Easily recognized by its smell, tea tree essential oil is often used in aromatherapy, though it also offers a number of additional health benefits. Two of its active constituents, 1,8-cineole and terpinen-4-ol, are responsible for so many of the benefits tea tree oil provides. The following offers a quick look at just a few of the top health benefits associated with these two powerful constituents.
1,8-cineole has been shown to act as an analgesic, antispasmodic, and anti-inflammatory agent, while also increasing cerebral blood flow . As a result, it is ideal for fighting headaches caused by tension, as well as decreasing muscular tension in the neck and back.
In addition, 1,8 cineole has demonstrated an ability to help stimulate cell-mediated immune response, although the exact biological actions are not known . This means that it can effectively be used to treat a variety of conditions that can compromise the immune system, including wounds, ulcers, shingles, herpes simplex virus, burns, and cuts. Thanks to the stimulated immune response, the 1,8 cineole found in tea tree essential oil can also speed up the healing process by decreasing the chances of an infection.
A second active constituent, terpinen-4-ol, gives tea tree oil most of its fungicidal properties, which has been confirmed in hundreds of studies that show it can induce damage in the walls of fungus and bacteria . This is why tea tree oil is a common ingredient in products made to naturally treat bacterial infections, cold sores, fungal infections (such as Candida, athlete’s foot, or jock itch), MRSA, and even bad breath.
 http://naha.org/index.php/naha-blog/staying-healthy-using-essential-oils-rich-in-cineole  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2374764/  http://www.ncbi.nlm.nih.gov/pubmed/27388769