Essential oils, otherwise known as volatile oils, are produced when special cells found in plants are crushed — releasing their unique fragrances. For thousands of years, fragrant-rich plants have been used as a means of healing through a process now known as aromatherapy. Like acupuncture and other traditional Chinese medicine, aromatherapy has recently become a popular supplement to traditional cancer care.

When administered by a professional, essential oils can be useful in helping with symptom management. Different oils can be used different ways — some can be ingested orally and some can be applied to the skin. You can also use direct inhalation through a nasal inhaler, or indirect inhalation with a diffuser, to fill your nose or room with a certain scent.

Certain plants are more effective than others in treating side effects of cancer. Some different oils for which patients have reported benefits include:

Arnica — A strong support for muscle tension and bruises.

Ginger — Effective in easing nausea.

Lavender — Has relaxing properties for adult patients, serves as a stimulant for pediatric patients, and decreases nausea.

Peppermint — Eases nasal congestion and nausea.

Still, as every patient is unique, you should consult an expert before using essential oils. Even when essential oils are natural, one can still be allergic to them through exposure, ingestion, inhalation, or through the skin. Some patients are also extremely sensitive to scents, especially when they are in chemotherapy.

Aromatherapy can help patients deal with this issue, as well as potentially helping ease smell, taste, and appetite-related challenges. Individuals in treatment, for instance, are often negatively impacted by the smell of cooking — especially animal proteins like chicken, beef, and fish. This can lead to a reduction in appetite and intake.

“Aromatherapy can introduce a soothing smell while you are near something cooking, and also possibly reduce the power of distressing smells,” says Dana-Farber nutritionist Stacy Kennedy, MPH, RD. “In terms of nausea, many patients experience benefits from cutting a lemon and smelling it before they eat, or including ginger or lemon in their food.”

Kennedy emphasizes that while it can be helpful to find new ways to reduce the side effects of cancer treatment, current research does not support aromatherapy as an effective treatment for cancer itself.

“There are a lot of options out there,” says Kennedy. “Use common sense and always ask your provider before starting a new regimen.”

This article was originally published on March 12, 2018, by Dana-Farber Cancer Institute. It is republished with permission.