Aromatherapy: what it is and what is known

Aromatherapy is the use of essential oils, the concentrated fragrant parts of plants, by breathing them in or applying them diluted to the skin, often during a massage. People usually try it to relax, ease stress or feel more comfortable during illness. The evidence is limited: studies are few, small and mixed, so any benefit beyond pleasant relaxation is uncertain.

What it is

Essential oils come from flowers, leaves, bark, peel, seeds or roots. They are released by crushing the plant or by steam. Proponents trace the use of aromatic oils back thousands of years, including to ancient Egypt. The modern practice began in the early 20th century, when the French chemist and perfumer René Gattefossé coined the word “aromatherapy” and published a book of that name in 1937.

Practitioners say that inhaling or applying essential oils can support physical, mental and spiritual wellbeing. In their account, smell acts on the brain’s emotional centers, while oils absorbed through the skin act on the body.

People commonly seek aromatherapy for relaxation, stress and anxiety, sleep, and comfort during serious illness. That includes nausea, low mood or pain during cancer care, where it is often offered as a complementary therapy.

What a session is like

You can use essential oils on your own, with a diffuser, a few drops on a tissue, steam, a bath or a lotion. Many people meet aromatherapy through aromatherapy massage, where the oils are diluted in a carrier oil and worked into the skin.

A massage session starts with questions about your health, lifestyle and history. The therapist then chooses oils for your needs, and you may help choose. The massage itself usually lasts 60 to 90 minutes, sometimes with soft music, and most people find it relaxing and soothing.

Before booking, it is worth asking:

• How many years of training they have and how long they have practiced
• Whether they have trained to work with people with your condition
• Whether they are insured

What research says

The research is thin and mixed. The US National Center for Complementary and Integrative Health (NCCIH) says it is not known whether aromatherapy helps with insomnia, because little rigorous research has been done. In one study of people under stress, lemon scent improved mood, but neither lemon nor lavender changed stress indicators, immune markers or pain control.

Most studies have been in people with cancer. The US National Cancer Institute reports that some found better mood, sleep, anxiety, nausea or pain, while others found no change. In a randomized trial of 313 people having radiation therapy, inhaled oils made no difference to anxiety or depression. Massage with Roman chamomile oil reduced anxiety in one study of 103 patients, while massage alone did not. Inhaled ginger oil somewhat reduced acute nausea during chemotherapy but not vomiting.

Cancer Research UK says aromatherapy might help some symptoms as a complementary therapy, but many studies were small and more research is needed. It also says there is no evidence it can prevent or treat cancer. A 2018 review of Cochrane evidence on integrative practices concluded that aromatherapy does not seem to be supported by Cochrane evidence.

Who should be careful

Essential oils have few side effects when used as directed, but they are strong. Undiluted oils can cause severe skin damage, and long skin contact can cause irritation or allergic reactions. Citrus and some other oils can make skin more sensitive to sunlight. Never swallow oils or put them in your eyes, ears, nose or other body openings, and store them where children cannot reach them.

Lavender and tea tree oils have estrogen-like effects. Long-term skin use has been linked to breast growth in young boys, and people with estrogen-sensitive cancers should be careful with repeated use. Check with your doctor first if you are pregnant, breastfeeding or trying to conceive, have epilepsy or seizures, asthma, or kidney or liver problems, or are having cancer treatment. Ask a therapist before using oils on children or on broken, sore or inflamed skin. Tell your doctor which oils you use, because they could affect other medicines, and do not use aromatherapy in place of prescribed treatment.

If you have symptoms that are new, severe or not improving, see a doctor or other licensed clinician rather than relying on aromatherapy alone.

How it fits with the pillars

For the body, aromatherapy reaches you through the skin, usually in massage, and through breathing.

For the mind, scent is closely tied to mood and memory. Many people use a familiar smell to wind down at the end of the day or to settle before sitting quietly. If that is what draws you, the site’s guide to meditation and essential oils covers using scent as part of a meditation routine.