To Bean or not to Bean…..

I recently returned from Japan where I consumed a lot of soy, which made me think about how many of my patients have asked me about whether soy is good or bad for health. Some of my patients have heard or read that soy is “good” and so consume a lot of it.

The fact is, whether eating soy and soy products is good or bad for our health depends on which research studies you read. However there are some facts you can ponder.

Soy plants contain “phytoestrogens”, or plant based estrogens, which in theory can affect our bodies the way that our own endogenous estrogens, or synthetic estrogens can.

Some studies seemed to show that intake of soy could block the effect of our own estrogen by attaching to estrogen receptor cells in the breast, thereby reducing the growth of estrogen sensitive breast cancers. However a recent study in the Journal of Cancer Prevention Research casts doubt on this theory. Some studies have shown that menopausal hot flashes are reduced for some, but not all people taking soy supplements.  A POSSIBLE link between soy and increased cognitive impairment in older people has also been observed, but other research has come to the opposite conclusion.

So what is a person to do ? So much that I advise patients about always comes back to what I call the “Goldi Locks Principle”.  Not too much, not too little. Everything in moderation.

I always have new patients keep a food journal for a week. One of my patients who came for help with irregular periods recorded that she had soy milk on her cereal for breakfast every morning, followed by soy yogurt for a mid morning snack, and frequently ate soy cheese as an evening appetizer.  She liked cheese and thought soy would be better than dairy based cheese.

I would say this is probably too much to have everyday, especially since the above products may contain a lot of “processed soy” which contains large amounts of soy “isoflavones” that may be a culprit in some of the possible negative effects of soy.

There may be something about whole soy beans and fermented soy that is healthier for us than soy supplements or soy isoflavones. So unless your physician advises you to avoid all types of soy for a specific reason, you should enjoy edamame (whole soy beans), tofu (preferably pickled or fermented), tempeh (a form of fermented soy), and miso (fermented rice, barley, and soy combined).  Maybe just not three servings per day, seven days per week.