Does Flaxseed Help Lower Risk

QUESTION: Does flaxseed oil help with the prevention of breast cancer? If yes, how? How much should one take for it to be effective?

ANSWER: Flaxseed contains a high concentration of lignans, which can act like very weak estrogens. The theory goes like this: If your body sees these weak estrogen-like substances instead of your own body's strong estrogen, then the bottom line is less estrogen effect on your body's tissues. This may be particularly important for breast tissue, which likes estrogen around and tends to grow in response to it. Keep in mind that this is theory. It remains unproven, even though you will find many people having many strong ideas about this. On the other side of the fence are those who think that it's a bad idea to add any estrogen-like substances into your body. They think it's best to avoid anything, in whatever form, that might stimulate growth of breast tissue. Flaxseed also contains fiber and alpha-linoleic acid, an omega-3 essential fatty acid, which helps lower cholesterol.

A tablespoon a day is what the proponents suggest; "none" is what the concerned folks would tell you. Because this is a tough one to study, we might never come to the "right" answer on this, at least no time soon.

—Marisa Weiss, M.D.