Essential oil and immune support: many claims, limited study

DEAR DR. ROACH »

Many of my friends assert that the use of essential oils “supports” their immune system and reduces their risk of getting sick. They diffuse them into the air at home, add them to water or tea and apply them to the soles of their feet. Are there studies to back up these claims?

ANSWER » There are studies that show that, in some cases, essential oils stimulate some of the body’s immune cells. Blood levels of immunoglobulins, cytokines and other molecules that indicate a robust immune response can increase with exposure to essential oils.

However, no studies show what I would want to see before recommending their use in general, which is that people who use essential oils have less infections or less disease than people who don’t. In an ideal world, it would be great to know who should use what essential oils, and under what conditions. Many sources provide such advice, oftentimes conflicting, but none is supported by the kind of evidence I would accept.

Further, the immune system is not something you can dial up or dial down, nor would you want to. There is always a balance between a powerful defense against invaders like bacteria, viruses and cancer cells — things we want our immune system to fight off — and the negative effects of overzealous activity, such as allergies and autoimmune diseases. Science currently lacks the knowledge to precisely improve the good parts of the immune system while at the same time reduce the harm an overactive immune response can cause.

Some essential oils may be absorbed through the skin, but these can have negative as well as positive effects. The ability to use essential oils as medicine is limited. With increasing scientific study, we may learn more about how better to use this large and complex group of compounds.

Essential oils have been shown to have benefits when used as aromatherapy, reducing anxiety in some studies.

Keith Roach