Posted on 10/31/2008 8:09:31 AM PDT by Oyarsa
A study recently published in Human Reproduction demonstrated that intake of soy foods significantly reduces sperm counts in men.
The study is especially significant because it is the largest study in humans to examine the relationship between semen quality and phytoestrogens (plant compounds that can mimic the physiological effects of the endogenous hormone, estrogen).
Dr. Jorge Chavarro of the Harvard School of Public Health and his colleagues found that men who ate the most soy food had 41 million sperm per milliliter less than men who did not consume soy products. The normal sperm concentrations for men ranges between 80 and 120 million/ml.
The association between soy food intake and sperm concentrations was even stronger in men who were overweight or obese, and 72% of study participants were. They also found the relationship between soy foods and sperm concentration was strongest in men with “normal or high” sperm counts.
Animal studies have linked the high consumption of isoflavones with infertility, but until now there has been little evidence of this effect in humans. Isoflavones are plant compounds with estrogen like effects and are found mainly in soybeans and soy-derived products.
What is particularly revealing is that the men in the highest intake group (who had the largest sperm count reduction) had a mean soy food intake of only half a serving per day. This is equivalent to having one cup of soy milk or one serving of tofu, tempeh or soy burgers every other day!
(Excerpt) Read more at thehealthyskeptic.org ...
estrogenetic effects also contribute to man cans
real men eat spamalope burgers
You’re right. He doesn’t need soy products—so why take the risk!
aack.
my eyes!
It’s funny you mention broccoli. I generally use an anecdote to explain what you’ve just said. Primitive man wasn’t walking along in the forest one day while hunting and said, “hey that looks good”, and then take a bite. Same with cauliflower. These are man cultivated veggies that were not a part of our diet until recently. Why people don’t understand that man walked the earth for 10000 generations in good health for most of his life while eating fruits and nuts during the day (carbs and sugar for energy while hunting) and meat (protein) in the evening is far beyond my comprehension. No, they think there couldn’t have possibly been anything “good for you” until the AMA and the guvmint said so.
The fruits caveman ate for a million years were tiny, not these unnaturally softball-sized sweet apples and oranges. Fruitarians would have to spend their whole day gathering little sour fruits with worms if they really wanted to eat naturally. A modern apple is nutritionally about the same as eating a mini-Snickers candy bar with a glass of water.
Does it lose the "estrogen effect" because the amount of isoflavones are reduced? I'm not sure I understand your concern. It is true that in fermented soy foods the hydrolysis will cause more of the isoflavones to occur as aglycones. The isoflavones of unprocessed soy beans will occur as glycosides however, thanks to in vivo hydrolysis there will be hardly any difference at all between the availability of isoflavone aglycones and isoflavone glycosides.
We eat most of our soy as isolated soy protein which is almost entirely protein. What is your concern here?
We can eat extremely copious amounts of processed soy which acts like estrogen in the body.
Most people aren't aware that endocrine disruptors exist in many places and that many foods we eat possess some of the same characteristics. Chocolate, garlic, celery, coffee, grapefruit, tea, and cola have been shown to have antispermatogenic activity. The horror!
There are more than 300 plants, in 16 common families, containing estrogens that may bind with receptors of humans or wildlife. Naturally occurring estrogens are plentiful in cereals, legumes, fruits, and vegetables. Endocrine disruptors are all around us and we eat some of them every day in natural foods. I don't see anyone creating fear over fruits, cereals and vegetables. You?
The remainder of your post is nothing more than fear mongering based on junk science. To think we're turning boys into girls because they consume soy is absurd.
This study is junk and there's been a lot of criticism of it. This "study" was very small in scope and was based on recollected intake of soyfoods and not on specific diets containing soyfoods. One critic, Dr. Tammy Hedland, a researcher on male fertility issues, including soy, from the Health Sciences Center, Department of Pathology at the University of Colorado, said "This study is confounded by many issues, thus I feel the results should be viewed with a great deal of caution". She noted that the research did not find a negative relationship between soy and sperm mobility or sperm quality, which are both key factors to fertility. The study also did not determine directly what other foods, medications, supplements, existing medical conditions, sexual activities or environmental factors may have directly affected the drop in sperm count.
This researcher, Chavarro, even admitted his research is a joke. He said that many East Asian men consume much more soya than the participants in his trial and do not develop fertility problems. He speculates that his study found a link between soya and low sperm count because many of the participants were overweight or obese. Men with high levels of body fat produce more estrogen than their slim counterparts."
Wow. He spent all that time and money to determine something we've known for some time now. Nothing like grabbing for that grant money, eh?
There has been extensive human and primate research where controlled amounts of isoflavones from soy have been fed to subjects without any effect on the quantity, quality or motility of their sperm. This research has also found that soy has a preventative effect against prostate cancer.
There are also plenty of clinical studies showing that soy foods and isoflavones do not impact serum levels of testosterone or estrogen. Several of these studies have found no effects on testosterone levels even when they fed their subjects isoflavones at 20 - 30 times the normal level of consumption.
The only thing to fear is people who don't know what they're talking about or who are more interested in funding research than they are with finding the truth.
Actually, that’s not quite true. Almost all humans produce lactase (the enzyme required to digest milk) at birth in order to digest their mother’s milk, which is about 9% lactose. In most populations, as the child is weaned, their need to produce lactase goes away as they consume less and less milk, so they ‘become’ lactose intolerant as they become adults. However, with the domestication of sheep, goats, and other dairy animals around the mediterranean, the people who raised them consumed milk their entire lives, so their lactase production never stopped. Eventually, a genetic quirk that caused lactase production through adulthood somehow came about and quickly became dominant in the populations that consumed lots of dairy products, which is why Europeans have such a low rate of lactose intolerance, and most of them who are lactose intolerant suddenly became so at some point in their life. The lactose intolerance in Asians didn’t happen because of the traditional diet, they just never really became lactose tolerant in the first place because of their traditional diet.
So, you’ve got it partially right. In any case, I’m lactose intolerant so I LOVE soy products.
Thanks for the info.
Could really go for a big plate of Gen Tso’s bean curd about now...
The versions of those foods that we eat are not naturally occurring. We've only been eating farm food for about 500 human generations, and living past 30 has become normal only during the last 10 generations. All the subtle effects of modern foods are not known. Just because a patch of weeds produced soybean-looking beans somewhere on Earth for the last million years doesn't mean modern soybeans are natural or safe. They should be studied with a scientist's skepticism and suspicion.
Well of course they are. How else did they get here? Just because something has been modified genetically doesn't mean the entire chemical composition of the food is new and different. Just about every food you eat today has been genetically altered in some way yet we live longer, healthier lives today than at any time in the past. If you had to survive on foods that only occurred naturally, or existed more than 500 human generations ago, you'd get tired of eating the same thing every day if you didn't starve first.
All the subtle effects of modern foods are not known.
And probably never will be as long as the alarmists continue to instill fear in the public based on junk science.
Just because a patch of weeds produced soybean-looking beans somewhere on Earth for the last million years doesn't mean modern soybeans are natural or safe.
Until you find some legitimate research that proves otherwise, you'll have to accept the fact that they are safe.
They should be studied with a scientist's skepticism and suspicion.
And they have been for a long time now. You can either accept the conclusions of the legitimate research or buy in to the nonsense of the toxic terrorists. The choice is yours.
Exactly, less libtards, what’s the downside?
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