(Headline USA) A new meta-study by researchers from the University of Queensland, Australia found that owning a cat could increase the risk of schizophrenia in young adults, OANN reported.
The team conducted a review of 17 studies from 11 countries, including the U.S. and the United Kingdom, published over the last 44 years. They found that young adults exposed to cats had approximately twice the odds of developing schizophrenia before the age of 25.
Could owning a cat increase the risk of developing schizophrenia?
In 1995, Fuller Torrey proposed this hypothesis, citing exposure to Toxoplasma gondii as a possible cause.
Our report summarizes data collected over the past four decades on this topic https://t.co/5fBUXgBVSe pic.twitter.com/yVQu0AEp36
— John McGrath (@John_J_McGrath) December 3, 2023
The researchers argued the link is likely due to a parasite commonly found in cats called Toxoplasma gondii, which can enter the body’s bloodstream via a bite.
The parasite can then enter the central nervous system and affect neurotransmitters in the brain, potentially causing personality changes, psychotic symptoms and even disorders such as schizophrenia.
The study confirmed this potential cause by directly comparing subjects who had been bitten by a cat to those who had not been bitten. Those who had been bitten had higher scores on the schizotypy scale, which is a questionnaire that measures traits of disorganized patterns of thinking, according to the researchers.
Other scientists have criticized the review, arguing it did not properly account for other factors, such as economic background and family history.
For example, it has been well documented that young men are more susceptible to schizophrenia, with symptoms usually appearing when they are in their 20s.
Another recent study found a potential link between schizophrenia and marijuana use. Daniel Levey, a medical neuroscientist at Yale and the co-author of the study, said he and his team were able to identify genome regions linking cannabis addiction to “psychiatric disorders, abuse of other substances such as tobacco, and possibly even an elevated risk of developing lung cancer.”
The researchers went on to warn that widespread marijuana legalization could have “substantial public health risks if the usage increases.”