Wednesday Bubble: the soy controversy

Posted by Liz on Apr 7, 2010 in bone health, emotions, hot flash | 0 comments

Do they or don’t they?

Soy isoflavones have been touted as beneficial in everything from improving body composition and lowering breast and colorectal cancer, to addressing menopausal hot flashes and moods. You can read about some of these findings on Flashfree. This week, Reuters Health reported that eating foods rich in soy protein (i.e. 25 grams of soy protein and 60 mg isoflavones) daily did not provide favorable responses from blood fats, implying that soy has little benefit in terms of lowering cholesterol levels and in turn, promoting heart health.

Are you confused yet?

Increasingly, women are turning to soy and other compounds as alternatives to estrogen and hormone replacement therapy, which mounting evidence shows can be associated with a broad range of risks including  increased breast, lung and ovarian cancer to heart disease. And yet, findings from clinical trials examining soy are often contradictory, making it difficult to come to any firm conclusion about its benefits.

What’s the problem? Well, researchers say that part of the problem is poorly designed studies, small number of study participants, wide range of ages and years from menopause, studies that don’t examine the pros and cons of an agent or strategy for a long enough period of time (i.e. longer than a year). In other cases (as I’ve argued previously), the study design does not account for certain factors that are critical to a therapeutic strategy, for example, the opportunity to clearly focus an intervention so that individual factors are accounted for (this was borne out by findings from a trial that examined and provided evidence for the role of acupuncture in easing hot flashes).

There’s good news though! Researchers finally appear to be getting their act together on the soy fron. They’ve announced that they are conducting a well-designed, large trial of soy phytoestrogens. Called  SPARE (Soy Phytoestrogens as Replacement Estrogen), this new study will be looking at the effects of 200 mg soy versus sugar tablet daily — namely on bone health and symptoms —  in 248 menopausal women over a two- year period. They will also be taking daily calcium carbonate plus vitamin D (in ranges of 500 mg to 1000 mg calcium and 200 to 400 IU vitamin D, depending on previous intake).

The study is specifically geared towards looking at spine bone density, but will also be looking at hip density, thyroid levels, menopausal symptoms, mood changes, depression, and quality of life, as well as any changes in blood fats. Study participants are between the ages of 45 and 60 and are within five years from menopause. What’s more, the researchers have also included a large percentage of hispanic women, which allows them to focus on how soy affects this minority group (Notably, the large multiethnic population of women in this study includes Asians, Blacks and Caucasians.)

The researchers say that they hope that the results of SPARE will provide a range of information that is especially relevant to Boomers reaching menopause. They also note that the dose of soy isoflavones being studied is much larger than what’s been studied in previously and are roughly twice that typically consumed in the Asian diet.

I realize that this post is pretty scientific. But what makes it most relevant is that it appears that researchers are finally starting to design studies that might actually show benefit of some of the alternative strategies we have available to us on the market. For those of you who insist on calling these alternatives “snake oil,” all I can say is ‘stay tuned.’

This bubble might finally be shattered; perhaps all that is needed is a better understanding of what it needs to test these substances appropriately.