Lavender is the most studied sleep-promoting scent, but it’s far from the only option. Cedarwood, bergamot, sandalwood, valerian, and jasmine all show measurable effects on sleep quality in research settings. A recent meta-analysis found that inhaling these kinds of aromatic oils can shorten the time it takes to fall asleep, lengthen total sleep duration, and improve how rested people feel the next day. The effects are modest but consistent, and the safety profile is strong for most adults.
Lavender: The Most Researched Option
Lavender contains five key compounds that promote sleep: linalool, d-limonene, 1,8-cineole, linalyl acetate, and terpinene-4-ol. These compounds work through your nose, not just as a pleasant background smell. Research published in the Journal of Ethnopharmacology traced the exact pathway: scent molecules travel through the olfactory system and activate calming neurons in a part of the brain called the central amygdala. When researchers blocked the olfactory pathway in animal studies, lavender’s sleep-promoting effects disappeared entirely. The same happened when they silenced those specific calming neurons. In other words, lavender doesn’t just relax you psychologically. It triggers a measurable neurological response that dials down arousal.
This mechanism helps explain why lavender consistently outperforms other scents in sleep studies. It shortens the time to fall asleep, reduces nighttime waking, and improves self-reported sleep quality. If you’re only going to try one scent, lavender has the deepest evidence behind it.
Bergamot: Lowers Stress Hormones Before Bed
Bergamot, the citrus oil that gives Earl Grey tea its distinctive flavor, works on sleep through a different angle. Rather than directly sedating you, it reduces the physiological markers of stress that keep you awake. In a study of 41 healthy women, inhaling bergamot oil dissolved in water vapor significantly lowered salivary cortisol, your body’s primary stress hormone. The effect was stronger than rest alone or rest with plain water vapor.
Bergamot also increased parasympathetic nervous system activity, the “rest and digest” branch that slows your heart rate and relaxes your muscles. This shift didn’t happen during the 15 minutes of exposure itself but showed up in the 10 minutes of rest afterward, suggesting bergamot primes your body for relaxation rather than knocking you out instantly. If your sleep trouble is tied to an anxious, racing mind at bedtime, bergamot targets that problem specifically.
Cedarwood and Sandalwood: Sedation Through Different Pathways
Cedarwood oil contains a compound called cedrol that acts as a sedative. In animal studies, inhaling cedrol significantly reduced spontaneous movement and extended sleep duration. What makes cedarwood interesting is that it appears to work through a pathway other than the olfactory system. Researchers found that its sedative effects persisted regardless of whether the olfactory nerves were functioning normally, suggesting the compounds may enter the bloodstream through the lungs and act on the brain directly.
Sandalwood operates similarly. Its active compound, santalol, has documented central nervous system depressant effects. When inhaled at very low concentrations, santalol decreased total waking time and increased non-REM sleep, the deep, restorative stage your body needs most. Like cedarwood, sandalwood likely acts through the circulatory system rather than purely through smell. Both oils have a warm, woody quality that many people find grounding, which may add a psychological comfort layer on top of the pharmacological effects.
Valerian: Targets Serotonin and Anxiety
Valerian root is well known as a sleep supplement in capsule form, but its essential oil also shows promise when inhaled. The key active compound, caryophyllene, works on a completely different neurotransmitter system than lavender. While lavender activates calming GABA neurons, valerian oil appears to boost serotonin activity and then increase both serotonin and GABA levels downstream. In studies on rats with insomnia, valerian essential oil significantly prolonged sleep duration and reduced tension and anxiety behaviors.
This dual action on both serotonin and GABA makes valerian oil potentially useful for people whose sleep problems are tangled up with anxiety. The smell is earthier and more pungent than lavender or bergamot, so it’s not for everyone. Blending it with a more pleasant scent can help.
Jasmine: A Less Studied Alternative
Jasmine has a reputation as a sleep aid, though the research is thinner than for lavender or bergamot. In one randomized crossover trial, researchers tested a synthetic jasmine scent combined with lavender oil and passionflower herb on 30 people who had trouble falling asleep and experienced frequent nighttime awakenings. Because jasmine was tested alongside other ingredients rather than alone, it’s harder to isolate its individual contribution. The sweet, floral scent is pleasant to most people, and there’s no evidence it disrupts sleep, but the case for jasmine as a standalone sleep scent isn’t as strong as the options above.
How Well Does Aromatherapy Actually Work?
A 2025 systematic review and meta-analysis pooled results across multiple trials and found that inhalation aromatherapy improved every dimension of sleep quality measured: overall quality, time to fall asleep, sleep efficiency, sleep disturbances, daytime function, and total sleep duration. The improvements were statistically significant across the board, with the strongest effects on sleep quality and time to fall asleep.
That said, it’s worth being realistic about the size of these effects. Aromatherapy is not a replacement for addressing the root causes of serious insomnia. The British Psychological Society flagged that the overall evidence for any single scent is still limited, and delivery method seems to matter. Most positive studies used diffusers or direct inhalation rather than pillow sprays, though head-to-head comparisons of delivery methods are scarce. Aromatherapy works best as one piece of a sleep routine, alongside consistent bedtimes, a dark room, and managing stress.
How to Use Sleep Scents Safely
An ultrasonic diffuser is the most common way to scent a bedroom. Running it for 15 to 30 minutes before you get into bed, rather than all night, gives you enough exposure to trigger the physiological effects without overwhelming your senses or drying out your airways. You can also place a few drops of oil on a cotton ball near your pillow or use a linen spray formulated with essential oils.
Topical application, like rubbing diluted oil on your wrists or temples, delivers the scent close to your nose while also allowing some absorption through the skin. If you go this route, always dilute essential oils in a carrier oil like jojoba or coconut oil first. Undiluted essential oils can irritate or burn the skin.
A Warning for Pet Owners
Many of the most popular sleep-promoting oils are toxic to cats and potentially harmful to dogs. According to the Texas A&M College of Veterinary Medicine, diffused oils are especially dangerous for cats because inhaled oil droplets can cause a type of pneumonia. Their list of toxic oils includes lavender, bergamot, sandalwood, eucalyptus, and many others. If you share a bedroom with a cat, avoid diffusing essential oils in that space entirely. Dog owners should also check with a veterinarian before introducing any new oil into shared living areas.