathy for animal suffering may cause them to prevent eating meat.
3)Individuals with mental health issues may be more anxious about their health in general; a vegetarian diet is often perceived as being healthier than eating meat.
Source
https://www.psychologytoday.com/us/blog/the-asymmetric-brain/202108/why-are-vegetarians-more-likely-be-depressed-other-people