LAVENDER’S SOOTHING SCENT COULD BE MORE THAN JUST FOLK MEDICINE
People like lavender. We have been using this violet-capped herb since at least medieval times. It smells nice. But Google “lavender” and results hint at perhaps the real fuel for our obsession: “tranquility,” “calm,” “relaxation,” “soothing” and “serenity.” Lavender has purported healing powers for reducing stress and anxiety. But are these effects more than just folk medicine?
Yes, said Hideki Kashiwadani, a physiologist and neuroscientist at Kagoshima University in Japan — at least in mice.
“Many people take the effects of ‘odor’ with a grain of salt,” he said in an email. “But among the stories, some are true based on science.”
In a study published recently in the journal Frontiers in Behavioral Neuroscience, he and his colleagues found that sniffing linalool, an alcohol component of lavender odor, was kind of like popping a Valium. It worked on the same parts of a mouse’s brain, but without all the dizzying side effects. And it did not target parts of the brain directly from the bloodstream, as was thought. Relief from anxiety could be triggered just by inhaling through a healthy nose.
Their findings add to a growing body of research demonstrating anxiety-reducing qualities of lavender odors and suggest a new mechanism for how they work in the body. Kashiwadani believes this new insight is a key step in developing lavender-derived compounds like linalool for clinical use in humans.
In this study, researchers exposed mice to linalool vapor, wafting from filter paper inside a specially made chamber to see if the odor triggered relaxation. Mice on linalool were more open to exploring, indicating they were less anxious than normal mice. And they did not behave like they were drunk, as mice on benzodiazepines, a drug used to treat anxiety, or injected with linalool did.
But the linalool did not work when they blocked the mice’s ability to smell, or when they gave the mice a drug that blocks certain receptors in the brain. This suggested that to work, linalool tickled odor-sensitive neurons in the nose that send signals to just the right spots in the brain — the same ones triggered by Valium.
Though he has not tested it in humans, Kashiwadani suspects that linalool may also work on the brains of humans and other mammals, which have similar emotional circuitry.