Green smells good for you

With spring often comes the misery of allergies. But new research shows that the smell of green leaves is actually good for your health.

A recent Japanese study found that, under stressful conditions, “green odour” can bring down rising blood pressure and help skin temperature to recover.

These findings, published in the January 15 issue of the BioPsychoSocial Medicine journal, suggest that “green odor has an anti-stress effect in healthy humans,” wrote the researchers.

In one experiment, 11 adults with normal blood pressure smelled a chemical concentration of the leafy scent while plunging their right hand in icy, slushy water for a minute. (This is called a cold-pressor test, a cardio challenge to increase blood pressure.)

As it turned out, participants sniffing green odour had smaller changes in blood pressure than when smelling an odourless substance. Green odour also appeared to help their skin temperature recoup during the test.

While the Japanese study involved only 19 participants, it isn’t the first piece of research to suggest the benefits of green odour. Another one from 2005 found that it has an anti-fatigue effect in humans.

Researchers hope their findings will be especially useful aromatherapy for people with high blood pressure during psychological stress.

Interestingly, while most of the study participants said the green odour was pleasant, they described higher concentrations of it as too strong and unpleasant. Next, the researchers are planning to find out the maximum concentration of green odour that will elicit an anti-stress effect but still smell good.