Eating soya could slash men's sperm count

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ThaG

Sicc OG
Jun 30, 2005
9,597
1,687
113
#1
interesting...

http://environment.newscientist.com/article.ns?id=dn12792&feedId=online-news_rss20

Men who eat just half a serving of soya a day have drastically fewer sperm than those who do not consume such foods, according to a small, preliminary study.

The study's researchers say larger trials are needed to determine whether men hoping to conceive a child should try to avoid soya foods, such as tofu, tempeh and soya milk. However, soya industry representatives caution that the new findings contradict earlier studies that have shown no impact on sperm count from soya-based products.

Soya foods contain high amounts of isoflavones, compounds that mimic the effects of oestrogen in the body. For this reason, women sometimes increase their intake of soya foods to treat hot flushes caused by declining oestrogen levels in menopause.

Oestrogen-like compounds can also have a dramatic impact on the male body. And previous rodent studies have suggested that high intake of soya products can reduce male fertility. This has led scientists to wonder how isoflavones might influence men's reproductive function, which is highly sensitive to hormones.
Soya survey

Jorge Chavarro at the Harvard School of Public Health in Boston, Massachusetts, US, and his colleagues identified 100 couples seeking treatment for infertility. Researchers asked the men to provide semen samples and complete a questionnaire about their intake of 15 soya-based foods such as miso soup, "power bars", and tofu over the preceding three months.

An analysis of the data, which controlled for factors such as age and weight, revealed that those men who consumed half a serving of soya-based food each day - about the equivalent of half a soya burger - had 65 million sperm per millilitre on average.

That is about 40% less than the typical sperm count of men who do not eat such foods - normally between 80 million to 120 million sperm per millilitre. Men with counts lower than 20 million sperm per millilitre are generally considered infertile.

Chavarro presented the new findings at the annual meeting of the American Society for Reproductive Medicine in Washington, DC on Monday.
Harvesting conditions

Researchers speculate that isoflavones from soya products might lower sperm count by interfering with other hormonal signals that drive sperm production in the testes. They say that further studies are needed to assess whether the drop in sperm count seen in men consuming soya could translate into reduced fertility.

But some experts are sceptical about the new findings. Earlier studies involving men and primates with carefully controlled isoflavone intake have not observed an effect on sperm, according to Stephen Barnes, a toxicologist at the University of Alabama at Birmingham, US, who has studied the influence of soya foods.

The result from Chavarro's study stands in stark contrast to previous findings. "It doesn't fit in with the rest of what has been done experimentally," says Barnes. "But that's not to say it's wrong," he adds.

Industry representatives also note that because isoflavone content in a given food can vary widely based on harvesting conditions, it is difficult to draw conclusions about the impact of soya from retrospective surveys of food consumption.
Obesity link

"Unless researchers are measuring the actual isoflavone content it would be difficult to know the impact of soya foods on sperm count," says Nancy Chapman, executive director of the Soyfoods Association of North America based in Washington, DC. "When you do an observational trial like this there could have been other behaviours causing this decline in sperm count."

Chavrro admits 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 oestrogen than their slim counterparts. "They already have a lot of background estrogen," says Chavarro.

He believes that the oestrogen-mimicking isoflavones in soya might push the hormonal levels in overweight and obese men even higher, to the point at which sperm begin to suffer.
 
Jun 13, 2002
13,154
525
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siccness.net
#5
Yeah man, I been up on soy...

http://www.bodybuilding.com/fun/author25.htm


By:
Author Rea


Though most know me for my books, columns and articles on AAS (Anabolic Androgenic Steroids), over the past several years I have written on supplements extensively as well. After all, chemistry is chemistry whether it is food, steroids, training or water. One either understands this or fails to realize the potential of knowledge that will advance training results.
As of late, it seems that I have been getting more and more questions about soy protein and my reasons for suggesting that athletes, and especially male athletes, avoid it like a bad blind date. As such, I would like to offer some broader insights upon this evil substance. In truth, with the exception of post-menopausal women, there just is no valid reason to suggest that the evils of soy food or protein use out weight the benefits.

What Is Soy?
Soy comes from soybeans. They grow in those fuzzy green pods we sometimes see in the grocery store masquerading as a vegetable. They come in other colors but for the most part are sort of a yellow/tan color with a single black eye.
At one time the Asian soybean plants were grown to be used as a replacement for manure thus used to cover crops and intended to be plowed into the soil for nutrient enrichment. Yup, it was fertilizer. Naturally, like anything else in life, there is always someone who could not leave $#!^ alone.
Sometime during the Chiang Dynasty, the Chinese decided to ferment the fuzzy beans and human consumption began from such as soy sauce and miso. Naturally tofu followed soon thereafter.
Later in the West, the soybean was used predominantly for soy oil. Big deal? Soy oil is used to make shortening, margarine and many vegetable oils.
After the soy oil extraction process has been completed there is a great deal of soy protein left over. For many years this was used solely to feed animals, poultry and even fish. The only problem is that there is a limit as to how much soy protein can be used to replace other feeds before the animals develop major health problems including reproductive.
Currently soy is used as a meat substitute and in many food products as well. Oh, and many pet foods are dependant upon soy as a protein source. Oddly enough many who swear they never eat soy products find they consume them daily in processed foods...once they take a look.

Soy Is A Health Food?
Around the mid-70's the soy industry employed top marketing firms to convince the poor and middle class people of most countries that soy was not just $#!^ but really a health food. The idea was to dispel the fact that it was just a cheap calorie source for animals as well.
The United Soybean Board (USB) has spent millions of dollars to lobby aggressively in Washington (The Capital of The United States) and medical research. In fact they spent over a million dollars on establishing the FDA's (Food and Drug Administration) questionable stand that soy lowers cholesterol.
Additionally the USB has romanced writers, editors, dietitians, chefs and about every processed food manufacturer for favorable words in the behalf of soy. Needless to say, the strategy has been nothing less than genius. Soy can now be found in almost 65% of the food goods sold in grocery stores.

Why Does Soy Suck?

Soy products contain:

  • [*]Phytoestrogens: (isoflavones) genistein and daidzein, which mimic and sometimes block the hormone estrogen
    [*]Phytates: which block the body's uptake of minerals
    [*]Enzyme Inhibitors: which hinder protein digestion
    [*]Haemaggluttin: which causes red blood cells to clump together and inhibits oxygen take-up and growth.

Pesticides
Further more, most soybeans are grown on farms that use toxic pesticides and herbicides, and many are from genetically engineered plants. When you consider that two-thirds of all manufactured food products contain some form of soy, it becomes clear just how many Americans are consuming products, whose long-term effects are completely unknown.

Emasculation And Fat Deposits?

Perhaps the most disturbing of soy's ill effects on health has to do with its phytoestrogens that can mimic the effects of the female hormone estrogen. These phytoestrogens have been found to have adverse effects on various human tissues, and drinking even two glasses of soy milk daily for one month has enough of the chemical to alter a woman's menstrual cycle.
The FDA regulates estrogen-containing products, however no warnings exist on soy. Two senior toxicologists with the FDA. Daniel Sheehan and Daniel Doerge, have even come out saying "The public will be put at potential risk from soy isoflavones in soy protein isolate without adequate warning and information."
Soy is particularly problematic for infants, and soy infant formulas should be avoided. Why? Based on figures from the Swiss Federal Health Service, it has been estimated that infants who are fed soy formula exclusively receive five birth control pills worth of estrogen every day.
The studies that supposedly prove that infants on soy formula develop normally consider only height, weight and other measurements of growth as measured in infancy and early childhood. Many of the negative effects don't become obvious until puberty. Think about that next time you walk through the locker room at the gym.
Pediatricians are reporting more and more cases of emasculated boys reaching puberty with breasts and tiny penises. Undescended testicles are also far more common than they were in the past.
Remember too that soy estrogens damage far more than the reproductive system. The thyroid is usually hurt first, leading to loss of energy, weight gain, depression, lethargy, and a host of other symptoms.
In mature adults soy lowers testosterone and sperm production in males and increases fat deposits in most females. Almost every soy product available (soy protein products too) contains phytoestrogens. (Supplemental bitch status. Yikes!)

Kidney Stones?

Oxalate is a nasty substance found in some foods. The amount of oxalate in the commercial products easily eclipsed the American Dietetic Association's 10 milligram-per-serving recommendation for patients with kidney stones, with some foods reaching up to 50 times higher than the suggested limit. Under these guidelines, no soybean or soy-[based] food tested could be recommended for consumption by patients with a personal history of kidney stones.
During food stuffs testing, researchers found the highest oxalate levels in textured soy protein, which contains up to 638 milligrams of oxalate per 85-gram serving. Soy cheese had the lowest oxalate content, at 16 milligrams per serving.
Spinach has approximately 543 milligrams per one-cup (2 oz. fresh) serving. Oxalate cannot be metabolized by the body and is excreted only through urine. The compound has no nutritional value, but binds to calcium to form a mass (kidney stones) that can block the urinary system.
No one knows precisely why kidney stones occur in particular individuals. However we do know that high levels of oxalate in the urine increase the risk and those with a family history of the ailment are more likely to suffer from the condition.
More than ONE MILLION people were diagnosed with kidney stones in the United States in 2002. Stones can range in size from the diameter of a grain of rice to the width of a golf ball. An estimated 10 percent of the U.S. population, mostly men, will develop a kidney stone at some point in their lives.

In Closing

It appears that with today's new push toward low carbohydrate foods that an even more powerful thrust from the soy industry has come with it. From low-carb pastas to no-carb sauces everyone is advertising better health without disclosing the hidden evils of cheap protein once used to replace shit.
Naturally we do not need to avoid soy completely unless you are allergic to soy that is. A little soy sauce on occasion is not going to make anyone's testicles fall off. However, as a protein source or even as a daily food stable in anyway is anti-health for all athletes whom are not menopausal.

References

  1. [*]New Zealand Medical Journal (Volume 113, Feb 11, 2000).
    [*]Journal of Agricultural and Food Chemistry September 2001.
    [*]Int J Food Sci Nutr. 2004 Apr;55(3):201-5.
    [*]Toxicol Lett. 2004 Jun 15;151(1):151-62.
    [*]Am J Vet Res. 2004 May;65(5):592-6.