There's definitely a common theme here that affects many people because we can see in the literature that vegetarianism and veganism are very strongly associated with mental disorders. And yet, I think that you could make a very strong case for even in a general population level, they're being nutrients that are in animal products that are very important for mental health.
Chris Masterjohn earned his PhD in Nutritional Sciences from the University of Connecticut in 2012. He served as a postdoctoral research associate in the Comparative Biosciences department of the College of Veterinary Medicine at the University of Illinois at Urbana-Champaign. From August 2014 to December 2016, he served as Assistant Professor of Health and Nutrition Sciences at Brooklyn College, part of the City University of New York.
To assess and ultimately fix any nutrient deficiencies you may have, check out his very thorough course, Testing Nutritional Status: The Ultimate Cheat Sheet. Use code GENIUS for 20% off.