Is bergamot oil beneficial for relaxation?

There is limited human evidence that bergamot essential oil (BEO) aromatherapy may reduce physiological indicators of stress in already-calm situations, which is consistent with a relaxation-promoting effect, although the evidence for any given indicator is mixed. A 2009 RCT of BEO aromatherapy alone or in combination with soft music, in young adults without any known health conditions, found that soft music, BEO aromatherapy, and the combination of both had positive effects on measures of heart rate variability (HRV).^[1] BEO aromatherapy significantly decreased the ratio of low-frequency variability (LF) to high-frequency variability (HF), indicating increased parasympathetic (“rest and digest”) and decreased sympathetic (“fight or flight”) activity; other studies have observed that this LF:HF ratio increases in stressful situations,^[2] so its reduction is consistent with relaxation. Similarly, although a 2015 study of BEO aromatherapy in women with no known health issues didn’t find a significant effect on HF, it did find a significant reduction in levels of salivary cortisol, which has been linked to stress.^[3]