A new Harvard study suggests men who eat higher amounts of soy-based foods become “feminized” – confirming a series of reports documented by longtime WND columnist Jim Rutz and drawing outraged protests from the soy food industry.
According to a report from Reuters, the study was done by Jorge Chavarro of the Harvard School of Public Health in Boston, whose work appeared in the journal Human Reproduction.
It reportedly is the largest study of humans to look at the relationship between semen quality and a plant form of the female sex hormone estrogen known as phytoestrogen, which is plentiful in soy-rich foods.
“What we found was men that consume the highest amounts of soy foods in this study had a lower sperm concentration compared to those who did not consume soy foods,” Chavarro told Reuters.
“It was a relatively large difference,” he said.
The researcher said animal studies already have linked eating the plant-derived estrogens called isoflavones with infertility, but that’s not evident in humans yet.
The researchers looked at 99 men who went to a fertility clinic between 2000 and 2006, and their intake of soy-based foods, including tofu, tempeh, soy sausages, bacon or burgers, soy milk, cheese and yogurt.
Chavarro reported men in the highest intake category had 41 million sperm-per-milliliter fewer than men who ate no soy foods, prompting him to suggest soy has a “deleterious effect” on the reproductive system.
According to WebMD, most of the men who visited the Massachusetts General Hospital Fertility Center still had sperm concentrations within normal ranges, but Chavarro said the circumstances could create an impact in a man who already had a low count.
“Now, I’m a health-food guy, a fanatic who seldom allows anything into his kitchen unless it’s organic. I state my bias here just so you’ll know I’m not anti-health food,” he wrote.
“The dangerous food I’m speaking of is soy. Soybean products are feminizing, and they’re all over the place. You can hardly escape them anymore.
“I have nothing against an occasional soy snack. Soy is nutritious and contains lots of good things. Unfortunately, when you eat or drink a lot of soy stuff, you’re also getting substantial quantities of estrogens,” he continued.
“Estrogens are female hormones. If you’re a woman, you’re flooding your system with a substance it can’t handle in surplus. If you’re a man, you’re suppressing your masculinity and stimulating your ‘female side,’ physically and mentally,” he wrote. “In fetal development, the default is being female. All humans (even in old age) tend toward femininity. The main thing that keeps men from diverging into the female pattern is testosterone, and testosterone is suppressed by an excess of estrogen.
“If you’re a grownup, you’re already developed, and you’re able to fight off some of the damaging effects of soy. Babies aren’t so fortunate. Research is now showing that when you feed your baby soy formula, you’re giving him or her the equivalent of five birth control pills a day. A baby’s endocrine system just can’t cope with that kind of massive assault, so some damage is inevitable. At the extreme, the damage can be fatal.”
Many who wrote reflected the same concerns included in a PRNewswire statement from the Soyfoods Association of North America.
The organization called Chavarro’s work a “small scale, preliminary study.”
“This study is confounded by many issues, thus I feel the results should be viewed with a great deal of caution,” warned Dr. Tammy Hedlund, a researcher in prostate cancer prevention from the University of Colorado Health Sciences Center in the Soyfoods Association statement.
“Chavarro’s study conflicts with the large body of U.S. government and National Institute of Health-sponsored human and primate research, in which controlled amounts of isoflavones from soy were fed and no effect on quantity, quality or motility of sperm were observed,” the trade group said.
Read all of Rutz’s columns on soy for the whole story:
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