Just a few days of walking and eating healthy plant foods can lower the level of the cancer-promoting growth hormone IGF-1 enough to reverse cancer cell growth in a Petri dish. This is detailed in my last three blog posts Cancer-Proofing Your Body, Treating an Enlarged Prostate With Diet, and How do Plant-Based Diets Fight Cancer?
We know decreasing animal product consumption decreases our IGF-1 levels, but how low do we have to go? How plant-based does our diet need to get? In my 2-min. video How Plant-Based to Lower IGF-1? the IGF-1 levels are compared between men and women eating conventional, vegetarian, and vegan diets. Only the vegans had significantly lower levels.
Vegan men tended to have significantly higher testosterone levels than both vegetarians and meateaters (see graph here), which can be a risk factor for prostate cancer, the reason plant-based diets appear to reverse the progression of prostate cancer may be due to how low their IGF-1 drops (see Cancer Reversal Through Diet?).
Boosting cancer defenses within just days of eating healthy is a remarkable finding. For those interested in the whole story, I started out introducing Nathan Pritikin and the elegant series of experiments that became part of his legacy.
Researchers were able to demonstrate the mechanism by which a plant-based diet and exercise could suppress the growth of breast and prostate cancer cells and protect against prostate enlargement (more on prostate problems in Some Prostates are Larger Than Others and Prostate Versus Plants).
I also asked and answered Is It the Diet, the Exercise, or Both?
Finally, for those interested in whether lower levels of growth hormones in vegans might interfere with the accumulation of muscle mass, see my 3-min. video Plant-Based Bodybuilding.
-Michael Greger, M.D.
Image credit: edwick / Flickr