How and why to use essential oils

Essential oils in clear bottles with flowers on the background

Aromatherapy, or the use of essential oils, dates back thousands of years, when the ancient Egyptians first burned incense made from aromatic woods, herbs and spices. Today, the practice has evolved into a $12 billion global business.

“Essential oils are a fantastic way to help with myriad issues such as sleeplessness, nausea, anxiety, allergies and pain,” says Michele Mack, LMT, CPMT, a licensed massage therapist at Ohio State Integrative Medicine.

Despite a surge in popularity, essential oils are not regulated by the FDA, and not all are created equal. This may have some wondering: How do essential oils work? How do you use them? And are there risks?

How do essential oils work?

Essential oils are an umbrella term used to describe highly concentrated, steam-distilled or cold-pressed extracts of almost any part of a plant, such as seeds, flowers, fruit, leaves, stems and roots, that are said to improve physical and psychological well-being.

To this day, neither the government nor the FDA have widely studied or regulated essential oils, so their effects have yet to be supported by scientific research. However, millions of people turn to aromatherapy every day, swearing by its ability to treat common health ailments like anxiety, congestion and joint pain.

According to Mack, essential oils have psychological (affecting emotion), pharmacological (affecting chemistry) and physiological (affecting bodily function and process) benefits. The most common ways to use essential oils are by breathing them in (inhalation) and by applying them to the skin(topical). Swallowing them is an option, but Mack says ingestion should only occur under direct supervision of a doctor or certified aromatherapist.

Those who use essential oils topically tend to do so for cosmetic purposes or to treat pain. Oils are absorbed via the epidermis (top layer of skin), move from the soft tissue to the bloodstream, are carried to the treatment areas and then metabolized in the liver.

Most essential oil users inhale them to experience their psychological effects, such as stress relief. When inhaled, the molecules are distributed into the respiratory system, but a small amount has been shown to affect our brain.

“When it is routed to our brain, we identify the smell and, in some cases, we have an emotional response to that smell,” Mack says. “In animal studies, it has been shown that inhalation has a quicker effect of distributing the sedative properties of certain oils in the body.”

Mack adds that psychological reactions to essential oils tend to be subjective, as scents can mean different things to different people. 

“The area where I grew up had an abundance of pine trees and citrus groves. So, for me, the smell of citrus and pine triggers a deep emotional response that both calms and revitalizes me, and these are often the oils I turn to in times of stress,” she explains. “However, someone who grew up in other parts of the world may not have the same psychological response to these scents, as they may mean nothing to them.”

While the effects of certain oils are tied to a person’s history, Mack says there are some trends for which oils are most beneficial for different goals.

What are common kinds of essential oils and their uses?

  • Bergamot: skin healing and anxiety-reducing
  • Chamomile: cold, fevers and nausea 
  • Clove: dental and pain-relieving
  • Eucalyptus: topical pain-reliever and decongestant
  • Frankincense: mood-enhancer and stress-reducer
  • Lavender: calming and sleep-inducing
  • Lemon: a natural household cleaner and disinfectant 
  • Oregano: skin-healing
  • Peppermint: cold and flu prevention and energy-booster
  • Rosemary: skin and hair health and joint pain

When shopping for essential oils, Mack cautions that not all brands are created equal. Many mass-marked oils (i.e. sold in grocery stores or big-box retailers) include a combination of lesser and/or synthetic oils.

Mack adds that it is important to research the botanical name, batch number and the corresponding GC/MS (purity) report before purchasing a specific brand of essential oil.

How do you use essential oils?

Mack advises that the safest ways to use oils are to dilute them for topical use or diffuse them for direct inhalation. When using topically, Mack says essential oils should always be applied with a barrier substance (like an oil, lotion or aloe jelly). If using in a bath, it is even more important to mix the oils with a barrier substance first, as oil and water don’t mix. 

Mack also dispels the notion that applying essential oils to the bottom of the feet is the best way to absorb the properties. She says applying oils to the tops of feet, arms, wrists, neck and behind the ear generally produce better and more consistent results for most people. 

For those inhaling essential oils, Mack recommends using a waterless or water-based diffuser. Waterless diffusers are great for those with respiratory issues or immunocompromised states, as the deletion of water reduces the risk of waterborne bacteria being distributed.

Can you use essential oils in place of prescription medication? Does insurance cover it?

“Using essential oils should never be used in place of any medication without proper supervision by a physician. However, they can be used to complement your current medication regime,” Mack says.

And because essential oils are not recognized as a medication or essential to medical well-being, they are not covered by insurance, Mack adds.

Are essential oils safe?

For the most part, if used correctly, essential oils are safe. Even poor-quality oils are safe to use, although they may be less effective. 

However, essential oils do carry some risks, which Mack says can be avoided by following these steps:

  1. If ingesting essential oils, only do so under the direct supervision of a doctor or certified aromatherapist.
  2. If using oils topically, first test them out by mixing a few drops with a carrier substance (like coconut oil), applying to a small area and watching for a skin reaction. Some essential oils, like bergamot, can cause skin sensitivity when in direct sunlight. Be aware of possible side effects.
  3. Exercise caution when using essential oils around children, as many oils are not considered safe for children under the age of 5. Some oils can cause physical and respiratory distress in still-developing bodies.
  4. Never apply oils directly to an animal, and always ask a veterinarian before using essential oils around a pet.
  5. Consult a certified aromatherapist to discover the oils that work best for you and to determine their safety and side effects.

“Essential oils and aromatherapy are highly individualized and can affect everyone differently,” Mack explains. “Know that if there is a single oil that is not appropriate for you, there are several more that can be used with the same benefits.”

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