“It’s the aromatherapy diffuser plant chemicals — the herbal components — that you take in through your skin or nose. These are what affect your body.” Essential oils are highly concentrated, so you only use a little at a time. They typically come in tiny bottles, which you can buy in pharmacies or health food stores. Inhaling its aroma by waving an open bottle under your nose or smelling a cloth containing a few drops of the oil Using a mister to spray it into the air or onto linens or clothing Diluting it with a carrier oil (a neutral oil, such as almond or grapeseed) and dabbing it onto your skin — so you can smell it when you need some relief Massaging diluted oil into your skin, particularly into a painful joint RELATED: Why You Should Fall in Love With Lavender (Infographic) How what you smell can change how you feel “When you rub an essential oil into your skin, you absorb it. It ends up in your bloodstream,” Dr. Powell says. “The same thing happens when you inhale the scent. Chemicals from the herb get absorbed through tissues in your nose and lungs.” These chemicals eventually reach your limbic system — the network of nerves in your brain that controls your instincts and emotions. “They can alter your perception of pain and potentially improve your mood,” Dr. Powell says.