Men eating a vegan diet have lower levels of a protein associated with prostate cancer, British scientists said today.
Saying that while further research was needed, the findings from researchers at the Imperial Cancer Research Fund in Oxford suggest that a diet without meat or dairy products could reduce the risk of contracting the deadly disease.
The role of IGF-I and Cancer
Previous studies have shown that high blood levels of IGF-I -- an insulin-like growth factor -- appear to play a key role in promoting the growth of prostate cancer.
The study, conducted at Oxford using 696 British men, found IGF-I levels were nine percent lower in vegans than meat-eaters, and seven percent lower than in vegetarians.
Published in the British Journal of Cancer, researchers also reported that previous studies have found prostate cancer rates lower in countries with low consumption of meat and dairy.
In Great Britain, prostate cancer is the second most common cancer, killing approximately 9,500 men with about 21,000 new cases are diagnosed each year.
IGF-I Also a Factor in Breast Cancer
The findings reinforce a sobering study published in May of 1998 in the medical journal Lancet. This study, conducted by Susan Hankinson, Sc.D., showed a strong relationship between IGF-I levels and breast cancer.
Thousands of women enrolled in the Harvard Nurses' Health Study gave blood samples in 1989 and 1990. In 1998, Dr. Hankinson's team identified 397 of these women who had subsequently developed breast cancer. Tests from the 1989 blood samples then revealed that those women with high IGF-I levels in their blood had up to 5 times the risk of developing breast cancer than those with low IGF-I concentrations.
If consumption of meat and dairy is associated with increased levels of free IGF-I in the bloodstream, as the new Oxford study appears to show, the public now has valuable information for combatting and helping prevent breast and prostate cancer -- eat a vegan diet.
Biotechnology and IGF-I
During the late 20th Century, Monsanto Corporation introduced a substance which can be regularly injected into dairy cows in order to increase milk production. Called Recombinant Bovine Growth Hormone (rBGH), it also increases the amount of free IGF-I in milk from treated cows. There is disagreement about whether the consumption by people of IGF-I found in cows' milk, identical to human IGF-I, increases IGF-I levels in people, or whether protein found in cows' milk is responsible.
But dairy product consumption has been shown to increase serum concentrations of insulin-like growth factor (IGF-I).
Take Home Message
Additional research should be conducted immediately using vegans in the US to compare against meat and dairy consumers. It may be that the differences in IGF-I levels are even higher in the US than the UK, since Europe and Canda and other parts of the world have rejected the rBGH technology widely used in the US and deemed "safe" by FDA regulators using conclusions from Monsanto studies.
Meanwhile, there would appear ample evidence, for those concerned about breast and prostate cancer, to greatly reduce and elmininate meat and dairy products -- no matter what part of the world you live in.
After all, we can hear those ravenous cancer cells begging now to be fed so they can grow and spread, and here's what they're saying:
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