Yogurt, a food made from milk fermented with beneficial bacteria, has been consumed in many parts of the world for over five thousand years. A variety of health benefits have been attributed to yogurt, some of which have been supported by scientific research, such as the prevention of colon cancer.
Protects Against Carcinogens
A study conducted at the Laboratory of Veterinary Public Health, The University of Tokyo, Japan found that yogurt decreased the number of abnormal cells in the colon. In the study, colon cancer-prone laboratory rats that consumed yogurt for two weeks showed significantly fewer abnormal colon cells. Rats that had been given 1,2-dimethylhydrazine dihydrochloride, a known colon carcinogen, showed significantly fewer colon tumors than control groups that received a non-fermented milk diet. The study was published in the 2010 "Experimental Animals" journal.
Epidemiology
Eating yogurt decreases your risk for colorectal cancer, according to a study by the Department of Health Promotion and Preventive Medicine, Nagoya City University Graduate School of Medical Sciences, Mizuho, Nagoya, Japan. The study followed over 100,000 participants between the ages of 40 and 79 for two years and evaluated the relationship between diet and colorectal cancer deaths. Male study participants who reported eating yogurt had slightly less incidence of rectal cancer, according to the researchers of the study, published in the 2004 "Nutrition and Cancer" journal.
Protects Against Radiation
Probiotics from yogurt protect the colon from radiation damage, according to a study by Ankara University School of Medicine, Ankara, Turkey. In the study, laboratory rats consumed the probiotic Lactobacillus bulgaricus in addition to undergoing abdominal radiation treatment. The researchers examined the rats' lymph nodes, liver and spleen, as well as sections of the small and large intestine eight days after radiation exposure and found evidence of a protective effect of decreased inflammation exerted by the yogurt extract on the intestines. The study was published in the May 2007 issue of "Nutrition."
Inhibits Cancer-Inducing Enzymes
Cancer-inducing enzymes are inhibited by bacteria in yogurt, according to a study at Centro de Referencias para Lactobacilos, Chacabuco Tucumin, Argentina. In the study, published in the April 2005 issue of "Biocell," laboratory mice exposed to the carcinogen 1,2-dimethylhydrazine and fed yogurt showed lower activity of the pro-cancer enzymes beta-glucuronidase and nitroreductase. The study compared the effects of yogurt to unfermented milk and an extract of yogurt that contained no bacteria and found that the yogurt was effective, while the unfermented milk and the bacteria-free extract were not effective at inhibiting colon cancer.
References
- "Experimental Animals"; Inhibitory effect of yogurt on aberrant crypt foci formation in the rat colon and colorectal tumorigenesis in RasH2 mice; Narushima S, et al.; 2010
- PubMed.gov: Diet and colorectal cancer mortality: results from the Japan Collaborative Cohort Study
- PubMed.gov: Effects of probiotics on radiation-induced intestinal injury in rats
- PubMed.gov: Reduction of beta-glucuronidase and nitroreductase activity by yoghurt in a murine colon cancer model
