Plant-based meat alternatives linked to increased risk of depression in vegetarians, study finds

Vegetarians consuming plant-based alternatives to meat -- suggested as one of the means to lower the environmental impact of meat consumption -- could have a 42 per cent increased risk of depression compared to vegetarians who refrain from them, according to a study.

Published in the journal Food Frontiers, the study also found higher blood pressure and inflammation levels, along with lower levels of ‘good’ cholesterol (HDL), in vegetarians who ate plant-based meat alternatives.

Researchers at the University of Surrey, UK, analysed data from over 3,300 vegetarians in the UK Biobank—about half were consumers of plant-based meat alternatives, and half were non-consumers.

Made using plant-based proteins such as soy, plant-based meat alternatives (PBMA) are considered a potential solution for sustainability, as fewer natural resources such as water, land and energy are required to produce them compared to animal meat.

However, these meat alternatives are also considered 'ultra-processed foods,' as chemicals are often added to make them taste like meat.

The researchers noted that while consuming plant-based meat alternatives was not linked with clear health benefits, more studies are needed to investigate concerns related to inflammation, which may arise from eating these products.

"In conclusion, while no clear health risks or benefits were associated with PBMA consumption in vegetarians, the higher risk of depression, elevated CRP (C-reactive proteins), and lower apolipoprotein A levels (HDL cholesterol) in consumers of PBMA suggest potential inflammatory concerns that warrant further investigation,” the authors wrote.

Co-author Anthony Whetton, a professor of translational biosystems at the University of Surrey, said, "Ultra-processed plant-based meat alternatives can be a useful way for people to transition to a vegetarian diet effectively, which helps with sustainable agricultural practices."

"Further research, including longitudinal studies and trials with more diverse populations, is necessary to confirm these findings and the relationship between vegetarian foods and mood," Whetton added.

In the study group, the researchers found no notable differences in the intake of sodium, free sugars, total sugars, or saturated fatty acids between vegetarians who ate plant-based meat alternatives and those who did not.

The team also found that consuming plant-based meat alternatives was linked to a 40% lower risk of irritable bowel syndrome.

"The overall findings are reassuring, suggesting that plant-based meat alternatives may be a safe option when they are part of an overall balanced diet. However, the potential link between these foods, inflammation, and depression warrants further investigation," said senior author Nophar Geifman, a professor of health and biomedical informatics at the University of Surrey.