The link between depression and meatless diets

In September of 2022, a team led by Ingrid S. Cole at a University in Brazil published a report citing that over 14,000 Brazilians were studied to assess the association between meatless diets (such as vegetarianism and veganism) and depressive episodes.

The participants were ages 35-74 years old, and were asked to complete a "food frequency questionnaire" to determine those who did and did not regularly consume meat.

Participants also used a method called the Clinical Interview Schedule-Revised (CIS-R) to determine mental health problems such as depression and anxiety.

Other factors such as smoking, alcohol consumption, physical activity, health status and daily energy intake were all also measured and factored in.

The results show that depressive episodes occurred more commonly among those with a meatless diet. They experienced roughly two times as many depressive episodes compared to those who ate meat regularly.

These results were proven factoring in socioeconomic factors, lifestyle, and even malnutrition. But it seems that regardless of these, those with meatless diets were still more likely to experience more frequent depression.

One factor that wasn't considered by the study, is a major reason why many may ascribe to a meatless diet - empathy. Those who do not eat meat due to empathy for animals, along with those who stress more about what they should eat may be more prone to depression.

Similar studies were done in 2020, 2021 and 2022 - all attempting to find the connection between meat consumption and depression, but they were met with mixed results.

Longitudinal studies of participants over time will definitely be needed. Scientists call the association unclear due to mixed results, however at this point it seems there is at least some correlation between depression and meatless diets.

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