Last year, cat owners got a scare when a team of French researchers reported a possible link between felines and brain cancer. Cat feces can harbor a single-celled parasite called Toxoplasma gondii, and the scientists found that nations with higher rates of human T. gondii infection also have higher incidences of brain cancer. The findings were controversial, and many scientists considered the link weak. Now, another team of researchers believes it has settled the issue. The scientists examined a cohort of more than 600,000 British women aged 50 and older and tracked how many developed brain tumors over an average of 3 years. Eighteen percent of those women—more than 100,000—owned at least one cat. But the cat-owning women were no more likely to develop brain cancer than their cat-free counterparts, despite their presumably greater risk of exposure to T. gondii, the team reports online today in Biology Letters. So the next time someone scratches up your furniture, blame the cat—but when it comes to brain cancer, point the finger somewhere else.
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