The two main varieties are origanum vulgare and thymus capitatus.

According to HealthNews.com:

The lead ingredient in oregano oil is carvacrol, a strong antimicrobial used to preserve food and protect against mold and other common bacteria, making it the largest healing agent of the oil. Thymol is the second most active ingredient important as a fungicide and is the leading bad-breath killing agent in the popular mouthwash Listerine, capable of preventing tissue deterioration and promoting growth. The rest of the ingredients provide more antibacterial support, prevent the damage caused by free radicals, act as allergen-blockers, and inhibit the growth of cancer cells.

Make sure to find a supply that contains the right stuff, because the regular off-the-shelf stuff doesn’t use the two varieties of herb mentioned above, and does not provide the healing properties and are not good remedies for bad breath.

This remedy might produce allergic reactions, so take note of the precautions in the original article.

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