Dear Umbra,

As a practicing vegan for quite some time now, I take pride in my knowledge of nutrition and my ability to enrich my body through a varied diet with all the essentials. For the past five years or so, I have heavily relied on soy products for protein and other nutrients. Recently, however, I have heard that soy products increase estrogen levels, which in turn increase the risk of cancer (specifically breast cancer). I also have been told to stay away from soy because so many people are allergic to it.

I always thought soy was great and that soy protein even decreased the risk of cancer. So what is the real deal? Can I be cow- (and earth-) friendly by drinking soymilk without increasing my risk of breast cancer?

St. Louis, Mo.

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Dearest Cassandra,

My editor, whose every whim is my command, finds your question sympathetic and has pressed upon me to answer it. She, too, consumes great quantities of the soybean (glycine max) and has become concerned lest doing so compromise her health and her ability to compete in triathlons.

Are these soybeans good for you?
Is this even an environmental question?

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You both have turned to the environmental advice columnist for assistance in understanding the health implications of soy, but I ask: Is this an environmental matter? We should definitely resolve the question of whether too much soy increases the risk of breast cancer before continuing to OD on the stuff, but how does this dietary quandary relate to the well-being of the planet? (For that matter, how does it relate to the well-being of cows? Whether it’s better to never have been born or to live your whole wretched life in a conventional dairy operation is something of an unplumbable bovine existential mystery.) You do reference the environment at the end of your letter, but is drinking soy milk truly an eco-friendly act? Fewer cows is definitely a good thing for the earth, but your beverage of choice might not be, if it is made from some of the approximately 80 percent of the U.S. soy crop that is genetically modified, or the even larger amount that is heavily treated with dangerous chemicals. (I will concede, however, that soy milk holds the environmental advantage over cow’s milk in being lower on the food chain.)

I raise the “environment=health?” question and hold inquisitive Cassandra up for example because so many of you dear readers have written similar letters about health concerns, and I want to know the general opinion of Gristians on this topic. Where is the line between a health concern and an environmental concern? People often make environmentally beneficial choices out of concern for their own health rather than out of some altruistic idea of planetary rescue, so it is certainly useful to play the health harp if one wants to convert pollutocrats. I’ve often answered your health questions on that basis, providing you with the tools to go forth and sway the masses. Yet this straight-up query about the current medical opinion on the health effects of soy consumption seems to fall outside the eco-boundary.

Please join my debate with my editor: Write in and let me know your thoughts on this question. Does Cassandra’s concern fall under my mandate as an environmental advice columnist? I eagerly await your opinions.


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