I just showed you why I think you can eat soy in moderation. This is especially true for men who have prostate cancer. That is because a new study says soy can stop the spread of prostate cancer.
In this study, the researchers found that genistein, a phytoestrogen in soy, almost completely eliminated the spread of prostate cancer to the lungs in mice. The amount of genistein they used was no more than what you might easily get in your diet. This was the first study to demonstrate that genistein can stop prostate cancer spread.
However, its not the first study this research team has done on soy and prostate cancer. Senior researcher Raymond Bergan and his team showed in a previously study that genistein stops cancer cells from detaching from a primary prostate tumor. It also represses cell invasion. However, that study was in a lab dish.
In this live animal study, Dr. Bergans group fed genistein to several groups of mice. Then they implanted them with an aggressive form of prostate cancer. Genistein did not reduce the size of tumors that developed within the prostate. However, it stopped lung metastasis by a whopping 96%. They repeated the experiment and found the same result.
Dr. Bergan cautioned that much is unknown about the use of genistein in preventing cancer spread. For example, longterm use may be more powerful than a recent start-up.
Its true that other studies have associated a greater soy intake with less prostate cancer death. However, Dr. Bergan cautions that they are just an association. They do not prove anything. And this study did not follow cell death, just the spread of tumors.
I do think that soy and its isoflavones (phytoestrogens) have a huge role to play in health, including osteoporosis, heart disease, and cancer prevention and treatment.
Does it help everyone? Nope. And neither does any single supplement help everyone with a particular problem. That said, I think that fermented soy food products are indeed a health food. The jury is still out on tofu. But please feel free to eat miso and tempeh (fermented soy) in moderation. A bit less tofu until we know more (1-2 times a week). And make sure its always organic soy. You definitely want to avoid toxic GMO soy.
If you have prostate cancer, you might try genistein (1,000 mg daily). Its available from your local health food store or online.
Ref: Cancer Research, March 15, 2008.