Every time you turn around someone is suggesting aromatherapy. Essential oils are a $1 billion industry, but are they effective? Here's what scientific research has to say.
Your friend suggests that you use a lotion infused with peppermint essential oil to help combat your nausea. Your coworker insists that he has never slept so well since starting to sprinkle a little lavender oil on his pillow at night. Last year alone consumers in the United States spent $1 billion on essential oil products and is expected to exceed $11 billion by the year 2022. But what does the research say? Do essential oils really work?
What is aromatherapy?
Essential oils are oils, typically fragrant ones, that have been extracted from the roots, flowers, leaves, or seeds of plants using steam or applied pressure. The qualifier “essential” refers to the fact that the oil contains the “essence” of the plant (i.e. the natural chemicals that provide a distinct odor or flavor). In the practice of aromatherapy, these oils—once diluted—are applied to the skin, smelled, dabbed on a pillow or in a bath, or heated so that their aroma is dispersed into the air. Some soaps and lotions can also be made with essential oils and used as aromatherapy products.
The use of essential oils is cross-cultural and dates back thousands of years. Many know the story of frankincense being offered as one of the gifts of the Magi. Even if you haven’t purchased an essential oil roller or diffuser, chances are you may have used them anyway. Vick’s Vaporub, typically rubbed on the chest as a cough suppressant, contains the essential eucalyptus, cedarleaf, and nutmeg oils (among others) suspended in petroleum jelly.
Do essential oils and aromatherapy work?
The National Institute of Health provides a thorough summary via the US National Library of Medicine of research conducted into the efficacy of essential oils. Currently, there is no evidence-backed research showing any illnesses that can be cured through the use of essential oils or the practice of aromatherapy. The results on the other possible benefits of essential oils as, for example, mood elevators or stress relievers, are more mixed. But most are still inconclusive.
One of the scientific studies that have revealed positive results from essential oils involves patients with dementia. Although, contrary to common lore, drinking a tablespoon of fish oil every day won’t likely stave off dementia, there is evidence that balm from lemon oil reduces agitation in patients with dementia according to a study in the Journal of Clinical Psychiatry.
There are other proven success stories for essential oils, such as the treatment of acne with tea tree oil and the treatment of alopecia areata or hair loss with oils like thyme, rosemary, lavender and cedarwood.
Research into the use of essential oils found in citrus fruits is particularly intriguing due to their natural antibacterial qualities. For example, citrus oil, particularly when combined with Dead Sea salts, was shown to inhibit bacterial growth in mice and act as an anti-inflammatory agent. The citrus essential oil bergamot could help fight the growth of common causes of food poisoning like listeria, e coli, and staphylococcus.
Before you spend $40 on a 15-mL bottle, you might want to try a scented candle first.
However, most of these studies have not yet extended to clinical trials, meaning there is still much more work to do before essential oils would be potentially prescribed by physicians. Given the strong public interest in essential oils, whether it be to target things other medicines have so far failed to fix (like migraines, anxiety, stress, insomnia, and memory) or to control what goes into their medicine cabinet without a prescription, more research into the possible benefits of essential oils is clearly worthwhile.
There are very few noted side effects associated with the use of essential oils, although in the US they do not require approval from the FDA. One exception is the estrogen-like effects noted for lavender and tea tree oils which have been linked to breast enlargement in pre-pubescent boys when applied over long periods of time.
So if you’re looking to relieve stress, adding a few drops of diluted essential oils to a warm bath probably doesn’t hurt. But before you spend $40 on a 15-mL bottle, you might want to try a scented candle first.
GET MORE Ask Science
Until next time, this is Dr. Sabrina Stierwalt with Ask Science’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Ask Science on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at email@example.com. Get fascinating science insights delivered to your inbox by subscribing to the monthly Ask Science newsletter.