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Living with cats as a child has once again been linked to mental health disorders, because our furry friends apparently can't catch a break.

In a new meta-analysis published in the journal Schizophrenia Bulletin, Australian researchers identified 17 studies between 1980 and 2023 that seemed to associate cat ownership in childhood with schizophrenia-related disorders — a sample size narrowed down from a whopping 1,915 studies that dealt with cats during that 43-year time period.

As anyone who's read anything about cats and mental health knows, there is a growing body of evidence suggesting that infection from the Toxoplasma gondii parasite, which is found in cat feces and undercooked red meat, may be linked to all sorts of surprising things. From mental illness to an interest in BDSM or a propensity for car crashes, toxoplasmosis — that's the infection that comes from t. gondii exposure — has been thought of as a massive risk factor for decades now, which is why doctors now advise pregnant people not to clean cat litter or eat undercooked meat.

Toxoplasmosis has been linked in particular to schizophrenia and related disorders, which are characterized by hallucinations, delusions, and chaotic thinking and behavior. To be clear, nobody knows exactly what causes schizophrenia, but the psychiatric community's best-educated guesses suggest that a combination of genetics, brain development disruptions, and environmental factors are risk factors for these often-debilitating disorder — and being exposed to t. gondii via cats while one's brain is developing does seem, per lots of studies, to be among the latter.

Using multiple databases, the scientists out of Australia's Queensland Centre for Mental Health Research found that there was a whopping 2.24 ratio for developing schizophrenia-related disorders and owning a cat. In English, this means that per their deep dive into a bunch of academic studies, people may be more than two times as likely to develop schizophrenia-related disorders if they owned cats during childhood than if they don't.

While that's a pretty significant figure, the researchers pointed out that there needs to be much more study to figure out what ages are the riskiest, because the studies they identified were, unsurprisingly, all over the place.

"Our field needs to generate novel candidate environmental risk factors, especially those that are potentially modifiable," the researchers wrote in their paper. "Within that context, there is a need for more high-quality studies, based on large, representative samples to better understand cat ownership as a candidate risk-modifying factor for mental disorders."

Translation: there need to be way more studies to figure out what exactly about toxoplasmosis seems to be a risk factor for mental illness. Until that happens, though, these bizarre correlations will likely continue to emerge.

More on weird fungus: Scientists Intrigued by Carnivorous Fungus That Devours Worms

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