Your cat may not smell bad, but it can definitely endanger your life! Now, researchers have suggested that owning a cat could double a person’s risk of developing schizophrenia-related disorders.
Researchers from the Queensland Mental Health Research Center in Australia examined data spanning 44 years and 11 countries, including the US and the UK, and found a significant link between exposure to cats and subsequent diagnoses of psychotic illnesses.
This meta-analysis, published in Schizophrenia Bulletin, found a “significant positive association” between cat ownership and an increased risk of schizophrenia-related disorders.
Schizophrenia affects the way a person thinks, feels and behaves, so uncovering potential environmental factors is essential to advancing both prevention and treatment.
After adjusting for other variables, the researchers report that people exposed to cats were about twice as likely to develop psychotic illnesses later compared to those who were not exposed.
Despite the strong claim of “duplication,” the review has important caveats. First, the timing of exposure might matter. One study looked at cat ownership in childhood (ages 9 to 12) and found stronger associations than when measured at broader ages, suggesting a critical exposure window, which is not yet well defined.
In another study, those who reported being bitten by a cat showed more psychotic traits, but the researchers speculated that other pathogens (such as Pasteurella multocida) might be at play, not just T. gondii.
One of the key hypotheses behind this link involves Toxoplasma gondii, a parasite commonly carried by cats. This organism can be transmitted through cat feces, bites, or even undercooked meat and contaminated water.
Once inside the body, T. gondii can infiltrate the human brain and influence brain function, potentially triggering personality changes, psychotic symptoms, or psychiatric disorders.
For now, the new meta-analysis does not prove that cat ownership causes schizophrenia; it simply points to a possible risk factor.
The researchers themselves call for more rigorous, large-scale studies that use representative samples to better understand the relationship.
In addition to suggesting that people exercise caution, this research adds a new dimension to the way scientists think about environmental risk factors for mental illness.
Mental health does not depend purely on genetics; Infections, immune system interactions, and even owning a pet can play a role. If the link is confirmed in future research, it could influence public health advice on pet care, especially for young people or families with a history of psychosis.