I regularly get the question whether it is useful to smell an essential oil, because then it does not work right?
It does a lot. The molecule of the essential oil can have a lot of influence, from your emotional state to your lifespan. The molecule of the oil is inhaled and ends up at the olfactory epithelium in your nasal cavity. There are approximately 2000 receptors connected to this small epithelium in your nose, which allows you to recognize different odors. The collection system where all these receptors come together (the Bulbus Olfactorius) sends the impulses that come through from your nose to the central nervous system of your brain. This nervous system is connected to the Gustatoric center where your taste is determined, it is connected to the Amygdala where your emotions are stored and it is connected to the Gyrus Hippocampi where the limbic system is located. The limbic system regulates your feelings, emotions and moods. In addition, the limbic system is also connected to the Hypothalamus which has control over heart rate, blood pressure, respiration, memory, stress level and hormone balance.
Our sense of smell is the only organ directly connected to the limbic system. A scent can evoke memories of us before we are aware of it. Just think of the smell of apple pie, the smell of your grandmother or grandfather, the scent of Christmas etcetera. You first respond to the smell and think later about the origin of this scent. All of our other organs (touch, taste, hearing and vision) are not connected to the hypothalamus, but to the thalamus which more dominates our rational mind.
The hypothalamus is one of the most important parts of our brains. It regulates our hormonal system and delivers signals that regulate many functions of our body. It affects our growth hormones, sex hormones, thyroid hormones and neurotransmitters such as serotonin (the happiness hormone).
In this way an essential oil has a very large effect on our body (physical and emotional) when we just breath it in.