More cats, more happiness? New study finds surprising link
A new study examining 93 countries found a positive statistical correlation between the density of domestic cats and national happiness scores. However, researchers also found a negative correlation between exposure to the Toxoplasma parasite, transmitted through cats, and happiness. The study emphasizes that this is a correlational, not causal, relationship, and that other factors, such as national wealth, may explain the link.
A new study examining 93 countries, including Israel, found a positive statistical correlation between the density of domestic cats and national happiness scores. Researchers calculated the number of domestic cats per 10,000 residents in each country and compared the data to happiness scores, GDP per capita, income levels, and health expenditures. The correlation coefficient between cat density and happiness stood at 0.62. However, a less cheerful side was also found: higher exposure to the Toxoplasma gondii parasite, for which cats serve as the definitive host, was negatively correlated with happiness. Researchers used IgM antibody data among pregnant women as an indicator of recent exposure. In a statistical model combining several variables, cat density and Toxoplasma exposure remained strongly correlated with happiness scores, explaining 47% of the variance. Surprisingly, no positive correlation was found between the number of cats and parasite exposure; it is possible that in wealthier countries, cats are kept indoors and receive veterinary care, reducing exposure. The researchers emphasize that this is an ecological and correlational study that does not prove causality, and that factors such as national wealth may explain the link.