Having a cat as a pet is linked to an increased risk of schizophrenia-related conditions, according to a 2023 analysis of 17 studies. This idea that cat ownership could be linked to schizophrenia risk was proposed in a 1995 study , with exposure to a parasite called Toxoplasma gondii suggested as a cause. But the research since then has delivered mixed conclusions. The 2023 review found "a significant positive association between broadly defined cat ownership and an increased risk of