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.

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

Here’s information on 11 essential oils, their benefits and how best to 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, which can make some of them expensive. 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,” Dr. Lin says.

Benefits of essential oils

Essential oils can be used in aromatherapy, a kind of complementary medicine that uses smell to improve your health or applied topically to the skin.

Studies have shown that essential oils may help:

Boost mood.

Improve job performance through reduced stress and increased attentiveness.

Improve sleep.

Kill bacteria, funguses and viruses.

Reduce anxiety and pain.

Reduce inflammation.

Reduce nausea.

Relieve headaches.

Here are some common essential oils and their benefits:

Lavender oil

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

Try adding it to a bath or diffuser as aromatherapy, adding to water to make a room spray or body spritzer, or combining with a base oil to make body oil.

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

There have also been studies that show using lavender oil (and tea tree oil) can potentially disrupt hormones in young boys.

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 with:

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 (a base or vegetable oil like coconut or jojoba oil that helps dilute essential oils) 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.

What Are Essential Oils, and Do They Work?

Essential oils are often used in aromatherapy, a form of alternative medicine that employs plant extracts to support health and well-being.