In 12 women ages 35 to 60, two weeks of hinoki-root scent at home lined up with fewer night awakenings

What the research found

Study (small home crossover; 12 Japanese women ages 35 to 60). ScienceDaily carried the Kyushu University account on 6 October 2026. Fadilla Zennifa, Kuniyoshi Shimizu, and colleagues report in the Journal of Wood Science (2026; doi 10.1186/s10086-026-02296-3). The oil came from roots of hinoki, Chamaecyparis obtusa, a timber tree whose roots are often discarded. Each woman used the oil for two weeks and an unscented control for two weeks, in random order, single-blind. Three drops went into a paper cup; she inhaled for 10 seconds, then left the cup about 30 centimeters from her nose overnight. A headband recorded brain waves and a watch tracked sleep. By day 13, the oil period was linked with feeling less sleepy and more recovered on waking, and the watches showed fewer awakenings. After seven days, delta-wave activity rose around sleep onset. The scent was rated more relaxing than the control. The sample is 12 people. This is not a sleep medicine, and the release does not compare it with treatment for a sleep disorder. Educational notes. This is not medical advice.

Evidence level: Human study. A study in people, but an association isn't proof of cause.

Read the original at Kyushu University / Journal of Wood Science