Essential Oils 101: Do They Work + How Do You Use Them?

An integrative medicine specialist shares which oils to use and avoid
essentail oils and how to use them

Alternative medicine enthusiasts have subscribed to the power of essential oils for years. But with their increasing availability (and claimed health benefits), they’re going mainstream.

Advertising Policy

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

“Essential oils are fantastic. They have many benefits,” says integrative medicine specialist Yufang Lin, MD. “The problem lies in how people use them.”

What are essential oils?

Essential oils are concentrated plant extracts. “Plants are made of structural materials and phytochemicals. These chemicals have properties that not only benefit the plant but benefit people, too,” explains Dr. Lin.

It takes a tremendous amount of plant material to make essential oils. For example:

  • About 250 pounds of lavender flower make 1 pound of lavender essential oil.
  • About 5,000 pounds of rose petals or lemon balm make 1 pound of rose or lemon balm essential oil.

“Because it takes so much of the plant to make an essential oil, it’s a powerful botanical medicine,” she says.

How to use essential oils

Because essential oils are so strong, Dr. Lin recommends being mindful about why and how you’re using them. Only small doses are required. “It’s also a good idea not to use them routinely, as your body can get used to them, lowering their effectiveness,” she says.

There are three ways you can use essential oils:

1. Aromatherapy

Aromatherapy involves smelling essential oils to improve health. “It’s a great way to change your mood quickly. As you breathe in, the oil’s aroma immediately stimulates your central nervous system, triggering an emotional response,” explains Dr. Lin. “It can reduce anxiety and stress response quickly.”

There are several aromatherapy methods. “Whichever method you choose, avoid direct contact with the essential oil and dilute it first,” says Dr. Lin.

Aromatherapy methods include:

  • The old-fashioned way: Take deep breaths of the aroma after opening the bottle.
  • Diffuser method: Mix essential oils and water in an essential oil diffuser and turn on the magic. A diffuser is a device that disperses tiny oil particles around the room so you can breathe them in. Follow your diffuser’s directions for the right oil-to-water ratio.
  • Dry evaporation: Put a few drops of essential oil on a cotton ball and smell the aroma as it disperses.
  • Steam inhalation: Put a few drops of essential oil in a bowl of hot water. Put your head over the bowl, a towel over your head and breathe in the steam.

One caveat is that aromatherapy may not work as well for older adults with dementia or behavior problems, she notes. That may be because people tend to experience loss of smell as they get older.

Advertising Policy

2. Ingestion

Some people take essential oils orally in teas, supplements or even via a drop or two on their tongue. “Unless you’re directed by a trained herbalist, I recommend against using them this way. Since they’re so strong, they may be harmful,” advises Dr. Lin. “Even with just a few drops of essential oil, you’re taking a lot of plant material without realizing it. They can even burn the mucosal lining in your mouth.”

3. Topical application

You can also reap the benefits by applying essential oils to your skin, where it’s absorbed into your body. But Dr. Lin cautions against directly applying essential oils to your skin without diluting them. “With few exceptions, it’s best to dilute the essential oil with a carrier oil, such as coconut or jojoba oil, to avoid skin irritation,” she says.

Some people put their essential oil blend into a small rollerball bottle for easier application.

Health benefits of essential oils

Studies have shown that essential oils may:

Common essential oils and their uses

Lavender oil

Lavender is Dr. Lin’s go-to oil. “It’s gentle and has a lot of benefits. You can also use it in a variety of ways,” she says.

Lavender can help with stress, pain and sleep. “Before they discovered antiseptics, lavender was also used as a cleaning agent in hospitals,” Dr. Lin says.

Tea tree oil

Dr. Lin says most people use tea tree oil as an antiseptic, antimicrobial or antifungal. You can also use it to help:

  • Acne: “Take a cotton swab and dip it into tea tree essential oil. Then apply it directly on the acne — this is one exception where you don’t have to dilute it,” says Dr. Lin. “It can help resolve acne faster.”
  • Athlete’s foot and ringworms: “Dilute it with a carrier oil and put the blend on the affected skin.”

One note of caution: Since tea tree oil can be neurotoxic, Dr. Lin says you shouldn’t diffuse it if you have small children or animals at home.

Frankincense oil

Known as the “king of oils,” frankincense can help with inflammation, mood and sleep.

Peppermint oil

Peppermint oil is known to:

Advertising Policy

“Peppermint tea can settle your stomach, too if you have irritable bowel syndrome or gastric irritation,” adds Dr. Lin. “It’s very gentle and easy to use.”

Eucalyptus oil

Eucalyptus is a great essential oil to have on hand during cold season. It soothes a stuffed-up nose by opening your nasal passages so you can breathe easier. (Peppermint oil can also help with this.)

Essential oil use in children, pregnant women and older adults

Be careful when using essential oils in children, people with weakened immune systems, pregnant women and seniors. “Some essential oils can be harmful to the liver and nervous system when used in excess. Tea tree and eucalyptus oil have also been known to cause seizures,” warns Dr. Lin. “They’re toxic for animals as well.”

If you are pregnant, these oils tend to be safe for use if you properly dilute them:

  • Chamomile.
  • Frankincense.
  • Geranium.
  • Lavender.
  • Neroli.
  • Rose.
  • Sandalwood.
  • Spearmint.
  • Ylang ylang.

“Citrus oils — lemon, orange, lime, tangerine, grapefruit and bergamot — are also safe, but they cause photosensitivity to light when applied to the skin,” Dr. Lin says. “If you’re not careful, that could lead to a quick sunburn.”

Essential oils you should avoid

Potentially toxic oils include:

  • Bitter almond.
  • Inula.
  • Khella.
  • Mugwort.
  • Pennyroyal.
  • Sage.
  • Sassafras.
  • Thuja.
  • Turmeric.
  • Wintergreen. 

Dr. Lin also says to make a note of these very toxic oils:

  • Ajowan.
  • Arnica.
  • Boldo.
  • Calamus.
  • Cascarilla.
  • Chervil.
  • Camphor.
  • Deer tongue.
  • Horse radish.
  • Jaborandi.
  • Mustard.
  • Narcissus.
  • Nutmeg.
  • Parsley.
  • Rue.
  • Santolina.
  • Spanish broom.
  • Tansy.
  • Tonka.
  • Wormseed.
  • Wormwood.

How to buy essential oils

The essential oil business is booming — and mostly unregulated. That’s why Dr. Lin says it’s important to make sure you’re getting the real deal and not some chemical-laden snake oil. “Go for organic, minimally processed essential oils,” she recommends. “You can find good quality oils at natural and organic grocery store chains and health stores.”

Look for oils that are:

  • 100% pure: Choose oils that don’t have any added ingredients or synthetic oils. (And just say no to “fragrance oils.”)
  • Sold in dark glass bottles: These bottles protect the oil’s quality since light and plastic can damage them. Reputable sellers typically package essential oils in bottles that hold 4 ounces or less.
  • Labeled with details about the oil’s source: Choose manufacturers that:
    • Use the plant’s botanical, or Latin, name. For example, peppermint oil would also list Mentha piperita on the label.
    • Specify the part of the plant used to make it (for example, the leaf).
    • Extract oils through distillation or mechanical cold pressing.
    • Sell organically grown oils.

Advertising Policy