Aromatherapy in practice; effects of an eightweek intervention on self-reported stress and hair cortisol levels

Stress and its consequences for health and wellbeing is an ongoing problem in the modern era. The potential for aromatherapy to offer a safe, effective and widely available treatment has been considered but the scientific evaluation has often fallen short. In this study we investigated the potential for the aroma of a blend of essential oils to impact on self-reported stress and cortisol levels as a biomarker of chronic stress. Sixty-six clients of clinical aromatherapists were recruited along with a control group of 33 healthy but stressed individuals. Aromatherapy clients followed an eight-week intervention programme that employed either a traditionally extracted or carbon dioxide extracted blend of essential oils. Control participants received no intervention. All participants completed self-report questionnaires at the start and end of the intervention period and provided two hair samples for the evaluation of cortisol levels in the preceding month. Data analysis revealed that the aromatherapy interventions produced significant reductions in self-reported stress, anxiety and mood disturbance with medium sized effects. Hair cortisol levels also significantly declined from pre- to post- treatment with a medium sized effect for both aromatherapy groups. No changes were seen in the control group for any variables. These findings clearly support the effectiveness of clinical aromatherapy practice for the treatment of chronic stress and suggests that method of extraction of the essential oils is not a critical factor. The potential for aromatherapy to contribute more widely to the democratisation of health care as self-care warrants further investigation.