Aromatherapy & Insomnia: The Good, the Bad and the Smelly

Yesterday the Sleep Education Blog reported that smells can affect the emotional content of dreams. What about insomnia – can smells improve the quality of your sleep?

Aromatherapy is one form of complimentary and alternative medicine - or CAM. It involves the use of fragrant, essential oils from plants. Most often the essential oils are inhaled or applied to the skin; they may be added to bathwater or to a lotion.

How does aromatherapy work? The National Cancer Institute reports that there are different theories. One theory involves smell receptors in the nose; these receptors may respond to the scent by sending chemical messages to the brain.

A 2006 review reported that essential oils may enter the bloodstream; it suggested that aromatherapy may act like a drug.

Is sleep-related aromatherapy effective? Conclusive scientific evidence is lacking. But in recent years more studies have been conducted as interest in CAM has grown. Most of these studies have focused on the herb lavender.

A 2008 study suggested that the aroma of lavender may promote sleep in very young infants. In Korea a 2006 study involved female college students; it found that lavender had a positive effect on insomnia and depression.

A 2005 study reported that lavender may be a “mild sedative;” it may promote deep sleep in young men and women. Another study in 2005 found that lavender improved sleep quality in people with insomnia; women and younger volunteers showed the most improvement.

But a 2006 study found no sleep benefits when children with autism were given a massage with lavender oil.

Are there any side effects or risks? The National Cancer Institute warns that lavender may have some “hormone-like effects;” as a result it is unclear if lavender is safe for women with a high risk for breast cancer.

The NCCAM reports that lavender can cause skin irritation; it also may be poisonous if taken by mouth.

Other proven treatments for insomnia are available. Both cognitive behavioral therapy and medications are effective. A board-certified sleep specialist can determine which treatment is best for you. Contact an AASM-accredited sleep disorders center if you have an ongoing problem with insomnia.

Image by David Turner

The Smell of Sleep & Dreams

A new study examined how your sense of smell may affect your dreams.

The small study from Germany involved 15 volunteers. They were studied using sensory stimulation during the sleep stage of rapid eye movement sleep – or REM sleep.

The study compared two smells with a control condition. One smell involved hydrogen sulphide – the smell of rotten eggs. The other smell involved phenyl ethyl alcohol – the smell of roses.

Results show that the “olfactory stimuli” significantly affected the emotional content of dreams. The smell of roses yielded dreams with a more positive tone; the smell of rotten eggs was followed by dreams that had a more negative tone.

But the smells were not directly included in the dream content; volunteers did not dream about smelling a rose or rotten eggs.

The authors report that smells are unlikely to wake you from sleep; so olfactory stimulation is likely to be included in dreams as the sleeping brain processes sensory information.

The authors conclude that it would be interesting to study the effect of pleasant smells on nightmares.

Image by Joe Penniston