Population Studies Show Miso Is a Potent Medicine
Although Ito's radiation studies were very impressive, it was large, long-term population studies in Japan that began in the 60's and 70's and were published in the 80's that first alerted researchers to miso's potential as a potent medicinal food. One study of over a quarter of a million men and women showed that those who ate miso soup every day had fewer cases of certain types of cancer. The study also showed much lower incidents of coronary heart disease, liver cirrhosis, cerebrovascular disease, and peptic ulcers among those who ate miso soup. At first researchers associated the lower cancer rates with the orange and yellow vegetables that are traditionally cooked into miso soup and are known to have their own health benefits. However, in the late 80's a team of medical researchers at Tohoku University, Japan, discovered an ethyl ester, a fatty acid that is produced by the breakdown of complex fats during miso's fermentation, that acted as an anti-mutagen. The results of this work, which were presented to the Japan Agricultural Society, were extraordinary, because they showed that ethyl ester was only made during fermentation. They also scientifically demonstrated that the small amounts of ethyl ester found in a bowl of miso soup could cancel the effects of large amounts of nicotine and burnt meat mutagens. Another population study conducted by the University of Alabama at Birmingham compared the breast cancer rates among first generation Japanese immigrants to Hawaii with subsequent generations of Japanese in Hawaii. The study showed a forty percent higher rate of breast cancer in the subsequent generations. Researchers theorized that miso, natto, soy sauce, and other fermented soy foods may have been responsible for the lower cancer rate among the first generation immigrants. The consumption of these foods in Japan is about five times more than the amount consumed by Japanese immigrants to Hawaii.