Wednesday Bubble: close to the bone

Posted by Liz on Jul 15, 2009 in bone health | 0 comments

Let’s be honest; bone loss is a natural part of aging.

As I’ve written previously, women are at particularly high risk for bone loss as they age because of declining estrogen levels, and in turn, a reduced ability to prevent an increase in net bone resorption (or bone loss due to the activity of bone cells). Although isoflavones (plant derived compounds with estrogen-like properties) have been reported to protect bone from deficiencies in estrogen, there have been little data that show that they can specifically influence resorption.

Hence, I was interested in a small study published in the online edition of the Journal of Clinical Endocrinology & Metabolism examining of four different types of isoflavone supplements on bone resorption. In it, researchers compared supplements containing the isoflavones soy cotyledon (derived from the leaf coating around the seed of the soybean), soy germ (the embryo of the soybean), kudzu and red clover to 1 mg estradiol plus 2.5 mg medroxyprogesterone or 5 mg/day of the anti-osteoporosis agent Actonel®.

Study findings showed that the hormones plus progesterone or Actonel significantly decreased net bone resorption by as much as 22% and 24%, respectively. In comparison, only soy isoflavones derived from the cotyledon and germ had a significantly modest effect on reducing bone resorption (by 9% and 5%, respectively), while kudzu and red clover did not.

Clearly, this study, while small, shows that isoflavones can help to prevent bone loss during menopause. However, not all isoflavones are created equal, and source appears to as important as insuring that the product is standardized and manufactured in a licensed facility. What’s also notable about this study is that the researchers did not examine whether or not ingesting the specific isoflavones via food sources would have an equally beneficial effect.

Because it can be difficult to discern which products contain which types of isoflavones and the amounts, it’s best to speak to a nutritionist or a naturopath before supplementing your diet. No bones about it though; the results are promising enough to warrant further study.

What steps are you taking to prevent bone loss as you age? And if you use soy, in what forms are you taking it?