Even though essential oils have been around for centuries, dating back to the early Egyptians and were brought as gifts to Jesus in biblical times (remember frankincense?), they've become more relevant today than ever before.

While people traditionally see a doctor for an illness and get a prescription drug, many others have awoken to the fact that essential oils can be used in healing and supporting the body's emotional and physical well-being.

These oils not only smell good, but they sometimes can heal at the cellular level. Essential oils are volatile liquids distilled from plants and parts such as seeds, flowers, fruit, stems, bark, roots and leaves. It may take hundreds of pounds of flowers and leaves to distill one batch of pure essential oil.

"Despite their name, essential oils are not oils but are aromatic, volatile substances or essences extracted from a plant, herb or flower by distillation or expression. It is a labor-intensive process resulting in a potent oil that is not cheap, but due to its concentrated nature, a small amount can be used very effectively for a range of ailments, skincare and even natural homemade carpet cleaner," says Ursula Elmes, an aromatherapist, licensed acupuncturist and the founder of YouOrganic Skincare.

"The most difficult part of using them is deciding on which oil will work most effectively with your own body chemistry, personal habits and emotional olfactory responses" says Tricia Mooneyham, host of the online radio show "I'll Have What She's Having…Talk with Tricia," who specializes in women's sexual health.

"There are certain oils which have proven their value and are a great baseline for those who are just learning about the health benefits of essential oils. Peppermint, lavender and lemon are considered power oils, and when in doubt one of these three will give you some relief for whatever your need is from cleansing to soothing to invigorating," says Mooneyham.

bottles of essential oilsAn aromatherapist can help you choose which essential oils might be best for you. (Photo: Kerdkanno/Shutterstock)

See an aromatherapist

Visiting a certified aromatherapist is similar to seeing a conventional doctor. Marci Cervone, a certified aromatherapist and owner of Thrive, a yoga, transformational coaching and aromatherapy practice in Jacksonville, Florida, has clients fill out an intake form, goes over their health history to check for contraindications such as epilepsy or high blood pressure, and discusses their needs. Cervone then selects oils that she feels would be helpful and makes sure that her clients like the scents; people who have an aversion to a smell usually won't want to use that oil.

Cervone then creates a blend of up to five oils for the purpose intended: relaxation, stress, eczema, a respiratory problem or other issues, and decides on the application preference such as an inhaler, bath oil, spray or skin tincture.

For people who are going to buy oils and experiment on their own, Cervone advises purchasing quality oils from companies that are GC/MS (gas chromatography-mass spectrometry) tested. This chemical test gives the breakdown of ingredients in a batch of oil. Some less ethical companies produce "oils" that may be only 20% pure oil and 80% filler. Cervone recommends avoiding companies and products that cannot produce a GC/MS report.

Within lavender oil, for instance, there will be dozens of chemical ingredients, and people need to know how powerful the ingredients are and what they are before using them on the skin, inhaling them, or taking them internally.

"It's one thing to put a few drops of oil on potpourri in a diffuser; it's another to inhale them or use them on your skin when you have no idea what you're getting," Cervone says.

A few common essential oils and their uses

Lavender is a calming oil that is said to help with panic attacks and to calm the nervous system. It is used on minor burns to soothe skin. It is commonly sprayed on pillows or linens, or applied to the neck, chest or temples to help wind down before sleeping.

Peppermint wakens the senses and can increase the oxygen level in the blood just by being inhaled. "One drop of peppermint oil is equivalent to 28 cups of herbal tea," Mooneyham says. It helps with focus, and when combined with rosemary, which helps with memory and retention, makes a winning work day combination. Peppermint also is used to calm a troubled tummy and to try to bring down fever.

lemon essential oil and lemon fruitLemon essential oil has bacterial properties and can treat minor injuries. (Photo: AmyLv/Shutterstock)

Lemon is used as an alternative treatment to remove corns and warts. It's a bactericide and is sometimes used to treat minor cuts and wounds as well. It is said to brighten dull skin, help with immunity and is used in antibacterial cleansers.

Frankincense, used in biblical times, is the king of all oils. This oil is used to aid other oils to work at deeper levels to provide more healing. Frankincense has been studied for its ability to kill cancer cells. Some use it to combat skin inflammation and rashes, and others say it brings about focus and clarity.

cinnamon leaf oilMade from the leaf of the cinnamon bush, this oil is great for keeping skin and hair healthy. (Photo: Liljam/Shutterstock)

Cinnamon leaf can be mixed with cinnamon sugar, orange juice and olive oil for an antiseptic facial scrub. It can be used as part of a foot soak to fight nail and foot fungus and as a shampoo to keep hair healthy.

Grapefruit, another citrus oil, has similar properties as lemon. It can help uplift your mood and might work as a mild antiseptic.

Tea tree is lauded for its healing properties. It may be effective against acne, dandruff and fungal nail infections. That's why tea tree oil is found in so many skincare products. Some people even find success taking a drop or two for a sore throat.

eucalyptus essential oilEucalyptus oil smells so fresh and clean. That's probably why it helps with congestion. (Photo: JPC-PROD/Shutterstock)

Eucalyptus has many antibacterial properties. Its distinctive smell might help with breathing and congestion, particularly with stuffiness associated with colds and allergies. You can put some in a vaporizer when you're congested.

Most of these oils have multiple benefits in a single oil, though their potency is a hard concept for many people to grasp. The National Association for Holistic Aromatherapy has a wealth of information and a large database.

"I think of essential oils like food," Cervone says. "You don't just eat once, and never again; it's an ongoing process to get good nutrition and support your body's needs. Same with essential oils — you can literally use them to support your body's health and well-being from the moment you wake up in the morning to the moment your head hits the pillow."

Staying safe with essential oils

Never swallow essential oils. Many of the oils can be dangerous if taken internally, reports WebMD. Don't use oils close to your eyes or mouth. They can cause irritation to skin and delicate membranes.

Never use essential oils with children under 5, who can be very sensitive to the oils. In addition, be sure to keep essential oils out of the reach of children. Recent reports from poison centers in the U.S. and Australia have found that essential oils are accidentally poisoning more and more kids.

If you have certain medical conditions, it may not be safe to use essential oils. For example:

  • Oils may cause spasms for people with lung conditions such as asthma, allergies or chronic lung disease.
  • People with skin allergies may have skin irritation due to the oils, especially around the eyes, nose and mouth.
  • Pregnant women shouldn't use essential oils. Some oils may cause uterine contractions.

Talk to your doctor about how you want to use essential oils and, if you decide to use them, include them in your medical history, just as you would with supplements.

Editor's note: This story has been updated with new information since it was published in September 2015.

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