How essential are essential oils? Arometherapy fans claim fragrances can eliminate toxins and reduce stress, but the science behind it remains less conclusive.

What The Nose Knows Best—Why It Matters

Concentrated plant extracts have been used medicinally for over , promising relief from anxiety, stress, depression, and a whole slew of other mental and physical ailments . Setzer, WN. Department of Chemistry, University of Alabama in Huntsville, Huntsville, Alabama. National Product Communications 2009 September; 4(9): 1305-16.. But apart from ancient tradition, there might in fact be some science behind these scents. Aromatherapy is believed to stimulate smell receptors in the nose, which then send messages through the and to the part of the brain the brain that controls emotions . Herz, RS. Department of Psychiatry and Human Behavior, Warren Alpert Medical School, Brown University, Providence, Rhode Island. The International Journal of Neuroscience 2009; 119(2): 263-90.. From hospitals to health spas, essential oils are administered through inhalants, diffusers, and massage (definitely not the worst way to take the pain away!) to trigger positive emotions and calm the bad. Deciphering which whiffs are worthwhile, though, can get a little iffy.

Making Sense of Scents—The Answer/Debate

While it may not be surprising that a pleasant scent can improve one’s mood and freshen up a foul-smelling room, researchers have yet to reach a consensus on the benefits of hitting the Whole Foods’ homeopathy aisle. Consider , most popular for its purported “tension taming” effects. Recent research showed sniffing these aromatic florals along with rosemary reduced stress in graduate nursing students during exams McCaffrey, R., Thomas, DJ., Kinzelman, AO. Christine E. Lynn College of Nursing, Florida Atlantic University, Boca Raton, Florida. Holistic Nursing Practice 2009 March-April; 23(2): 88-93.. Another study, however, found the sweet-smelling scent showed few signs of reducing anxiety in dental patients dreading upcoming procedures, though it did seem to lower anxiety in those experiencing more immediate stress . Kritsidima, M., Newton, T., Asimakopoulou, K. King's College London, Dental Institute, Denmark Hill, London, United Kingdom. Community Dentistry and Oral Epidemiology 2010 February; 38(1): 83-7.. To confuse matters more, one of the largest studies on aromatherapy to date found no evidence of lavender's stress-reducing properties when measuring heart rate, blood pressure, stress hormones, and immune function . Kiecolt-Glaser, JK., Graham, JE., Malarkey, WB., et al. Department of Psychiatry, Ohio State University, Columbus, Ohio. Psychoneuroendocrinology 2008 April; 33(3): 328-39.. In the same study, it was lemon oil, a suspected stimulant, that showed the most promise to boost subjects’ mood, though without any measurable physiological effects . Kiecolt-Glaser, JK., Graham, JE., Malarkey, WB., et al. Department of Psychiatry, Ohio State University, Columbus, Ohio. Psychoneuroendocrinology 2008 April; 33(3): 328-39.. Still, despite consistency in the findings, researchers aren’t ready to write off aromatherapy just yet. With more data and greater insight into the mind's physiology, there may yet be a way to make sense of these sneaky scents. DISCLAIMER: Unless authorized by a doctor or trained professional, essential oils should never be taken by mouth, as oils are quite toxic. (And for the rest of them, just think: It takes about to make one pound of plant extract. Probably not the tastiest going down!)

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