As a significant link in the mind-body connection, the sense of smell can be deployed to improve pain tolerance. Any pleasant smell can act as a distraction and lift mood, but recent studies suggest that sweet smells may work best. "Sweet tastes reduce pain by activating opioid systems in the brain, and the odor comes to activate the same systems," says Australian psychologist John Prescott, currently a visiting scholar at Oxford University.
You can also use your sense of smell to deliver instant relaxation, says Pamela Dalton, a sensory psychologist at the Monell Chemical Senses Center, in Philadelphia. Pick a distinctive odor, then pair that aroma with a calming meditation session. After a few sessions, the odor itself will elicit a relaxed state, even when you don't have time to meditate.
Check out this and other pieces on the power of scent at Psychology Today.