Comprehensive article from Dr Mercola

Scents Can Alter Your Nervous System

When you inhale the fragrance of an essential oil, the aroma penetrates your bloodstream via your lungs,3 and this is thought to be one of the mechanisms by which aromatherapy exerts its physiological effects. Essential oils are also easily absorbed through your skin when applied topically.

The fragrance also affects the limbic system in your brain, which controls both memories and emotions. Many essential oils have antibacterial, antifungal, and/or antiviral qualities, and contrary to antibiotics, essential oils do not promote resistance.4

Modern scientists are not only finding compelling links between scents and human behavior,5 scents can actually influence the biochemistry of your nervous system.

This was shown in a 2002 Japanese study,6 which found that certain oils would stimulate sympathetic nervous system activity whereas others would calm it. (Your sympathetic nervous system modulates processes such as your heart rate, blood vessel constriction, and blood pressure.)

For example:

  • Black pepper, fennel, and grapefruit oil caused a 1.5- to 2.5-fold increase in sympathetic nervous system activity (as measured by an increase in systolic blood pressure)
  • Rose and patchouli oil resulted in a 40 percent decrease in sympathetic nervous system activity
  • Pepper oil induced a 1.7-fold increase in plasma adrenaline concentration
  • Rose oil caused adrenaline to drop by 30 percent

Lavender and Jasmine Help Uplift Your Mood

A Korean study7 found that lavender reduced both insomnia and depression in female college students.

Another study8 published in Phytomedicine in 2010 found that an orally administered lavender oil preparation (Silexan) was as effective as the drug Lorazepam for the treatment of generalized anxiety disorder. According to the authors:

"Since lavender oil showed no sedative effects in our study and has no potential for drug abuse, silexan appears to be an effective and well tolerated alternative to benzodiazepines for amelioration of generalized anxiety."