When essential oils make their way into your body, they have an impact on your olfactory system, the system relating to smell, and limbic system, which is your “emotional brain.”
When you inhale, molecules from the essential oils make their ways to the brain. When they get to the brain they have an effect on the amygdala, which is part of the limbic system and known as the emotional center of the brain.
Essential oils are also known to work through the olfactory system to cause the brain to secrete neurotransmitters, such as dopamine and serotonin, which can elevate mood. Not only are these neurotransmitters needed to make you feel calm and relaxed, but serotonin is also needed to produce melatonin, the hormone responsible for making you feel sleepy at bedtime.