You may soon come to love catnip as much as your cat. New research suggests the chemicals derived from catnip and silver vine, an even more potent plant that grows in the mountains of Japan and China, can ward off pesky mosquitoes. Masao Miyazaki, a biologist at Japan's Iwate University, spent five years examining catnip and silver vine, eventually unearthing a silver vine chemical called nepetalactol, which is similar to but more potent than nepetalactone, the key compound in catnip. When paper pouches full of nepetalactol were put in cages with 25 domestic cats, 30 feral cats, and a five big cats housed at zoos, most felines went nuts for the stuff, rubbing against it for 10 minutes on average, while ignoring an unlaced pouch, per Science. This resulted in elevated levels of beta-endorphins, also known as the "happiness hormone," researchers say.
But they were interested to know whether there was more to the feline obsession than pleasure. And the findings suggest that "rolling [in nepetalactol] is rather a functional behavior," says Miyazaki, whose study appears in Science Advances. Working off previous research showing nepetalactone could be as effective a mosquito repellant as DEET, per the New York Times, Miyazaki's team applied nepetalactol and a neutral substance to cats, then exposed them to hungry mosquitos, finding half as many insects landed on the cats treated with nepetalactol. Researchers therefore suggest cats "use plant metabolites for protection against insect pests." While it doesn't necessarily explain why cats love plants like catnip, this potential benefit might apply to us. Per Science, the team has already patented an insect repellent based on the research. (Read more discoveries stories.)