NEW YORK (Reuters Health) Oct 20 - The spice that lends its brilliant yellow-orange color to mustard, curry powder and other foods could ward off potentially life-threatening infections with Clostridium difficile, according to research presented this week at the American College of Gastroenterology's annual meeting in San Antonio.
"For the last 2000 years people have been using curcumin and we haven't found bacteria resistant to it," Dr. Rattan Patel of the Cedars Sinai Medical Center/VA Medical Center in Los Angeles, who conducted the study, told Reuters Health. Curcumin is found in turmeric, a spice commonly used in Indian cuisine; it's also a U.S. Food and Drug Administration-approved food coloring agent.
Dr. Patel and his team found that extracts of regular grocery-store turmeric inhibited the growth of C. difficile in vitro, at concentrations that would be easily obtained in the colon by adding the spice to food or consuming it in capsule form.
C. difficile is resistant to many commonly used antibiotics; one treatment approach now being tested involves transplanting feces from a healthy person into the ill person's colon in order to restore normal bacterial balance. But the new study suggests that turmeric could help prevent these infections in the first place.
Dr. Patel said in an interview that he undertook his study after researchers from Singapore reported that Indian patients had the lowest rates of C. difficile infection.
Working in the laboratory of Dr. Sydney Finegold, Dr. Patel and his colleagues tested different formulations and concentrations of curcumin against 21 strains of C. difficile. Growth of all of the strains was inhibited by curcumin at a concentration of 128 mcg/mL.
By giving people up to 4 g/day of curcumin, Dr. Patel said, it's possible to obtain a concentration of curcumin in the stool well above the concentrations that inhibited C. difficile growth. In regions where curcumin is a regular dietary ingredient, he added, people typically consume 2 to 4 g/day, and up to 12 g/day can be safely consumed.
Dr. Patel said he is now working with UCLA to develop a clinical trial to test curcumin for preventing C. difficile infection. He expects he would need about 500 patients for each arm of the study, which would mean collaborating with other hospitals to find enough patients.
Key questions that still must be resolved, he added, include figuring out whether curcumin affects the absorption of other medications, and whether it would be best to use the spice in capsules or as a food additive.