I did some nutritional research. There are plenty of different causes of schizophrenia. One of them is long-term vitamin B12 deficiency. B12 is primarily found in meat and dairy. But can also be in the form of cyanocobalamin (derived from bacteria/fungi) for vegetarians/vegans. It may not entirely help, but supplementation of B12 or eating more meat can be a stepping stone. Another key B vitamin that helps B12 metabolization is B9 (folate, folic acid). Use of a multivitamin alongside improved diet can help with many health conditions.