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Chlorophyllin Reduces Aflatoxin Indicators Among people at High Risk for Liver Cancer


Study Shows Chlorophyllin Intervention Could Prevent Some Environmental Cancers

A study conducted by researchers at the Johns Hopkins Bloomberg School of Public Health shows that taking chlorophyllin greatly reduces the levels of aflatoxin-DNA damage byproducts in the body, which are indicators of exposure to carcinogenic aflatoxins and increased risk of liver cancer. Chlorophyllin is a derivative of chlorophyll and is used as an over-the-counter diet supplement and as a food colorant. The results appear in the November 27, 2001 edition of Proceedings of the National Academy of Sciences.

"Our study shows that taking chlorophyllin three times a day reduced the amounts of aflatoxin-DNA damage by 55 percent, compared with taking a placebo," says Thomas Kensler, PhD, professor of environmental health sciences at the Johns Hopkins Bloomberg School of Public Health. "Taking chlorophyllin or eating green vegetables, like spinach, that are rich in chlorophyll may be a practical way of reducing the risk of liver cancer and other cancers caused by environmental triggers," explains Dr. Kensler.

Dr. Kensler and his colleagues conducted a double-blind study among residents of Qidong, China. The people of the region have an extraordinarily high rate of liver cancer, which is due in part from routinely eating foods contaminated with carcinogenic aflatoxins. The aflatoxin is produced by molds found in foods like corn, peanuts, soy sauce, and fermented soybeans. For the study, researchers recruited 180 healthy adults. Half of the group was given 100 mg tablets of chlorophyllin to take three times a day with meals for four months. The other half was given a placebo. Urine and blood samples were taken over four months to determine the effects of chlorophyllin on excretion of aflatoxin-DNA damage products.

According to the study's results, the people who took chlorophyllin showed a 55 percent reduction in aflatoxin-DNA damage, compared to the placebo group.

"Studies conducted by our co-author, George Bailey of Oregon State University, have suggested that chlorophyllin acts as an 'interceptor molecule' to block the absorption of aflatoxins and carcinogens in the diet," explains John Groopman, PhD, professor and chairman of the Department of Environmental Health Sciences at the Johns Hopkins Bloomberg School of Public Health. "Our study shows that chlorophyllin can effectively reduce aflatoxin levels, which should reduce the risk of liver cancer. Since chlorophyllin is found in many foods or can be easily added to the diet, it could be a safe and effective prevention method. The study adds to the evidence that green vegetables contain effective anticarcinogens," adds Dr. Groopman.

Follow up studies are planned to determine whether this early protective action of chlorophyllin extends to either delay the onset or reduce the incidence of liver cancer.

Patricia Egner, Jin-Bing Wang, Yuan-Rong Zhu, Bao-Chu Zhang, Geng-Sun Qian, Shuang-Yuan Kuang, Stephen J. Gange, Lisa P. Jacobson, Kathy J. Helzlsouer, George S. Bailey, John D. Groopman, and Thomas W. Kensler assisted in the research and writing of the article "Chlorophyllin intervention reduces aflatoxin-DNA adducts in individuals at high risk for liver cancer."

The study was funded by grants from the U.S. Public Health Service, National Institute of Environmental Health Sciences.

Public Affairs Media Contacts for the Johns Hopkins Bloomberg School of Public Health: Tim Parsons @ 410.955.6878 or