Researchers Wake Forest University Baptist Medical Center recently reported on the effects of long-term consumption of a diet rich in soy isoflavones on male monkeys, finding that such a diet had adverse effects on the monkeys.
Published in Hormones and Behavior, the study found that,
In the monkeys fed the higher amounts of isoflavones, frequencies of intense aggressive and submissive behavior were elevated. In addition, the proportion of time spent by these monkeys in physical contact with other monkeys was reduced by 68 percent, time spent in proximity to other monkeys was reduced 50 percent and time spent alone was increased 30 percent.
. . .
To the best of our knowledge, the present study may be the first to demonstrate that long-term consumption of isoflavones can alter patterns of agnostic and social behavior in primates. The present findings suggest that careful attention will be required to balance beneficial and potentially adverse effects.
Certainly animal rights activists are going to jump on this and I might as well get out in front of them — I can’t think of anything much crueler than forcing monkeys to eat a soy-heavy diet. Yuck. The next thing you know, they’ll be trying to force vegan food on cats and dogs.
In male monkeys, too much soy has adverse effects. Press Release, Wake Forest University Baptist Medical Center, April 30, 2004.