New findings from a small study suggest that the scent of essential oil distilled from Hinoki tree roots may support more restful sleep. People who slept near the scent experienced fewer nighttime awakenings and reported feeling more alert in the morning, compared with conditions without the scent. The study also recorded brain-wave changes associated with a smoother transition into sleep.
While the results are promising, the study was small, and the findings are associations rather than proof of cause and effect. The oil comes from a part of the tree that is often discarded in forestry, so the researchers frame it as a potentially overlooked byproduct. More research would be needed before recommending it as a sleep aid.