Most people associate food poisoning with physical symptoms, but new research shows a connection between a foodborne parasite and mental/emotional problems, including suicide. ScientistMicroscopeMain Researchers at universities across the country analyzed data collected from 1991 through 2008 and confirmed a relationship, previously theorized, between Toxoplasma gondii (T gondii) and self-directed aggression and other psychiatric disorders, according to their findings published in The Journal of Clinical Psychiatry. “These data are consistent with previous studies suggesting a relationship between T. gondii and self-directed aggression — i.e. suicidal behavior — and further add to the biological complexity of impulsive aggression both from a categorical and a dimensional perspective,” the scientists concluded. Although many people associate Toxoplasma gondii with cats, which can transmit the parasite to humans, the researchers and the Centers for Disease Control and Prevention report it is often spread to people via foodborne routes. Specifically, consumption of undercooked meat from animals infected with the parasite is commonly the cause of human T gondii infections, which the CDC reports is a “top cause” of foodborne illness in the United States. By examining the data collected from patients during the 17-year period, the researchers found that people who had evidence of T gondii infection were as much as twice as likely to exhibit aggression and impulsive behaviors, including suicide. The data on human behavior is supported by previous studies with rats and mice that also showed increased impulsive aggressive behavior in rodents with T gondii. Infected mice actually lost their aversion to felines and sought out interaction with their natural enemy, which scientists interpreted as increased and impulsive risk-taking behavior. That behavior is considered suicidal for the mice and beneficial for the parasite, which likes to reside in cats. Regardless whether the host animal is a mouse or a human, the parasite attacks the brain. Once in the brain, the parasite “hides within neurons and glial cells, forming characteristic cystic intracellular structures under the pressure of the immune system,” according to the research report. (To sign up for a free subscription to Food Safety News, click here.)