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Bergamot ( Citrus bergamia ) Essential Oil Inhalation Improves Positive Feelings in the Waiting Room of a Mental Health Treatment Center: A Pilot Study: Essential Oil Inhalation Improves Positive Feelings


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Mental health issues have been increasingly recognized as public health problems globally. Their burden is projected to increase over the next several decades. Additional therapies for mental problems are in urgent need worldwide due to the limitations and costs of existing healthcare approaches. Essential oil aromatherapy can provide a cost-effective and safe treatment for many mental problems. This pilot study observed the effects of bergamot essential oil inhalation on mental health and well-being, as measured by the Positive and Negative Affect Scale, in a mental-health treatment center located in Utah, USA. Fifty-seven eligible participants (50 women, age range: 23–70 years) were included for analysis. Fifteen minutes of bergamot essential oil exposure improved participants' positive feelings compared with the control group (17% higher). Unexpectedly, more participants participated in experimental periods rather than control periods, suggesting even brief exposure to essential oil aroma may make people more willing to enroll in clinical trials. This study provides preliminary evidence of the efficacy and safety of bergamot essential oil inhalation on mental well-being in a mental health treatment center, suggesting that bergamot essential oil aromatherapy can be an effective adjunct treatment to improve individuals' mental health and well-being. © 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.
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Bergamot (Citrus bergamia) Essential Oil
Inhalation Improves Positive Feelings in the
Waiting Room of a Mental Health Treatment
Center: A Pilot Study
Xuesheng Han,
*Jacob Gibson,
Dennis L. Eggett
and Tory L. Parker
dōTERRA International, LLC, 389 South 1300 West, Pleasant Grove, UT 84062, USA
The Green House Center for Growth and Learning, 135 West Center Street, Pleasant Grove, UT 84062, USA
223 TMCB Brigham Young University, Provo, UT 84602, USA
Mental health issues have been increasingly recognized as public health problems globally. Their burden is
projected to increase over the next several decades. Additional therapies for mental problems are in urgent need
worldwide due to the limitations and costs of existing healthcare approaches. Essential oil aromatherapy can
provide a cost-effective and safe treatment for many mental problems. This pilot study observed the effects of
bergamot essential oil inhalation on mental health and well-being, as measured by the Positive and Negative
Affect Scale, in a mental-health treatment center located in Utah, USA. Fifty-seven eligible participants
(50 women, age range: 2370 years) were included for analysis. Fifteen minutes of bergamot essential oil
exposure improved participantspositive feelings compared with the control group (17% higher). Unexpectedly,
more participants participated in experimental periods rather than control periods, suggesting even brief
exposure to essential oil aroma may make people more willing to enroll in clinical trials. This study provides
preliminary evidence of the efficacy and safety of bergamot essential oil inhalation on mental well-being in a
mental health treatment center, suggesting that bergamot essential oil aromatherapy can be an effective adjunct
treatment to improve individualsmental health and well-being. © 2017 The Authors. Phytotherapy Research
published by John Wiley & Sons Ltd.
Keywords: bergamot essential oil; aromatherapy; mental well-being; mental health; positive affect; negative affect.
Mental health disorders have been increasingly
recognized as public health problems globally (Kessler
et al., 2015). Mental health disorders include abnormally
high levels of anxiety, depression, stress, cognitive
impairment, insomnia, and so on. Of note, the prevalence
of stress-related symptoms among the working class has
been increasing across a wide variety of occupations
(Baba et al., 1999; Johnson et al., 2005; McCarthy et al.,
2016). The health impact of mental disorders is both
immediate and long term. The immediate health effects
relate to overall well-being, quality of life, work
performance, and social interactions (McCarthy et al.,
2016). Long-term health effects can lead to chronic
diseases and premature death (Andrews and Carter,
2001). A recent World Health Organization (WHO)
World Mental Health survey (N= 52 095) (Bruffaerts
et al., 2015) found a consistent association between pre-
existing mood (odds ratio = 1.31.4), anxiety (odds
ratio = 1.21.7), and the subsequent onset of headaches.
The WHO Global Burden of Disease Study (Bruffaerts
et al., 2015) estimates that mental disorders are among
the most burdensome in the world, and their burden will
increase over the next 4 decades. The current healthcare
system has inadequately addressed individuals with
mental disorders. This includes a lack of good
operational propositions, lack of professionalism, low
quality of care, and improper pharmaceutical
prescriptions (Mercier et al., 2010). Almost all prescribed
drugs for mental disorders come with a long list of side
effects (Jones and Lal, 1985; Bantz et al., 1987; Etzel,
1994; Gerlach and Larsen, 1999; Schaefer et al., 2003;
Rummel-Kluge et al., 2010). Alternative therapies for
mental disorders are in urgent need worldwide.
The inhalation of essential oils may provide a cost-
effective, safe, and appropriate therapy for some mental
disorders. Many human studies involving a wide
diversity of patients and healthy volunteers have
successfully shown significant positive effects of
lavender essential oil (Moss et al., 2003; Toda and
Morimoto, 2008; Hongratanaworakit, 2011; Seifi et al.,
2014) on stress relief, anxiety reduction, mood
improvement, and depression relief. Chemical analysis
of lavender essential oil shows a complex mixture of
naturally occurring phytochemicals, including linalool
and linalyl acetate (Prashar et al., 2004). It has been
suggested that the major components in essential oils
contributing to anti-anxiety and anti-depressant effects
are linalool (Linck et al., 2010), limonene (Lima et al.,
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium,
provided the original work is properly cited.
* Correspondence to: Xuesheng Han, dōTERRA International, LLC, 389
South 1300 West, Pleasant Grove, UT 84062, USA.
Contract/grant sponsor: dōTERRA International, LLC.
[Correction added on 06 April 2017, after first online publication: Contract/
grant sponsor has been corrected in this version].
Phytother. Res. 31: 812816 (2017)
Published online 24 March 2017 in Wiley Online Library
( DOI: 10.1002/ptr.5806
© 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.
Received 28 November 2016
Revised 19 January 2017
Accepted 27 February 2017
2013), and pinene (Satou et al., 2013). Reasonably, it has
been proposed that essential oils with a high content of
these compounds could have anxiolytic and anti-
depressant effects as well.
Bergamot essential oil (hereafter BEO) has a long
industrial and medicinal history (Navarra et al., 2015).
It is characterized by a high content of limonene,
linalool, and linalyl acetate. Several clinical studies on
aromatherapy with BEO, in combination with other
essential oils, have shown promising results: anxiety
and stress reduction, anti-depression, pain relief, and
blood pressure and heart rate reduction. Further human
studies with BEO inhalation alone have also shown
significant effects on anxiety reduction (Watanabe
et al., 2015), depression reduction (Watanabe et al.,
2015), and blood pressure (Chang and Shen, 2011; Ni
et al., 2013) and heart rate reduction (Chang and Shen,
2011; Ni et al., 2013). In addition, BEO has minimal side
effects, if any (Navarra et al., 2015), suggesting BEO
inhalation may have potential therapeutic benefits
including improving overall mental health and anxiety.
We explored the effect of BEO inhalation on
participantsmental well-being and feelings in the lobby
of a mental health treatment center prior to receiving
treatment. Participantsmental health was measured by
a self-rated questionnaire: The Positive and Negative
Affect Schedule (PANAS), a standardized, well-validated
outcome measurement (Watson et al., 1988). PANAS has
been shown to be an effective measurement for
momentary mental health and well-being, incorporating
both positive and negative dimensions of mood (Watson
et al., 1988; Crawford and Henry, 2004). It has also been
widely used to evaluate individualsmood states in a
variety of situations (Crawford and Henry, 2004).
This study was conducted in the waiting room of a
mental health treatment center (The Green House
Center for Growth and Learning, Pleasant Grove,
UT, USA). Participants were current patients of the
center or patientscompanions. This study was
reviewed and approved by an institutional review
board (IRB) before commencement.
Inclusion and exclusion criteria. Both women and men,
aged between 18 and 70 years, were included if they
could communicate verbally and read and write in
English. Women who were pregnant and/or lactating
were excluded. People with no sense of smell or with
known pre-existing sensitivities to essential oils were
excluded from the study. Patients who, judged by the
staff of the treatment center as not good candidates for
the study, were also excluded.
Procedure. The trial lasted 8 weeks. Weeks 1, 3, 5, and 7
were essential-oil diffusion periods; weeks 2, 4, 6, and 8
were distilled-water diffusion periods. Participants who
met the above eligibility criteria and agreed to
participate were instructed to sit as still as possible in
the waiting room for 15 min. Written consent was
waived per an IRBs evaluation. Depending on the
week they came to the center, they were exposed to
either bergamot or distilled water aromatically. Patients
were told the study was intended to assess the waiting
times effect on mental feelings to distract their
attention from the smell in the waiting room. After
15 min, participants were asked to complete the PANAS
survey and demographic information (Fig. S1). Then,
they could proceed with their regularly scheduled
treatment. Any adverse events were also recorded.
Study instruments and materials. The aromatherapy
devices were four waterless diffusers, provided by
dōTERRA (Pleasant Grove, UT, USA), and placed out
of sight of the participants in the waiting room. The gas
chromatographymass spectrometry analysis of BEO
showed that its major chemical constituents (i.e., >5%)
are limonene (36%), linalyl acetate (31%), linalool
(11%), gamma-terpinene (8%), and beta-pinene (7%).
The diffusers were turned on 15 min before the first
patient arrived and kept running at half speed throughout
the day. The speed setup of diffusers and their locations
were selected based on previous experiments
(unpublished data), ensuring that a comfortable and
consistent aroma was maintained through the day. Facility
staff routinely checked each diffuser to ensure there was
always sufficient essential oil or distilled water, and
replaced new bottles of oil or water if needed. This
ensured that each participant received an equivalent
strength and amount of oil aroma or water vapor during
the 15-min study period, which approximately mimicked
the real-life scenario of aromatic usage of essential oils.
The PANAS has been extensively validated and
utilized to assess momentary mental well-being (Watson
et al., 1988; Crawford and Henry, 2004). It consists of 20
items (e.g. interestedand distressed), and respondents
rate the intensity of their feelings about each item at that
moment from 1 (very slightly or not at all)to5(extremely).
Ten items assess respondentspositive feelings, while the
other ten assess negative feelings. Scores range from 10
to 50 for either positive or negative affect. The PANAS
typically takes less than 5 min to complete.
Statistical analysis. Fifty-nine participants completed the
study. Two were missing scores for one or more of the
PANAS items; therefore, they were excluded from
analysis. The age range was 2358 years for the BEO
group, and 2370 years for the control group (Table 1).
Most participants (50 out of 57) were female and
Table 1. Participants demographic information
Active group (n) Control group (n)
Participants 45 12
Women 38 12
Men 7 0
Womens age range (years) 2358 2370
Mens age range (years) 3648 n/a
Caucasian 41 12
Non-Caucasian 4 0
Female and Caucasian 36 12
Patients 10 0
© 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd. Phytother. Res. 31: 812816 (2017)
Caucasian. Among these, only ten of them were current
patients of the treatment center (the others were
Data were analyzed using the Statistics Analysis
Software System (SAS Institute Inc., Cary, NC, USA).
The analysis compared the difference between the
active group (BEO) and the control group (distilled
water) in positive and negative affect scores. In addition,
a two-sample t-test was also performed for each
individual item to compare the means for each
treatment group. Statistical assessments were two tailed
and considered significant at p<0.05 and near
significance at 0.05 p<0.1.
No adverse effects were caused by exposure to BEO
aroma as reported by the participants. More
participants participated and completed the trial in the
active group (n= 45) than did those in the control group
(n= 12) (Table 1). There were ten patients in the active
group and none in the control group.
Overall, the active group reported both higher
positive and negative affect scores than did the control
group (Table 2). The mean positive affect score for the
active group was 17% higher than that of the control
group, although the improvement was not considered
statistically significant. The mean negative affect score
for the active group was 15.4% higher than that of the
control group, and the increase was not statistically
significant either. A complete listing of all statistical tests
is contained in Table 2.
No statistically significant difference was observed
for any of the individual items between the active
group and control group (Table 2). However, near-
significant (0.05 <p<0.1) and meaningful differences
(0.4 or above on a scale from 1 to 5) were observed for
several items. Participants in the active group reported
a 48.77% higher score of feeling proudcompared
with the control group. They also reported a 43.36%
higher score of feeling active.However, participants
in the active group also reported a 60% increase of
feeling nervous.
Participants in the waiting room of the mental health
treatment center in the BEO group reported higher
positive affect scores than did the control group.
Participants in the BEO group also showed a smaller
increase in negative affect scores than did the control
group; however, the reasons why are unclear. It could
be due to an effect resulting from the smaller size of
the control group. Interestingly, the control groups
mean negative affect score was already in the very
lower end of the scale. This indicates that there was
probably not much room to improve in negative affect,
partially because the clear majority of participants (47
out of 57) were patientscompanions, who were less
likely to have mental disorders than patients.
Moreover, the improvement in positive affect scores
was greater than the increase in negative affect scores,
although neither of them was statistically significant.
Collectively, this suggests that BEO aromatherapy
Table 2. Summary of PANAS scores in the active group and the control group (N= 57)
group mean
(n= 45)
group SE
(n= 45)
group mean
(n= 12)
group SE
(n= 12)
(active control)
value p-value
1 Interested 2.73 0.18 2.75 0.35 0.02 0.39 55 0.04 0.97
3 Excited 1.69 0.12 1.42 0.24 0.27 0.26 55 1.03 0.31
5 Strong 2.60 0.18 2.33 0.36 0.27 0.31 55 0.67 0.51
9 Enthusiastic 2.22 0.18 1.92 0.35 0.31 0.38 55 0.79 0.44
10 Proud 2.36 0.19 1.58 0.37 0.77 0.41 55 1.87 0.07*
12 Alert 3.13 0.16 2.67 0.30 0.47 0.34 55 1.38 0.17
14 Inspired 2.38 0.18 1.83 0.35 0.54 0.39 55 1.39 0.17
16 Determined 2.93 0.19 2.58 0.37 0.35 0.41 55 0.84 0.40
17 Attentive 2.91 0.15 2.83 0.30 0.08 0.33 55 0.23 0.82
19 Active 1.91 0.14 1.33 0.28 0.58 0.31 55 1.86 0.07*
Total positive 24.87 1.15 21.25 2.22 3.62 2.5 55 1.45 0.15
2 Distressed 1.91 0.17 1.50 0.33 0.41 0.37 55 1.12 0.27
4 Upset 1.53 0.14 1.42 0.28 0.12 0.31 55 0.38 0.71
6 Guilty 1.38 1.14 1.50 0.27 0.12 0.31 55 0.40 0.69
7 Scared 1.60 0.16 1.00 0.31 0.60 0.35 55 1.70 0.10
8 Hostile 1.16 0.08 1.33 0.16 0.18 0.18 55 1 0.32
11 Irritable 1.62 0.15 1.75 0.29 0.13 0.32 55 0.39 0.70
13 Ashamed 1.31 0.15 1.42 0.29 0.11 0.33 55 0.32 0.75
15 Nervous 1.73 0.16 1.08 0.30 0.65 0.34 55 1.92 0.06*
18 Jittery 1.60 1.50 1.33 0.29 0.27 0.33 55 0.82 0.42
20 Afraid 1.57 0.16 1.00 0.30 0.57 0.34 55 1.67 0.10
Total negative 15.38 1.09 13.33 2.12 2.04 2.4 55 0.86 0.40
Note: SE, standard error; PANAS, The Positive and Negative Affect Schedule.
814 X. HAN ET AL.
© 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd. Phytother. Res. 31: 812816 (2017)
might provide beneficial effects on participantsmental
well-being and feelings, as measured by PANAS, in the
waiting room of a mental health treatment center.
A body of clinical research has provided evidence
supporting the therapeutic effects of BEO
aromatherapy on mild mental disorders in a variety
of settings (Navarra et al., 2015). Bergamot essential
oil aromatherapy provided several beneficial effects
to participants including reduced heart rate, blood
pressure, stress responses, depression, and anxiety
(Chang and Shen, 2011; Ni et al., 2013; Navarra
et al., 2015; Watanabe et al., 2015). Although the
BEO mechanism is not fully understood, some studies
suggest that it may trigger the release of discrete
amino acids, which then may act as neurotransmitters
that interact with normal and pathological synaptic
plasticity (Bagetta et al., 2010; Saiyudthong and
Marsden, 2011). The clinical pharmacology of BEO is
out of this studys scope; however, it was recently
reviewed by Mannucci and colleagues (Mannucci
et al., 2017).
Bergamot essential oil aromatherapy was extremely
safe in this study, and no adverse events were reported.
This was largely consistent with existing literature
(Navarra et al., 2015; Mannucci et al., 2017). This might
be partially true because bergamot and other citrus
aromas are common; therefore, people have become
used to these aromas.
To our knowledge, this study provided the first
evidence of the therapeutic efficacy and safety of BEO
aromatherapy in the waiting room of a mental health
treatment center. Although definite conclusions of
BEOs therapeutic properties remain elusive, BEO
aromatherapy may play an important role in a holistic
healthcare approach, especially for those dealing with
issues related to mental health or well-being (Mannucci
et al., 2017).
It is unclear why fewer people were willing to
participate during the control periods than the BEO
periods (ns = 12 vs. 45). This observation appears to
be more apparent for patients of the mental health
treatment center, who had already been diagnosed with
mental health issues: ten patients participated in the
BEO periods, while no patient participated in the
control periods. To the best of our knowledge, this is
unlikely due to any other interventions than the
difference between exposure to BEO aroma and water
vapor. One explanation would be that even very brief
exposure to BEO aroma may somehow make people
(specifically patients with mental issues) become more
willing to participate in clinical trial in the current
setting. If this is true, it can have profound applications
in both clinical trial participation and compliance as well
as many other scenarios.
This study had several limitations. It was designed as a
pilot study to explore the potential benefits of BEO
aromatherapy for mental well-being and feelings. The
study did not have sufficient statistical power to make
definite conclusions mainly due to the small control
group, small overall study size, and study design. The
study design was the best possible option at the time
the trial commenced. We designed it to mimic the real-
life scenarios of aroma inhalation as much as possible.
Furthermore, we intended to minimize the effects that
the treatment center had on the trial and its participants.
Therefore, only current patients of the center and their
companions were invited to participate. Further studies
with designs, such as better controlling participation,
are recommended.
The authors acknowledge the Green House Center (Pleasant Grove,
UT, USA) for allowing us to conduct the study at their facility.
Conflicts of Interest
X.H. and T.P. are employees of dōTERRA (Pleasant
Grove, UT, USA), where the Bergamot essential oil
was manufactured. D.E. is a consulting statistician for
Andrews G, Carter GL. 2001. What people say about their general
practitionerstreatment of anxiety and depression. Med J Aust
175(Suppl): S48S51.
Baba VV, Galperin BL, Lituchy TR. 1999. Occupational mental
health: a study of work-related depression among nurses in
the Caribbean. Int J Nurs Stud 36: 163169.
Bagetta G, Morrone LA, Rombolà L, et al. 2010. Neuropharmacology
of the essential oil of bergamot. Fitoterapia 81: 453461.
Bantz EW, Dolen WK, Chadwick EW, Nelson HS. 1987. Chronic
chlorpheniramine therapy: subsensitivity, drug metabolism,
and compliance. Ann Allergy 59: 341346.
Bruffaerts R, Demyttenaere K, Kessler RC, et al. 2015. The
associations between preexisting mental disorders and
subsequent onset of chronic headaches: a worldwide
epidemiologic perspective. J Pain 16:4252.
Chang K-M, Shen C-W. 2011. Aromatherapy benefits autonomic
nervous system regulation for elementary school faculty in
taiwan. Evid-Based Complement Altern Med 2011: 946537.
Crawford JR, Henry JD. 2004. The positive and negative affect
schedule (PANAS): construct validity, measurement properties
and normative data in a large non-clinical sample. Br J Clin
Psychol 43: 245265.
Etzel JV. 1994. Diphenhydramine-induced acute dystonia.
Pharmacotherapy 14: 492496.
Gerlach J, Larsen EB. 1999. Subjective experience and mental
side-effects of antipsychotic treatment. Acta Psychiatr Scand
Suppl 395:113117.
Hongratanaworakit T. 2011. Aroma-therapeutic effects of
massage blended essential oils on humans. Nat Prod Commun
6: 11991204.
Johnson S, Cooper C, Cartwright S, Donald I, Taylor P, Millet C.
2005. The experience of work-related stress across
occupations. J Manag Psychol 20: 178187.
Jones B, Lal S. 1985. Tardive dyskinesia uncovered after ingestion of
Sominex, an over-the-counter drug. Can J Psychiatry Rev 30:
Kessler RC, Sampson NA, Berglund P, et al. 2015. Anxious and
non-anxious major depressive disorder in the World Health
Organization World Mental Health Surveys. Epidemiol
Psychiatr Sci 24: 210226.
© 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd. Phytother. Res. 31: 812816 (2017)
Lima NGPB, De Sousa DP, Pimenta FCF, et al. 2013. Anxiolytic-like
activity and GC-MS analysis of (R)-(+)-limonene fragrance, a
natural compound found in foods and plants. Pharmacol
Biochem Behav 103:450454.
Linck VM, da Silva AL, Figueiró M, Caramão EB, Moreno PRH,
Elisabetsky E. 2010. Effects of inhaled Linalool in anxiety,
social interaction and aggressive behavior in mice.
Phytomedicine 17: 679683.
Mannucci C, Navarra M, Calapai F, Squeri R, Gangemi S, Calapai G.
2017. Clinical pharmacology of Citrus bergamia: a systematic
review. Phytother Res 31:2739.
McCarthy JM, Trougakos JP, Cheng BH. 2016. Are anxious
workers less productive workers? It depends on the quality
of social exchange. J Appl Psychol 101: 279291.
Mercier A, Kerhuel N, Stalnikiewitz B, et al. 2010. Obstacles to
effective treatment of depression. A general practitioners
postal survey in the north-west region of France. Encéphale
36(Suppl 2): D73D82.
Moss M, Cook J, Wesnes K, Duckett P. 2003. Aromas of rosemary
and lavender essential oils differentially affect cognition and
mood in healthy adults. Int J Neurosci 113 :1538.
Navarra M, Mannucci C, Delbò M, Calapai G. 2015. Citrus
bergamia essential oil: from basic research to clinical
application. Front Pharmacol 6: 36.
Ni C-H, Hou W-H, Kao C-C, et al. 2013. The anxiolytic effect of
aromatherapy on patients awaiting ambulatory surgery: a
randomized controlled trial. Evid-Based Complement Altern
Med 2013: 927419.
Prashar A, Locke IC, Evans CS. 2004. Cytotoxicity of lavender oil and
its major components to human skin cells. Cell Prolif 37:
Rummel-Kluge C, Komossa K, Schwarz S, et al. 2010. Head-to-head
comparisons of metabolic side effects of second generation
antipsychotics in the treatment of schizophrenia: a systematic
review and meta-analysis. Schizophr Res 123: 225233.
Saiyudthong S, Marsden CA. 2011. Acute effects of bergamot oil
on anxiety-related behaviour and corticosterone level in rats.
Phytother Res 25: 858862.
Satou T, Takahashi M, Kasuya H, et al. 2013. Organ accumulation
in mice after inhalation of single or mixed essential oil
compounds. Phytother Res 27: 306311.
Schaefer M, Schmidt F, Folwaczny C, et al. 2003. Adherence and
mental side effects during hepatitis C treatment with
interferon alfa and ribavirin in psychiatric risk groups. Hepatol
Baltim Md 37: 443451.
Seifi Z, Beikmoradi A, Oshvandi K, Poorolajal J, Araghchian M,
Safiaryan R. 2014. The effect of lavender essential oil on
anxiety level in patients undergoing coronary artery bypass
graft surgery: a double-blinded randomized clinical trial. Iran
J Nurs Midwifery Res 19: 574580.
Toda M, Morimoto K. 2008. Effect of lavender aroma on salivary
endocrinological stress markers. Arch Oral Biol 53:
Watanabe E, Kuchta K, Kimura M, Rauwald HW, Kamei T, Imanishi
J. 2015. Effects of bergamot (Citrus bergamia) essential oil
aromatherapy on mood states, parasympathetic nervous
system activity, and salivary cortisol levels in 41 healthy
females. Forsh Komplementmed 22:4349.
Watson D, Clark LA, Tellegen A. 1988. Development and
validation of brief measures of positive and negative affect:
the PANAS scales. J Pers Soc Psychol 54: 10631070.
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© 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd. Phytother. Res. 31: 812816 (2017)

Supplementary resource (1)

... In the study led by Han et al. [69], 57 participants were exposed to bergamot essential oil, which improved the participants' positive feelings by 17% compared with the control group. Another study, led by Matsumoto et al. [70], proved that the Japanese citrus fruit yuzu (Citrus junos Tanaka) EO has an anti-stress effect and eases premenstrual emotional symptoms, namely tension-anxiety, anger-hostility, and fatigue-common. ...
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Citrus production produces about 15 million tons of by-products/waste worldwide every year. Due to their high content of bioactive compounds, several extraction techniques can be applied to obtain extracts rich in valuable compounds and further application into food applications. Distillation and solvent extraction continues to be the most used and applied extraction techniques, followed by newer techniques such as microwave-assisted extraction and pulsed electric field extraction. Although the composition of these extracts and essential oils directly depends on the edaphoclimatic conditions to which the fruit/plant was exposed, the main active compounds are D-limonene, carotenoids, and carbohydrates. Pectin, one of the most abundant carbohydrates present in Citrus peels, can be used as a biodegradable polymer to develop new food packaging, and the extracted bioactive compounds can be easily added directly or indirectly to foods to increase their shelf-life. One of the applications is their incorporation in active food packaging for microbiological and/or oxidation inhibition, prolonging foods' shelf-life and, consequently, contributing to reducing food spoilage. This review highlights some of the most used and effective extraction techniques and the application of the obtained essential oils and extracts directly or indirectly (through active packaging) to foods.
... Lavender inhalation was found to be effective for reducing anxiety [21], autonomic nervous system regulation [22], ensuring good quality of sleep [23], and to be negative for static postural stability [24]. Additionally, citrus inhalation has been reported to help with energy perception, positive feelings, and static postural stability, and has the same anti-anxiety effects as lavender inhalation [24][25][26][27]. ...
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Some athletes utilize olfactory inhalation treatments using ammonia salt and aromatic oils to attain their peak performance or for physical and psychological relaxation. However, there is still a lack of clear evidence on olfactory inhalation treatment and scent types via precise experiments, and there is no research regarding fine motor control performance in activities such as golf putting. Thus, the purpose of this study was to examine the effects of various olfactory inhalations (lavender, citrus, and ammonia) on professional golfers’ 3-meter putting performance (percentage of success), postural stability (CoP area), and heart rate (HR). In order to examine the effects of olfactory treatment on actual automated task performance, ten professional golfers were recruited for the putting task experiment. During the putting task, a biometric shirt was utilized to record the HR changes, and a force plate was used to measure changes in the CoP area. The results were as follows. First, the olfactory inhalation treatment inhibited the putting performance (no inhalation: 68.75%; lavender: 51.25%; citrus: 40.00%; ammonia: 52.50%); however, no statistically significant difference was found (p = 0.115). Second, the olfactory inhalation treatment inhibited postural stability while putting; it had a partially statistically significant lower value (address: p = 0.000; downswing: p = 0.035; total putting section: p = 0.047). Third, the olfactory inhalation treatment decreased the HR during putting; however, there was no statistically significant difference between groups (address: p = 0.838; putting: p = 0.878; total: p = 0.666). This study implies that olfactory inhalation affects putting performance, postural stability, and HR. The effect size results for the olfactory treatment in the CoP area during the putting task (address: η2 = 0.524; downswing: η2 = 0.349; total putting section: η2 = 0.298) suggest that arousal regulation through olfactory inhalation may have negative effects on dynamic postural stability in static tasks such as golf putting, showing the direction of its useful application for athletes in sports.
... As a complementary approach, inhalation aromatherapy is used widely for treating depression (Koo, 2017;Liang et al., 2021). Numerous studies have indicated that some of the critical constituents of essential oils may reduce depressive symptoms markedly via nasal-brain pathways, including those in patients with severe depressive disorder, postpartum women, postmenopausal women, and cancer patients (Chan et al., 2015;Han et al., 2017). In addition, the researchers discovered that citrus scents containing 95% citral were often more appealing and pleasant to people who felt sad (Pause et al., 2001). ...
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Mood disorders, also often referred to as affective disorders, are a group of psychiatric illnesses that severely impact mood and its related functions. The high medical expenditures have placed a significant financial burden on patients and their families. Aromatherapy is an alternative and complementary treatment that utilizes essential oils (EOs) or volatile oils (VOs) to achieve major therapeutic goals. In general, EOs are volatile chemicals that enter the body primarily through skin absorption and/or nasal inhalation. In addition, they can work through oral administration. Inhalation aromatherapy has shown unique advantages for treating mood disorders, especially depression, anxiety and mental disorders such as sleep disorder, which have been validated over the last decade through clinical and animal studies. Accumulating evidence has shown that EOs or VOs can bypass the blood-brain barrier to target brain tissue through the nasal-brain pathway. Subsequently, they act on the cerebral cortex, thalamus, and limbic system in the brain to improve symptoms of anxiety, depression and improve sleep quality. Here, we review the natural aromatic plants’ volatiles or essential oils used commonly as adjuncts to manage mood disorders and illustrate the mechanisms of inhalation aromatherapy, and mainly summarized the application of transnasal inhalation aromatherapy in depression, anxiety, and sleep disorders. We conclude that aromatherapy does not cause side-effects, which is vastly different from commonly used psychotropic drugs. Inhalation aromatherapy via brain-targeted nasal delivery offers potentially efficacious treatment for mental disorders and merits further study.
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Rhodiola crenulata (RC) and Rhodiola fastigiata (RF) are representative species of Rhodiola with well-accepted health benefits; the roots are the medicinal part. However, prior to this study, the differences in phytochemicals between these two species and different parts of the same species remained unclear. Using LC-ESI-MS/MS, HS-SPME-GC-MS, chemical and sensory analyses, volatile compounds and non-volatile compounds, and antioxidant activities of the roots of Rhodiola crenulata and Rhodiola fastigiata and four parts (roots, leaves, flowers, and above-ground stems) of RC were investigated. The volatile compounds and non-volatile compounds of RC roots exhibited upregulation overall compared to those of RF roots, and the odorousness, phenolic content, and antioxidant activity were more pronounced in the RC roots. The phenolic content and antioxidant activity of roots and leaves, alongside the odorousness of roots and flowers, were more significant among the four parts of RC, and the RC roots and RC flowers exhibited similar odorousness. Comparison of non-volatile differential metabolites between RC roots and RC leaves showed upregulations of saccharides and phospholipids, and minor upregulations of flavonoids and phenylpropanoids in the roots; in addition, amino acids, organic acids, and vitamins were upregulated in the leaves. These results revealed the following: 1) RC roots are superior to RF roots regarding volatile compounds and non-volatile compounds, and antioxidant activity; 2) it is more favorable to select RC roots for exploiting volatile compounds compared with RC flowers in consideration of the biomass available; 3) in terms of non-volatile compounds, and antioxidant ability, RC leaves are also of great value in addition to RC roots, though these two parts show distinct characteristics.
Objective: To compare the effectiveness of aromatherapy with lavender essential oil (EO) versus an EO synergy on psycho-emotional symptoms and fatigue of nursing professionals in the COVID-19 setting. Materials and Methods: This is a quasi-experimental pilot study conducted in 2020. The professionals were randomized in Group 1 — lavender, and in Group 2 — lavender and other EOs synergy. The instruments were validated in Brazil, namely the Self-Reporting Questionnaire (SRQ-20) and the Fatigue Pictogram, which were applied at three moments: before the intervention, after 21 days of intervention, and three weeks after the end of the intervention follow-up. The data were evaluated using Pearson’s x2 test or Fisher’s exact test (dichotomous variables) and Student’s t-test or Mann-Whitney test (continuous variables). Results: A total of 18 professionals participated, and both groups presented improved SRQ-20 scores (p < 0.010), which was maintained in the follow-up for Group 1 compared to the pre-intervention moment (p = 0.033). There was a significant decrease in fatigue in professionals in both groups (p = 0.010), but no difference was observed in the improvement of the impact of fatigue on daily life. Conclusions: There was a reduction in psycho-emotional symptoms and fatigue in nursing professionals who used aromatherapy during the COVID-19 pandemic in both groups.
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Bu araştırmada, Türkiye’de Cumhuriyet sonrası kırsal alanlarda yapılan çalışmalar incelenmiş; tezler, makaleler, bildiriler gibi çalışmalardan yararlanılmış; Avrupa Birliği’nin Türkiye’de kırsal alanlar konusundaki ilerleme raporlarından; Türkiye hükümetlerinin kırsal kalkınma strateji, plan ve programlarından faydalanılmıştır. Çalışma ile, geçmiş dönem kırsal politikalarının ayrıntılı incelenip öneriler ortaya konulması, gelecekte Türkiye’nin kırsal kalkınma konusundaki politikalarının oluşturulmasında karar vericilere hedefler, öncelikler ve faaliyetler konularında katkıda bulunulması amaçlanmıştır.
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The COVID-19 pandemic has emphasized the significance of utilizing essential oils (EO) as one of the holistic ways of supporting and enhancing health. As a consequence of growing knowledge of connected health concerns, people all over the world are looking for natural ways to avoid different ailments. It has been proven that excellent health and psychological awareness increase the human body's immune response, therefore boosting disease resistance. Essential oils are derived in a number 76 of ways from valued plants containing active chemicals with medicinal qualities. In Malaysia, many have used EO in their daily lives. This paper identifies the hierarchy of importance among factors which contribute towards the usage frequency of essential oils in Malaysia using an artificial neural network. Two-layer neural network (NN) models have been applied, which are multilayer perceptron (MLP) and radial basis function (RBF). Based on the analysis done, RBF-NN performed the best with SSE=4.436 and RE=0.548. It can be concluded that, based on sensitivity analysis, the top five factors toward usage frequency are consumption, age, external use, clinic visit, and occasion, with normalized importance of 100%, 90.8%, 89.3%, 68.2%, and 42.2% respectively.
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In this article, we draw from Conservation of Resources Theory to advance and test a framework which predicts that emotional exhaustion plays an explanatory role underlying the relation between workplace anxiety and job performance. Further, we draw from social exchange theories to predict that leader-member exchange and coworker exchange will mitigate the harmful effects of anxiety on job performance. Findings across a 3-wave study of police officers supported our model. Emotional exhaustion mediated the link between workplace anxiety and job performance, over and above the effect of cognitive interference. Further, coworker exchange mitigated the positive relation between anxiety and emotional exhaustion, while leader-member exchange mitigated the negative relation between emotional exhaustion and job performance. This study elucidates the effects of workplace anxiety on resource depletion via emotional exhaustion and highlights the value of drawing on social resources to offset the potentially harmful effects of workplace anxiety on job performance. (PsycINFO Database Record
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Citrus bergamia Risso et Poiteau, also known as "Bergamot," is a plant belonging to the Rutaceae family, defined as a hybrid of bitter orange and lemon. It is an endemic plant of the Calabria region (Italy). Bergamot fruit is primarily used for the extraction of its essential oil (bergamot essential oil: BEO), employed in perfume, cosmetics, food, and confections. The aim of this review was to collect recent data from the literature on C. bergamia essential oil and, through a critical analysis, focus on safety and the beneficial effects on human health. Clinical studies on the therapeutic applications of BEO exclusively focus on the field of aromatherapy, suggesting that its use can be useful for reducing anxiety and stress.
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Background: To examine cross-national patterns and correlates of lifetime and 12-month comorbid DSM-IV anxiety disorders among people with lifetime and 12-month DSM-IV major depressive disorder (MDD). Method: Nationally or regionally representative epidemiological interviews were administered to 74 045 adults in 27 surveys across 24 countries in the WHO World Mental Health (WMH) Surveys. DSM-IV MDD, a wide range of comorbid DSM-IV anxiety disorders, and a number of correlates were assessed with the WHO Composite International Diagnostic Interview (CIDI). Results: 45.7% of respondents with lifetime MDD (32.0-46.5% inter-quartile range (IQR) across surveys) had one of more lifetime anxiety disorders. A slightly higher proportion of respondents with 12-month MDD had lifetime anxiety disorders (51.7%, 37.8-54.0% IQR) and only slightly lower proportions of respondents with 12-month MDD had 12-month anxiety disorders (41.6%, 29.9-47.2% IQR). Two-thirds (68%) of respondents with lifetime comorbid anxiety disorders and MDD reported an earlier age-of-onset (AOO) of their first anxiety disorder than their MDD, while 13.5% reported an earlier AOO of MDD and the remaining 18.5% reported the same AOO of both disorders. Women and previously married people had consistently elevated rates of lifetime and 12-month MDD as well as comorbid anxiety disorders. Consistently higher proportions of respondents with 12-month anxious than non-anxious MDD reported severe role impairment (64.4 v. 46.0%; χ 2 1 = 187.0, p < 0.001) and suicide ideation (19.5 v. 8.9%; χ 2 1 = 71.6, p < 0.001). Significantly more respondents with 12-month anxious than non-anxious MDD received treatment for their depression in the 12 months before interview, but this difference was more pronounced in high-income countries (68.8 v. 45.4%; χ 2 1 = 108.8, p < 0.001) than low/middle-income countries (30.3 v. 20.6%; χ 2 1 = 11.7, p < 0.001). Conclusions: Patterns and correlates of comorbid DSM-IV anxiety disorders among people with DSM-IV MDD are similar across WMH countries. The narrow IQR of the proportion of respondents with temporally prior AOO of anxiety disorders than comorbid MDD (69.6-74.7%) is especially noteworthy. However, the fact that these proportions are not higher among respondents with 12-month than lifetime comorbidity means that temporal priority between lifetime anxiety disorders and MDD is not related to MDD persistence among people with anxious MDD. This, in turn, raises complex questions about the relative importance of temporally primary anxiety disorders as risk markers v. causal risk factors for subsequent MDD onset and persistence, including the possibility that anxiety disorders might primarily be risk markers for MDD onset and causal risk factors for MDD persistence.
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Open heart surgery can cause high levels of anxiety in patients. Nowadays, lavender essential oil is widely used in medical research. This study was conducted with an aim to investigate the effects of lavender essential oil to reduce the anxiety of patients after coronary artery bypass surgery. This research is double-blinded randomized controlled trial on 60 patients who had undergone coronary artery bypass surgery in a 2-day intervention targeting reduction of anxiety. This study was conducted in Ekbatan Therapeutic and Educational Center, Hamadan city, Iran, in 2013. The patients in the inhalation aromatherapy group inhaled two drops of 2% lavender essential oil and those in the control group inhaled two drops of distilled water as placebo for 20 min on the 2(nd) and 3(rd) days after surgery. The level of anxiety was evaluated by Spielberger's State Anxiety questionnaire before and after intervention and the vital signs were documented as well. Data were analyzed using Stata 11 (Stata Corp., College Station, TX, USA) by independent t-test for continuous variables and Chi-square test for categorical variables. The mean score of anxiety in the aromatherapy group was 48.73 ± 5.08 and in the control group was 48 ± 6.98 before the intervention (P = 0.64), which reduced after the intervention to 42.6 ± 5.44 and 42.73 ± 7.30, respectively. On the 3(rd) day after surgery, the mean score of anxiety in the aromatherapy group was 46.76 ± 4.07 and in the control group was 46.53 ± 7.05 before the intervention, which reduced to 41.33 ± 3.65 and 41.56 ± 6.18, respectively, after the intervention. However, there was no statistically significant difference in the mean scores of anxiety between the aromatherapy and control groups. Lavender essential oil has no significant effect on anxiety in patients after coronary artery bypass surgery, although it decreased the level of anxiety in the patients.
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The aim of this study was to determine if aromatherapy could reduce preoperative anxiety in ambulatory surgery patients. A total of 109 preoperative patients were randomly assigned to experimental (bergamot essential oil) and control (water vapor) conditions and their responses to the State Trait Anxiety Inventory and vital signs were monitored. Patients were stratified by previous surgical experience, but that did not influence the results. All those exposed to bergamot essential oil aromatherapy showed a greater reduction in preoperative anxiety than those in the control groups. Aromatherapy may be a useful part of a holistic approach to reducing preoperative anxiety before ambulatory surgery.
Citrus bergamia Risso et Poiteau (“Bergamot”) originated from the Mediterranean ecoregion (southern Italy, Calabria). Bergamot essential oil (BEO) is used in perfumes, cosmetics, and for stress reduction. Juice from C. bergamia has been used for hyperlipidemia. We evaluated literature published on C. bergamia clinical applications. Clinical trials on C. bergamia not combined with other substances, published in English, were searched. We selected ten articles, six describing BEO effects on stress, three reporting effects of polyphenolic fraction of C. bergamia juice in hyperlipidemia and the last describing BEO effects in chronic psoriasis. Clinical studies were analyzed following Consolidated Standards of Reporting Trials for herbal therapy. Studies were conducted on small sample sizes and not have high quality level. Analysis indicates that BEO aromatherapy could be safe and useful to reduce stress symptoms. One study suggests its potential supportive role in ultraviolet B therapy against psoriasis. Supplementation with polyphenols from bergamot juice reduces plasma lipids and improves lipoprotein profile in moderate hyperlipidemia. Effectiveness and safety of C. bergamia cannot be definitively drawn because of publication bias and low quality level of the majority of studies. Further large-scale trials with rigorous design are required to define the role of C. bergamia in clinical practice. Copyright
Bergamot essential oil (BEO) is commonly used against psychological stress and anxiety in aromatherapy. The primary aim of the present study was to obtain first clinical evidence for these psychological and physiological effects. A secondary aim was to achieve some fundamental understanding of the relevant pharmacological processes. Endocrinological, physiological, and psychological effects of BEO vapor inhalation on 41 healthy females were tested using a random crossover study design. Volunteers were exposed to 3 experimental setups (rest (R), rest + water vapor (RW), rest + water vapor + bergamot essential oil (RWB)) for 15 min each. Immediately after each setup, saliva samples were collected and the volunteers rested for 10 min. Subsequently, they completed the Profile of Mood States, State-Trait Anxiety Inventory, and Fatigue Self-Check List. High-frequency (HF) heart rate values, an indicator for parasympathetic nervous system activity, were calculated from heart rate variability values measured both during the 15 min of the experiment and during the subsequent 10 min of rest. Salivary cortisol (CS) levels in the saliva samples were analyzed using ELISA. CS of all 3 conditions R, RW, and RWB were found to be significantly distinct (p = 0.003). In the subsequent multiple comparison test, the CS value of RWB was significantly lower when compared to the R setup. When comparing the HF values of the RWB setup during the 10 min of rest after the experiment to those of RW, this parameter was significantly increased (p = 0.026) in the RWB setup for which scores for negative emotions and fatigue were also improved. These results demonstrate that BEO inhaled together with water vapor exerts psychological and physiological effects in a relatively short time. © 2015 S. Karger GmbH, Freiburg.
Although there is a significant association between pre-existing depression and later onset of chronic headache, the extent to which other pre-existing mental disorders are associated with subsequent onset of headache in the general population is not known. Also unknown is the extent to which these associations vary by gender or by life course. We report global data from the WHO’s World Mental Health surveys (N=52,095), in which, by means of the Composite International Diagnostic Interview-3.0 (CIDI-3.0), 16 DSM-IV mental disorders were retrospectively assessed in terms of lifetime prevalence and age-of-onset. Frequent or severe headaches were assessed using self-reports. After adjustment for covariates, survival models showed a moderate but consistent association between pre-existing mood (ORs 1.3-1.4), anxiety (ORs 1.2-1.7), and impulse-control disorders (ORs 1.7-1.9) and the subsequent onset of headache. We also found a dose-response relationship between the number of pre-existing mental disorders and subsequent headache onset (OR ranging between 1.9 for 1 up to 3.4 for 5+ pre-existing mental disorders). Our findings suggest a consistent and pervasive relationship between a wide range of pre-existing mental disorders and the subsequent onset of headaches. This highlights the importance of assessing a broad range of mental disorders, not just depression, as specific risk factors for the subsequent onset of frequent or severe headaches. Perspective This study shows that there is a temporal association between a broad range of pre-existing mental disorders and the subsequent onset of severe or frequent headaches in general population sample across the world.
Context and aim Depression is a quite common condition, and its treatment is mainly provided by General Practitioner (GP). It is already known that detection and treatment requires significant improvement. The well known and high consumption of antidepressant drugs in France, the highest of all other European countries, requires specific studies. The causes of this situation are not clear and seem to be numerous: Patient's demands, social claims; lack of initial and continuous medical education, bad GP demographic trends, and lack of them in rural areas; pharmaceutical company pressure; and organisation of the health care system. GP are the main medical actors of the primary care system in France. The aim of this study was to survey GP perceptions on secondary care services, seek the views and barriers to the provision of good services, and ask them about perceptions and solutions they could suggest. Methods A structured postal questionnaire was sent to all GP of the north-west region of France, asking physicians about obstacles perceived when taking care of depressive patients; factors influencing the use of services, specialised advice, treatments, access to psychiatrists and psychological care. Their psychiatric knowledge and demographic data were also assessed. Quantitative data were analysed using Epi-Info software, and qualitative data were transcribed and coded manually. Results A total of 25% of the GP returned the questionnaire (n = 2097 in 8709). The sample profile was the same as the studied population. Less than a third of the GP (28%) were aware of the clinical guidelines on depression, and less than a fifth (18%) had clinical experience of psychiatry during their studies. Lack of time was not the main obstacle assessed by the GP. Their complaints were about lack of mental health services, difficulty in accessing services, and about general liaison between primary and secondary health care services: they reported difficulties obtaining quick and good response from the specialist either for emergency or non emergency cases. Regarding secondary care, they mainly referred to the psychiatrist, rather than to the psychologist, probably because this second option is not reimbursed by the social security system. Not surprisingly, medication was cited as the most frequently used treatment, followed by psychotherapy and cognitive behavioral therapy (CBT), and almost never self help literature and self help groups. Trained GP considered they were much more comfortable coping with depressed patients, less frequently using secondary care providers, and easily alternative solutions rather than antidepressant drugs. This situation suggests the usefulness of medical education, and is attested by many qualitative answers. Discussion It is not sure that the low rate of knowledge of the guidelines should be judged only as a lack of professionalism. According to the “French Society of Primary Care”, clinical guidelines need updating, and it is known that those available could be useful only for half of the situations encountered in primary care. Operational propositions urgently need to be proposed. Recent questioning of the real interest of pharmaceutical options in the treatment of depression is another argument. Nor can we wait for a hypothetic rise in the demographic situation. The GP have several propositions to improve these problems, e.g. continuous medical education (CME) focusing on “patient centred therapy”, dedicated hotline or circuit for depressed people, and an adapted sociomedical directory. They also feel that political awareness about lack of physicians is required, but say that improving quality of care does not rely only on improving demographics. They ask for funds for psychological care. When thinking about the circuit of care, the role of all care providers, and their communication, a global vision appears unavoidable, which would get rid of the divisions between out-patients and the hospital. Conclusion Despite an unavoidable questioning on the dysfunctions of the health care system, quality of care and probably pharmaceutical consumption for the depressed patient might be improved by simple tools, such as adapted CME for primary care physicians, and communication improvement between secondary and primary care systems.