Is cat poop changing your personality? Here's what the research says

We all have at least one friend who posts nothing but cat pictures to their social media feeds and can't make it through lunch without at least a few stories about their beloved feline.

Maybe that friend is you. We aren't here to judge.

But there might be more causing that love than just the intelligence of cats and their uncanny ability to sing absolute bops about how sometimes they're alone that take over the internet.

It could be a parasite that lives in cats and is shed in their fecal material that has been shown to alter behavior and feelings towards cats.

World Veterinary Day: 4 facts to think about on your next vet visit

What is Toxoplasma?

Toxoplasma gondii is a microscopic parasite that cats get by eating infected rodents, birds or other small animals, or anything contaminated with feces from another cat that is shedding the parasite, according to the Centers for Disease Control.

After a cat has been infected, it can shed the parasite for up to two weeks, the CDC says. The parasite becomes infective one to five days after it is passed in the feces of the cat. The parasite can live in the environment for many months and contaminate soil, water, fruits and vegetables, areas where animals graze for food, and any place where an infected cat may have defecated, the CDC says.

Toxoplasmosis in humans

More than 30 million people in the United States alone carry the Toxoplasma parasite, according to the CDC, and the resulting infection is called toxoplasmosis.

Staggeringly, at least a third of the world's population is thought to have toxoplasmosis making it one of the most successful parasitic organisms in the world.

The infection can be dangerous during pregnancy, and also in babies, the immunocompromised, and other at-risk groups, but most healthy people will experience no symptoms or a mild flu-like illness.

Suggested ways to avoid infection include changing the litterbox daily, avoiding strays (especially kittens) and getting a blood test to check for the parasite if you are in one of the at-risk populations and suspect you've been exposed. You should also avoid eating undercooked meat, as it can also be present in farm animals.

Now on to the weird part.

Cat behavior: Here are 5 weird things your cat is doing and why.

Parasite changes behavior

A study published by the Royal Society showed that rats infected with the parasite lost their fear of cats, and in some cases actually became more attracted to them and the areas they frequented.

While rats normally would avoid areas that had signs of cat activity, those with the parasite showed the opposite behavior.

"This ubiquitous parasite subtly alters the brain of its intermediate host to enhance predation rate whilst leaving other behavioural categories and general health intact," according to the study by M. Berdoy, J.P. Webster and D.W. Macdonald.

More simply put, the parasite appears to increase the dopamine levels in the brain and creates a desire to be closer to cats. This has obvious benefits for the parasite, which can only proliferate in the intestines of cats, but uses other hosts like humans and animals to help spread and complete its life cycle.

Home in Indiana: In this corner of Bates-Hendricks, stray cats find their homes

Check out the video below from TEDEd for more on what we know about the world's most successful parasite.

Effects on humans

So is the parasite behind your love of cats? It's complicated.

According to a 2011 study found in the National Library of Medicine, the parasite, "Has cumulative effects on the behaviour of hosts, including humans.

"While most behavioural effects of toxoplasmosis were confirmed also in humans, neither the fatal attraction phenomenon nor any toxoplasmosis-associated changes in olfactory functions have been searched for in them."

The study did find that infected men rated the smell of cat urine as more pleasant than uninfected men (gross), but found the opposite trend in women.

"I don't think we can take it for granted anymore that these parasites are sitting in our heads for the rest of our lives doing nothing," Bill Sullivan, a professor of pharmacology and toxicology and microbiology and immunology at the Indiana University School of Medicine, told IndyStar in a 2015 article.

So while it doesn't appear there have been any more recent studies that have furthered the research behind this, it has been found since the initial report that those infected can be more willing to take certain risks, and are actually more likely to be involved in car accidents.

Those infected also become entrepreneurs at a higher rate than the general uninfected public, according to a 2020 study published in the Sage Journals.

So next time you cuddle up with your favorite furball, just know there may be more to your motivation than just hearing some purrs.

This article originally appeared on Indianapolis Star: Is cat poop changing your personality? Here's what the research says