Of the five senses, smell remains perhaps the most mysterious. Our knowledge of the olfactory system—which helps the brain recognize, categorize, and memorize a multitude of smells—has lagged behind our understanding of sight, hearing, taste, and touch. For centuries, we have used aromas—derived from the Greek word for sweet spice—to promote emotional and physical well-being. In fact, research supports the many benefits of the ancient healing art of aromatherapy.
When we use our sense of smell, our autonomic nervous system—the body’s autopilot—produces all kinds of physical reactions. The amygdala, the brain’s emotional center, is intimately connected to the olfactory system and immediately influenced by scents. This explains the butterflies swarming in our stomachs when we smell a pleasant scent from our childhood or the panic some people experience after catching a whiff of alcohol when entering the doctor’s office or hospital.
Aromatherapy takes advantage of the powerful link between nose and brain by using fragrant plant essences known as essential oils. These oils are made by expressing or distilling natural plant material to yield a highly concentrated aromatic essence. On average, an essential oil is 50 to 70 times more potent than the nondistilled plant from which it was made. Because they are so highly concentrated, pure essential oils are rarely used on the skin. Instead, small quantities are diluted, usually with a vegetable base oil.
Each oil triggers the olfactory system with unique combinations of chemicals. Applied on the skin or sampled in whiffs in or near the nasal passages, some fragrances soothe and relax, while others stimulate and invigorate (see below). For example, vanilla and flowery scents can reduce the sensation of pain, but spicy smells tend to heighten it. In a recent clinical trial, releasing coconut fragrance in the room while challenging volunteers with math questions blunted their stress levels.
Interestingly, scientists say that the response to aromas is influenced by ethnic background, memories, and newly discovered variabilities in the olfactory system. Some may sense a pungent odor even though everyone else loves that particular scent. In others, a scent leaves a bad aftertaste—as is true of vanilla in a surprisingly large number of people who participated in a clinical trial.
Aromatherapy, like much in the field of healing, must be customized to one’s personal needs. Experiment with scents to identify which ones appeal to you, and to develop your own pharmacopoeia to pep you up or allow you to relax. Keep in mind that essential oils are less likely than synthetic aromas to produce an allergic reaction. If you have multiple allergies, however, talk to your doctor before using essential oils. For more about aromatherapy and to find an expert near you, contact the National Association for Holistic Aromatherapy (naha.org).
The Basics of Essential Oils
Coconut reduces stress
Geranium helps balance female hormones
Ginger alleviates nausea
Lavender promotes sleep
Lemon enhances the immune system
Marjoram eases anxiety
Peppermint stirs mental concentration
Rose and Jasmine lift depression
Rosemary boosts memory recall and energy
Vanilla soothes discomfort
Ylang Ylang helps dispel anger
Essential oils are widely available. Opt for products with labels that state the plant’s Latin name and “essential oil” rather than “fragrance oil,” “perfume oil,” or “nature identical oil.”
Mehmet Oz, M.D., best-selling author and host of The Dr. Oz Show, is a leading expert in heart transplant surgery, complementary medicine, and health care policy at New York-Presbyterian Hospital.