Researchers in Germany found higher depression scores among those on a vegetarian diet than non-vegetarians, suggesting a link between depression and vegetarianism.
Although mental health disorders can affect one’s diet, what we eat can also affect the development of certain mental disorders. Moreover, with veganism and vegetarianism gaining popularity among the masses, researchers are intrigued by the effect of various diets on an individual’s mental health. Conflicting reports are present in the literature on the link between a vegetarian diet and depression. While some point the diet as a possible factor in the development of depression, others have shown an opposite effect. To analyze the link further, a team of German researchers conducted a large-scale meta-analysis.
A meta-analysis is a statistical analysis that combines the results of different scientific studies to derive an association. Researchers Sebastian Ocklenburg and Jette Borawski looked at several different studies comparing vegetarians and non-vegetarians. They aimed to determine an association between depression scores and a vegetarian diet. After removing duplicates, and applying the inclusion criteria, the researchers ended up with a total of 13 studies. The studies provided data on participants’ depression scores and their diet. Overall, it included data from a total of 49,889 participants: 41832 non-vegetarian and 8057 vegetarians.
The results of the analysis are available in the Journal of Affective Disorders.
Meat-eaters vs Non-Meat-Eaters
The meta-analysis revealed a significant increase in the depression scores of vegetarians compared to non-vegetarians. However, the authors of the study state that their analysis is not enough to draw a conclusion. There is not enough information to determine causation. It is unclear as to whether people with higher scores started their vegetarian diet before or after the onset of their symptoms.
Previous studies have shown that the development of mental health issues often makes a person more diet conscious. Thus, leading them towards vegetarianism. Furthermore, such individuals have greater empathy for animal cruelty and often stop eating meat. However, all these theories are purely speculative at the moment.
Moreover, the studies included in the analysis had low geographic variation and high heterogeneity. Thus, causing limitations in forming conclusions. Therefore, the authors of the study call for further research for the establishment of a link.
Reference:
Ocklenburg, S., & Borawski, J. (2021). Vegetarian diet and depression scores: A meta-analysis. Journal of Affective Disorders, 294, 813–815. https://doi.org/10.1016/j.jad.2021.07.098
Michalak J, Zhang XC, Jacobi F. (2012). Vegetarian diet and mental disorders: results from a representative community survey. Int J Behav Nutr Phys Act, 9, 67.
