fresh oregano close-up.
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Oil of oregano comes from a plant that is in the same family as the herbs mint and basil. Like other essential oils, it has anti-bacterial, anti-viral and anti-fungal properties. There is no evidence to show that oil of oregano can discriminate between harmful bacteria and healthy probiotic bacteria in your body. As with antibiotics, this natural plant oil can lower your levels of good bacteria and cause some side effects.

Oil of Oregano Benefits

Oil of oregano has been traditionally used to alleviate symptoms of respiratory illness, indigestion, dental cavities, arthritis and urinary tract infections. This medicinal plant is used for its anti-pathogen and antioxidant properties. Research published in 2007 in the "Pakistan Journal of Botany" concluded that oil of oregano was able to destroy several types of bacteria including salmonella, typhi and e.coli bacteria. Unlike antibiotics, this plant oil also acts against viral and fungi infections. However, further research is needed to assess how effective oil of oregano is against infections and how much is needed.

Probiotic Effects

Probiotics are "good" bacteria that aid your digestion and help keep the growth of harmful bacteria, viruses and fungi at bay. Research published in the journal "Cellular Microbiology" in 2008 documented the effects of probiotics on promoting cancer cell death. In an animal study also published in 2008 in the journal "Vaccine," researchers found that probiotics enhanced the effects of a vaccine against the human rotavirus, which causes severe diarrhea in infants and children. When populations of healthy probiotic bacteria are diminished or destroyed due to diet, medications or natural anti-bacterial effects, your body may be more susceptible to infections from harmful organisms.

Allergic Reactions to Essential Oils

Oil of oregano and other essential plant oils may be natural, but they can still cause potent effects and reactions in some cases. A 1996 study published in "Annal of Allergy, Asthma and Immunology" found that some individuals had an allergic reaction to oil of oregano and several other plant oils. These effects were seen during a scratch test when the essential oils were applied on the skin, however oil of oregano can cause a reaction if taken orally or inhaled, in some cases.

Considerations and Use

The effects of oregano oil are typically not as potent as antibiotics against any type of bacteria. This means that using this oil may not be enough to stem the growth of an infection on the skin or in the body. Consult your doctor if you have any type of infection. Additionally, read the label of any essential oil carefully to ensure that it is for internal use and use only as directed.