The Research Behind Calming Essential Oils for Anxiety, Stress, and Sleep

Essential oil aromatherapy has been used traditionally around the world for centuries to boost mood and stress resilience, but what about scientific research into their effectiveness? 

While large-scale clinical trials are still limited, a growing body of research over the past decade has examined the effects of specific essential oils on anxiety, stress, and related outcomes.

In this post, I summarize representative human and animal studies for each of the calming essential oils I recommend in my 9 Best Calming Essential Oils for Anxiety, Stress and Sleep post, with brief explanations of how anxiety and stress are measured in research settings.

While most of the research I refer to focuses on the oil's anti-anxiety qualities, interventions that reduce stress and anxiety have the potential of improving sleep for anyone who has difficulty relaxing for sleep or is kept awake by an anxious spinning mind.

How Anxiety and Stress Interventions Are Studied in Research

I became familiar with many of the research methods used to evaluate natural anxiety remedies while researching and writing my book Feed Your Calm: Anti-Anxiety Anti-Stress Diet and Supplement Tips for Stress Resilience. My first career as a medical lab technologist in hospital microbiology labs really came in handy when reading and evaluating study results. 

Because research methods vary widely — and assessing the validity of natural remedy studies is particularly important — it can be useful to understand how anxiety and stress interventions are studied before looking at individual findings. This context can help you better assess the relevance and usefulness of the studies summarized throughout this post.

Different Research Methods 

Clinical populations: Some anxiety studies are performed on groups of people diagnosed with anxiety disorders.

Inherently stressful situations: Other studies involve groups living through stressful circumstances such being in labor or pre-surgery, or patients with severe distress because of their medical conditions. 

Short-term experimental stress: Sometimes researchers put subjects, such as university students, into short-term anxiety-provoking situations so they can study the impact of anti-anxiety interventions. Research protocols are tested and standardized. 

The Stroop Color-Word Test (SCWT)

One commonly used method for inducing short-term anxiety in healthy participants is the Stroop Color-Word Test (SCWT):

• While being videotaped and believing that they are being observed and evaluated by “professionals” in another room, study participants have to name as quickly as possible (with a two-minute maximum) colors presented to them. 
• The trick is that they have to name the color of ink used to print the color name, and it is different than the color name (e.g., BLUE printed with pink ink has to be named as “pink”).
• To add to the stress, if they hesitate or make an error, a bell rings.

Let's look at two essential oil research projects using the SCWT and then others using a variety of human subject groups. 

Lemongrass Essential Oil SCWT: Increased Resilience

An interesting 2015 Brazilian study examined the impact of lemongrass aroma on men at three times: (1) after initial exposure to the scent, (2) during a stress-inducing SCWT "test", and (3) after the "test." 

• Forty men were divided into groups. The men inhaled lemongrass essential oil from a tissue for three deep breaths and then the scent was immediately removed. The lemongrass group experienced a drop in anxiety markers compared to groups exposed to either tea tree oil or water. All the participants were then put through the Stroop Color-Word Test (SCWT).

• The quick exposure to lemongrass aroma prior to the SCWT did not reduce the anxiety of the participants compared to the control groups during the SCWT, but within five minutes after the tricky color-naming test, anxiety levels in the lemongrass group returned to their baseline while the other groups’ anxiety remained elevated.

To recap: The lemongrass scent immediately reduced anxiety. While it didn't impact anxiety during the stress-test, it did help the subjects' stress-resilience in that they recouped from the stressful event faster than people not exposed to the scent. 

Sweet Orange Essential Oil SCWT: Reduced Anxiety and Stress

The Stroop Color-Word Test (SCWT) was similarly used to test the effectiveness of sweet orange (Citrus sinensis) essential oil. In the 2012 sweet orange aromatherapy study, the subjects exposed to the essential oil scent had less anxiety and tension during and after the SCWT than the control group. 

Lavender Oil Benefits Research: Reduced Anxiety, Stress, and Depression Post-Partum

In a 2016 study testing the impact of lavender essential oil after childbirth:

• 140 post-partum women were divided into an aromatherapy group and a control non-aromatherapy control group.
• The aromatherapy group inhaled from 3 drops of lavender essential oil every 8 hours for 4 weeks.
• All the women were assessed for stress, anxiety, and depression using standardized tests at 2 weeks, 1 month, and 3 months post-partum.

The results showed that stress, anxiety, and depression were all lower in the aromatherapy group compared to the control group each time the tests were done. 

Notably, the positive effect went on beyond the period of time that they were instructed to use the essential oil. 

Lavender and Rose Oil Benefits: Aromatherapy Reduced Pain and Anxiety in Burn Patients

This 2016 lavender and rose aromatherapy study is a good example of the proof of essential oil's anti-anxiety benefits.

90 burn patients were divided into three groups:

1. Aromatherapy massage with oil that included lavender essential oil 

2. Inhalation aromatherapy using a blend of lavender and rose oils

3. Control group that was given neither of the above

The researchers' conclusions:

"The study results showed the positive effect of aromatherapy massage and inhalation aromatherapy compared with the control group in reducing both anxiety and pain of burn patients. Therefore, both interventions, which are inexpensive, and noninvasive nursing tasks can be proposed for alleviating anxiety and pain of burn patients."

Rose Essential Oil Studies: Anxiety, Pain, Depression, and PMS Relief

Use of rose oil and water is common in Iran, so they have studied its effectiveness extensively. 

• Researchers in Iran (2017) reviewed 13 studies on Rosa centifolia and Rosa damascena. They reported that rose oil and anti-depressant, pain relieving, psychological relaxation, and anti-anxiety effects. 
• A 2016 study of 40 dialysis patients showed that rose water inhalation reduced anxiety. 
• A 2019 study of 95 premenstrual women showed significant improvement of psychological, physical, and social aspects of premenstrual syndrome symptoms when they inhaled rose oil for 5 minutes while relaxing twice a day on each of 5 days prior to menstruation. 

Bergamot Aromatherapy: Reduced Pre-Surgery Anxiety 

Research on 109 pre-op patients in Taiwan (2013): Patients exposed to bergamot aromatherapy via a diffuser hidden behind a curtain showed a greater reduction in preoperative anxiety than those in the study's control groups. 

Neroli Essential Oil Diffusion: Reduced Anxiety and Pain During Labor

A 2022 Italian study of 88 women during labor showed significantly lower perceived pain and anxiety in the group receiving neroli aromatherapy (diffused continuously through a diffuser using four drops of aroma oil per 300 mL of diffused water) than in the control group at all stages of labor.

Geranium Essential Oil Diffusion: Reduced Anxiety and Blood Pressure During Labor

Geranium essential oil was diffused in the labor rooms of 50 Iranian women while another 50 women in the control group did not receive this intervention. 

This 2015 study showed a significant reduction in anxiety and diastolic blood pressure in the aromatherapy group. 

Lemon Balm Inhalation: Anxiety and Multiple Physical Symptom Improvements 

Sixty-eight hemodialysis patients were randomly divided into two groups in a 2025 study:

•  Lemon Balm (Melissa officinalis) group: underwent essential oil inhalation aromatherapy 3 times a week for one month during hemodialysis sessions
•  Control group: inhaled refined sweet almond oil on a similar schedule

Anxiety inventory questionnaires were completed before and after the intervention. 

A lot of positive changes were observed in the Lemon Balm group:

"Before the intervention, both groups were similar in terms of anxiety and symptoms burden. However, after the intervention, a significant difference was found between the groups in terms of state and trait anxiety, and severity of constipation, nausea, vomit, diarrhea, swelling in legs, muscle cramps and shortness, worry, nervousness and anxiety, and trouble staying asleep. Moreover, after the intervention, a significant difference was observed between the groups regarding the prevalence of symptoms burden such as feeling anxious and having a dry mouth."

Ylang Ylang Inhalation: Improved Serotonin and Cortisol Levels Post-Stressor in Mice

Not all medicinal studies are performed on humans. Animal studies are also often used. A few different protocols have been designed and standardized for testing levels of anxiety in mice in different conditions. 

The Elevated Plus Maze (EPM) Test

The Elevated Plus Maze (EPM) test is widely used to assess the anxiety-relieving effects of pharmaceutical medications as well as natural remedies including supplements and essential oils, because it produces consistent, measurable behavioral outcomes. 

The test involves a structure with two open arms and two enclosed arms arranged in a plus sign shape and elevated above the floor. 

Rodents naturally avoid the open arms due to fear of exposure and height, while exploratory behavior draws them toward novelty. Increased time spent in the open arms is interpreted as reduced anxiety-like behavior. 

University professors in Shanghai, China (2018) used the EPM to test anxiety levels in mice after exposure to Ylang Ylang (Cananga odorata) fragrance. Compared to a control group, stressed mice exposed to Ylang Ylang aroma spent more time in the open arms--indicating reduced anxiety. 

They also performed bio-chemical analysis on the mice. Their results found increases in the feel-good neurotransmitter serotonin and reduced cortisol levels in the Ylang Ylang group. 

The improvements seen in these experiments suggest that aromatherapy with Ylang Ylang can help with both depression and anxiety.

Additional Support for Anxiety Relief and Stress Resilience

Aromatherapy and essential oils can be one layer in a broader approach to wellbeing, but many people benefit from multiple tools and skills that reduce stress load and build resilience. 

Through years of counseling people experiencing chronic stress and anxiety — and my own experiences overcoming anxiety rooted in childhood — I’ve developed practical, user-friendly resources to make your life better.

Whether you’re just beginning your wellness journey or looking for additional tools to supplement what you’re already doing, these resources are meant to meet you where you are ease you forward. 🟢➜ Click on the graphic below to find the best fit for your next step. 

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