The main benefits of oregano oil may include the treatment of colitis, fighting candida and protection against some bacteria, explains About.com. There is very limited research available on oregano oil, and only preliminary tests have been done on the effectiveness of this substance.
Research has shown that a combination of oregano and thyme oil may relieve colitis, according to About.com. Scientists, who did the experiments on mice, found that this combination of oils showed a significant decrease in inflammation following treatment; however, human trials have not been done as of early 2015, so conclusive evidence is not yet available.
It has also been found that oregano oil may help to fight the growth of the yeast, Candida, claims About.com. This yeast normally lives in the body, but it often triggers infections such as thrush. As with colitis, studies have been done on animals and in test tubes, but no human trials have been attempted.
A number of studies of oregano oil have also been done to look at the antibacterial properties of the substance, notes About.com. There were studies done in 2004 and 2005 on mice, which concluded that oregano oil may work against certain bacteria, such as those that cause dysentery.