Stopping to smell the roses is a good mantra to encourage you to take the time to appreciate what’s around you. Stopping to smell the lemons might not have the same ring to it, but scientists in Japan have shown how doing just that can actually alter gene activity and blood chemistry in ways that measurably reduce stress.

The use of fragrant plant oils to improve mood and health has been around since ancient times and more recently aromatherapy has become a popular form of alternative medicine. One of the most widely used substances used in aromatherapy to soothe away emotional stress is linalool, a chemical found in citrus fruits, lavender, sweet basil, birch trees and other plants. And now science has shown why.

The scientists exposed lab rats to stressful conditions (presumably getting them to do some public speaking) while inhaling and not inhaling linalool. Those exposed to linalool saw stress-elevated levels of neutrophils and lymphocytes - key parts of the immune system – return to near-normal levels and a reduction in the activity of more than 100 genes that go into overdrive in stressful situations.

The researchers say their findings could form the basis of new blood tests for identifying fragrances that can soothe stress.

The team’s findings can be found in the American Chemical Society’s Journal of Agricultural and Food Chemistry.