Skin
Depending on the oil, the amount it is diluted, and the application technique, the absorption of essential oils through the skin varies. Essential oils are minutely absorbed through the skin; a higher concentration of oil will absorb at a higher rate than a more diluted oil. Different areas of the skin are more permeable than others, like the palms of hands, soles of feet, forehead, scalp, behind the ears, inside the wrists and armpits, and will be quicker to absorb oil compared to areas like the legs and stomach areas. Most oils should be diluted when used directly on skin to avoid any possible adverse reaction. Some people may use a mild essential oil such as Lavender directly on their skin, however the safe method is always to dilute the highly concentrated oils.
Glandular
When essential oils are inhaled, the molecules travel through the olfactory system into the limbic system of the brain. The oils are absorbed through the nerve pathways from the sinuses to the limbic system’s central glands. A simple whiff of the right essential oil can stimulate the emotional, neurological, and immunological parts of the mind and body.
Respiratory
When inhaled, the aromatic molecules of the essential oil travel into the lungs where they are absorbed into the bloodstream. Aromatherapy often uses oils that not only promote calmness and relaxation, but also medicinal benefits that have a direct effect on the sinuses, throat, and lungs. Many essential oils specifically aim to offer relief for many respiratory issues.
Circulation
Essential oils can be used both topically and through inhalation to boost circulation all over the body. Improving circulation treats a number of ailments, from cold hands and feet, to poor skin tone, to liver function, to reducing blood pressure and preventing clots. The use of essential oils for circulation is a natural way to stimulate blood flow and, when used in combination with massage, can enhance the circulation stimulating effects the massage provides.