Parasites affect millions of North Americans — even those who never travel. They are organisms that live within the intestinal tract, growing and feeding off the body. They may be visible (like tapeworms and pinworms) or microscopic (like Giardia lamblia). While almost any persistent digestive disorder could result from a parasite infection, the most common symptoms are diarrhea and abdominal pain. Other symptoms include nausea, vomiting, gas and bloating, foul-smelling stools, weight loss, headache, constipation and fatigue. Then again, some infected people have no symptoms.

According to Cass Ingram, author of The Cure is in the Cupboard, compounds in oil of oregano (especially carvacrol and thymol) have strong antiparasitic properties and have been used with success in neutralizing various parasites. A recent study confirms Ingram’s assertion.

Health Explorations Trust in Arizona and Biotics Research Corporation in Texas conducted a joint study to test the efficacy of oil of oregano on intestinal parasites. In this study, 14 people, who all tested positive for various parasites, were given 600 mg emulsified oil of oregano daily for six weeks.

At the end of the trial, the researchers noted the complete disappearance of one parasite, Entamoeba hartmanni, in four cases, Endolimax nana (which can cause hives) in one case, and Blastocystis hominis in eight cases. This common parasite has been associated with irritable bowel syndrome, infective arthritis and intestinal obstruction. Blastocystis hominis scores also declined in three additional cases. Furthermore, gastrointestinal symptoms improved in seven of the 11 patients who had tested positive for Blastocystis hominis.

Sources: Phytother Res. 2000 May;14(3):213-4; Great Smokies Diagnostic Laboratory (www.gsdl.com)