A new review suggests a potential link between owning a cat during childhood and a higher risk of developing schizophrenia-related disorders later in life.
Australian researchers analyzed 17 studies conducted over the past 44 years across 11 countries. They found that individuals exposed to cats early in life may be twice as likely to show symptoms associated with schizophrenia.
The Parasite Connection
The suspected link centers around Toxoplasma gondii, a microscopic parasite commonly found in cats. This parasite can spread through undercooked meat, contaminated water, or direct contact with infected cats. While it often causes no symptoms, T. gondii may reach the brain and interfere with chemicals involved in mood and cognition.
Dr. John McGrath, who led the study, noted that cat exposure appeared to double the risk of schizophrenia-related symptoms. Still, he emphasized that more research is needed to understand the connection.
Not All Studies Agree
The researchers stressed that correlation does not equal causation. Some studies found no link between cat ownership and mental illness. One even showed that people bitten by cats scored slightly higher on some psychological tests—but that alone doesn’t prove a cause.
Study quality also varied, and researchers haven’t pinpointed the most vulnerable age for exposure. However, they believe the critical period may be between 9 and 12 years old.
Other Suspects
Scientists are also considering other possible culprits, like Pasteurella multocida, a bacterium found in cat saliva. Though it’s too early to draw conclusions, researchers are keeping it on their radar.
No Cause for Panic
Experts say there’s no reason for cat owners to worry. Owning a cat does not guarantee mental illness. What’s needed now is more high-quality research to explore how environmental factors, including pets, might affect the brain.
The Bigger Picture
Cats are beloved companions, but they may also offer clues to understanding mental health. This line of research could help scientists find new ways to prevent and treat psychiatric disorders in the future.
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