This Week In Wellness a large meta-analysis published in Critical Reviews in Food Science and Nutrition show that meat abstention, in other words, vegetarianism or veganism is “clearly associated with poorer mental health, specifically higher levels of both depression and anxiety”, whilst meat consumption is associated with “lower levels of depression and anxiety”.

https://www.psypost.org/2021/11/meat-consumption-is-associated-with-better-mental-health-meta-analysis-finds-62107

https://www.tandfonline.com/doi/full/10.1080/10408398.2021.1974336