Some male bodybuilders claim that cabbage as well as broccoli effectively neutralizes estrogen levels. Let's steps back for a minute and ask if this is true,
and can anyone benefit by eating more of these foods?
Well, it is obvious why male bodybuilders find great interest in diminishing estrogen levels in their body. In men, estrogen is believed to be responsible for initiation of prostate cancer, gynecomastia ("man-boobs"), water retention and the urge to buy a smart little outfit. Yech! Not good for bodybuilders. In women, an association has been made between having too many of the wrong kind of estrogens - called 16-hydroxy estrogens - and breast cancer.
Wherecruciferous vegetables are concerned, these claims from bodybuilders may be partially correct. Scientists have shown that cabbage, broccoli and other cruciferous vegetables are rich in an estrogen-fighting chemical called indole-3-carbinol. As this chemical breaks down, another is derived that has much the same effect diindolylmethane (DIM). Apparently, these chemicals boost liver enzymes that neutralize 16-hydroxy estrogens by converting them to weaker 2-hydroxy estrogens, which basically means they zap nasty estrogens.
In a 1997 study on this subject, J.J. Michnovicz et al. (Journal of the National Cancer Institute, 89:718-23) gave female and male test subjects indole-3-carbinol as a supplement (400 milligrams [mg] daily to the women; 500 mg daily to the men). Follow-up testing showed that "bad" estrogens were lessened; "good" estrogens appeared to increase. It's possible to conclude from this that indole-3-carbinol may benefit men and women alike.
It's not a far cry to say that cruciferous vegetables themselves (which are rich in indoie-3-carbinol) could also lower estrogenic activity in your body if you eat enough of them. You'd have to consume a vast amount of cruciferous vegetables to reach the 400 or 500 mg per day mark for indole-3-carbinol, as the human diet normally contains only 25-100 mg per day. However, other coirmounds in cruciferous vegetatales may pick up some of the slack. H.L. Bradlow and colleagues have reported similar estrogen-fighting effects for brassinin, also found in cruciferous vegetables. A variety of such phytochemicals, in amounts you can get from eating cruciferous vegetables, may act together to neutralize estrogens.
Not everyone is thrilled with the idea of eating hearty portions of broccoli, cabbage or Brussels sprouts on a regular basis. For people such as former President George Bush who disdain cruciferous vegetables, indole-3-carbinol and DIM are now widely sold in pill form. For example, DIM is available in an absorbable form in the supplement Di-lndolin. The dosage recommended by the manufacturer is one 100 mg tablet per 30 kilograms of bodyweight - about three tablets (300 mg) per day for a 200-pound bodybuilder. If you take indole-3-carbinol (also available in stores and on the Internet), stick with 400-500 mg per day used in the Michnovicz research.