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 aromatherapycan be an effective adjunct treatment to improve individuals' mental health and well-being. © 2017 The Authors. Phytotherapy Research published by John Wiley&Sons Ltd.

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 havehigh 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 clinicalpractice. Copyright © 2016 John Wiley&Sons, Ltd.