soya foods.....

kerrysgold

I am thinking of becoming semi-vegan, if that's possible (i.e. no dairy but still eat eggs and honey) but I've heard/read that eating/drinking too much soya product's is unnatural/can't be digested properly and also might cause cancer? Does this also apply to the ''fake meats''? do they contain natural products or does a lot of chemicals go into them? I currently only really eat Quorn sausages and occasionally some ''chicken'' chunks because I eat a lot of lentil-based meals and also a good bit of houmous and also eggs so I figure that provides a good bit of protein. I occasionally have vegan products, like soya/rice milk (the rice milk tastes a bit odd though!) and those Alpro desserts are yummy too lol, but SO expensive so I don't bother buying them too often.

Also, do any other veggies take a supplement like Centrum in case you're lacking in anything? Am considering buying some but not sure if it's any good or just more chemicals! It seems to hard to avoid food that isn't full of chemicals! :eek:

Tar.Aldarion

I wouldn't worry too much, as long as you don't eat insane amounts of these things, as with any food. Everything causes cancer it is said...
If anything the fake meats should be a better choice than the real ones.
I don't use any supplements but there is no harm if you think you need them.

kerrysgold

yeah that's true, even olive oil, it's a good thing I hate the stuff lol.
I'll have to read the packet the next time I get some, I don't have anything in the freezer at the moment lol, shop didn't have any quorn sausages
apparently even cow's have chemicals put in them now, I suppose sheep do too!

Mentalmiss

Please exercise caution and do not over indulge in soy.

www.soyonlineservice.co.nz/03soymyths.htm
www.thefactsaboutfitness.com/news/soya.htm
www.abc.net.au/rn/talks/8.30/helthrpt/stories/s1150263.htm
www.westonaprice.org/soy/soy_badnews.html

sweet-rasmus

Rather than semi-vegan you would be called an ovo-vegetarian. But I understand that very few people will know what you mean by it.

Macha

Here is a very up-to-date, balanced, reasonably scientific article on the subject. These guys take their nutrition very seriously so I consider their advice to be very good:

http://www.precisionnutrition.com/members/showthread.php?t=10896

If you want the 2nd part, let me know & I'll post it here

T

Tar.Aldarion

I'd like part 2.

Peanut

Good to see that, I was starting to worry that my Alpro chocolate addiction was going to have bad consequences...

Parnassia

Mentalmiss wrote: »

Please exercise caution and do not over indulge in soy.

www.soyonlineservice.co.nz/03soymyths.htm
www.thefactsaboutfitness.com/news/soya.htm
www.abc.net.au/rn/talks/8.30/helthrpt/stories/s1150263.htm
www.westonaprice.org/soy/soy_badnews.html

I haven't read any of the other articles, but Weston A Price is a bit of a joke - just have a look at the rest of his site.

Thanks for that link taconnol.

Macha

Tar.Aldarion wrote: »

I'd like part 2.

Ask and ye shall receive. Seek and ye shall find. OK I'll shut up.

Soy - What's The Big Deal?
Part 2
by Ryan Andrews

No More Rats…Humans & Phytoestrogens
Taking it to human studies, data on patients with prostate cancer showed that the intake of 80 mg/day of PEs did not significantly alter testosterone levels.

To go one step further, an intake of PE up to 16 mg/kg of body weight had no significant influence on behavior or physical characteristics.

Taking the dose up again, another study found that 84 straight days of consuming 450 – 900 mg/day of PE lowered DHEA levels and had estrogenic side effects in males with prostate cancer. Not necessarily good. However, skim over the chart above to determine how much soy food that would be - it'd be a freakin' lot!

Revisiting our idea from earlier, the fact that Asian cultures aren't eating tons of soy foods, dietary PE intake has been reported to be about 65 mg/day in some Asian populations, with the Japanese averaging about 45 mg/day. So the conclusion seems pretty simple...small amounts of PEs are probably fine. And small amounts are likely all you'll get with a normal, occasional whole-food soy intake.

Soy and sperm
Have you ever heard of Dr. Jorge Chavarro?

He and his colleagues from Harvard revealed findings from a study that show soy-derived foods and PEs linked to lower sperm concentrations. Not good, right.

However, the research did not find a negative relationship between soy and sperm mobility or sperm quality, which are both key factors to fertility. So maybe it's not that big of a deal after all.

For this study, the researchers surveyed men on their consumption of 15 soy-based foods during the last 3 months and did not directly determine what other foods, medications, supplements, existing medical conditions, sexual activities or environmental factors may have affected the drop in sperm count.

Many of the study participants were overweight or obese, and males with high levels of body fat produce more estrogen than their lean counterparts.

So, in this study, whether it was soy that caused the drop in sperm count or something else is hard to say. Indeed, Asian populations have regularly consumed soy for generations without fertility disorders.

Also, Asian countries have healthy, high functioning children. Dr. Chavarro revealed that East Asian men consume more soy than the participants in his trial and do not develop fertility problems.

Maybe genetics...maybe something else entirely.

Of course, this research aside, there is a body of research in which controlled amounts of PEs were fed to humans or primates and no negative effects on quantity, quality, or sperm motility were noticed.

Other Concerns for Hormonal Manipulation via Diet
With all of the concern and attention being devoted to soy intake and hormonal changes, we always remind ourselves that there are other dietary factors that can have an unfavorable impact on hormone levels.

Chronic alcohol intake is one of the most powerful mediators of sex hormone levels. Ethanol is a testicular toxin.

Chronic male alcoholics develop an assortment of endocrine disorders, including infertility, testicular shrinkage, and feminization, caused in part by elevated production of estrogens and inhibition of testosterone biosynthesis in the testis.

Also, alcohol increases the activity of aromatase, an enzyme that converts testosterone to estrogen in the body.




Also...estrogen.

The major source of animal-derived estrogen in the human diet is milk and dairy foods. 60-80% of the dietary intake of estrogens originates from milk and other dairy foods in the Western world.

In a Western diet, milk is produced predominantly by lactating cattle and gestation is under the control of steroid hormones, including estrogens. Thus, high levels of milk-borne estrogens can be expected.



The milk that we now consume is quite unlike that which was consumed 100 years ago. Authors have hypothesized that milk is responsible, at least in part, for some male reproductive disorders. Other authors have stated that “The Western diet (characterized by milk/dairy products and meat) causes a trend of increasing levels of estrogen.”

Maternal beef consumption (specifically, beef containing hormones) may also alter a man’s testicular development in utero and adverse affect his reproductive capacity.

The point?

Well, it's odd that soy is getting hammered for hormonal implications when, indeed, many of our dietary staples (alcohol, milk, and meat) all might also have an impact on our hormonal levels if we're not conscientious about ensuring adequate exercise and a varied diet.

Rapid-Fire: Soy and Other Health Conditions

Soy and bones
Soy and other plant proteins have a lower net acid excretion, but it still isn’t clear if they have skeletal advantages over animal proteins.

A recent trial in North America looked at the effects of taking soy protein and doing moderate exercise on bone health in post-menopausal women.



43 post-menopausal women completed the trial. They were given either milk protein or soy protein isolate powder (both including calcium and vitamin D), with or without a supervised moderate exercise program (3 x/wk) for 9 months.

Compared with milk powder placebo, women on soy powder had significant reductions in bone turnover, but not in bone mineral density. High bone turnover leads to a greater propensity for fracture.

Two new meta-analyses from China have looked at the effect of PEs on bones.

In the first meta-analysis, data from 10 trials involving 608 menopausal women showed a significant benefit on spine bone mineral density, this was predominantly noticed when PEs were given in higher doses and for longer periods.

In the second meta-analysis, data was combined from 9 trials on 432 subjects and showed that PE significantly increased bone formation and decreased bone resorption.

Soy and body composition
We know that protein is more satiating than carbohydrates and fat, and higher protein diets seem to be important for a healthy body composition, and soy protein seems to be as effective as other proteins in this regard.

An evidence-based review by Drs. Allison and Cope (Univ of Alabama at Birmingham), and Dr. Erdman (Univ of Illinois at Champagne-Urbana), found soy foods equal to other protein sources, such as dairy or meat, in helping to promote fat loss.

The review was published in the November 2007 issue of Obesity Reviews. The review found that individuals lost equivalent amounts of weight (and inches in some cases), using soy protein, dairy milk meal replacements, and beef or pork at equal calorie levels.

Soy and anti-nutrients
Trypsin inhibitors? Phytic acid?

No, these are not characters from the new Shrek movie. These are substances found in soy foods. The good news is that they are deactivated by cooking and fermentation. So consumed cooked and fermented soy foods won’t inhibit protein and mineral absorption.

Also, phytic acid may have anti-cancer properties.

Soy and the heart
The American Heart Association (AHA) gives the “bottom line” about soy on their website:

“Taking soy or isoflavone supplements is unlikely to reduce your risk of heart disease. Eating foods that contain soy protein to replace food high in animal fats may prove beneficial to heart health.”

Now, I don’t place much weight on the opinion of the AHA.

Why?

Well, take a look at the following:




You have to look close, but this side of this box of Nutri-Grain Yogurt Bars, we've got the AHA stamp of approval.

Ever since this was brought to my attention, conclusions made by the AHA mean about as much to me as my mom’s dog taking a crap in the park.

I know, crude. But seriously, ADA. Nutri-Grain yogurt bars? Phhulleeze....How can we believe anything you say now?

Plant protein and kidneys
Soy protein, despite being of very high quality, doesn’t appear to have the same effect on kidney function that occurs in response to animal proteins. So, if your doc, or your mom still gets worried about the high protein meals, mix in some soy for good measure.

Soy Recommendations and Conclusions
Based on all of our readings, discussions and knowledge acquired about soy foods over the past 10 years, it seems that a reasonable amount of unrefined soy intake is fine.

Now, we don’t think soy is anything special in terms of disease prevention. Nor do we think it's extremely harmful in your quest for optimal health, body comp, or performance.

With that said, we do caution against excessive soy intake. When consumption of soy foods is excessive, there might be some negative effects going on.

To this end, it seems best to avoid isolated and highly refined forms of soy on a regular basis. In other words, things like soy isolates, soy concentrates, textured soy protein, etc should be minimized in the diet.

Whole soybeans, soy milks, tofu, tempeh, and miso, on the other hand, are better options.

In terms of total intake, we'd say 1-2 servings of soy per day seems to be a safe and potentially healthy intake, but exceeding three servings per day on a regular basis may not be a good idea.

(A serving is 1 cup of soy milk and 4 ounces of tofu/tempeh/soybeans.)

Now, it’s easy to understand how some individuals can consume excessive amounts of soy. Soy milk on the morning cereal, a soy protein smoothie for a snack, a soy burger at lunch, soy pretzels as a snack, and soy ice cream for dessert. Even a soy novice would recognize that to be soy overload.

So don't make the mistake of eating tons of soy - even if you're on a plant based diet.

Watch out for food pushers
While excessive soy consumption gets a bad rap, we often think about the excessive consumption of any one food and the potential negative effects.
As we presented in this article, what about the high intake of alcohol? Or factory farmed dairy and meat?

Soy is a chief ingredient in the feed of factory farmed animals. Does this indirectly influence the nutrition of meat-eaters? Should they only purchase grass-fed animals?

We hesitate to think that any “mono-food” excess is a good idea on a regular basis.

And, of course, the soy industry does it's part (just like the dairy, egg and beef food pushing industries) to create just that - a mono-food culture. They push soy by overstating the benefits and undermining the concerns.





You might be shocked to know that as a registered dietitian, I receive AT LEAST one mailing per week from a major food industry telling me to push their particular food on my clients.

I'm not making this stuff up, folks.

Now, of course, these messages get the "delete" treatment just as fast as do those annoying penis enlargement emails that also seem to make it through the spam filters.

Just Think
In the end, as JB and I often have discussed, there's a simple rule of thumb that most people somehow forget...repeatedly. And it's this:

You don't often go wrong with whole, unprocessed foods. Where the problems typically occur is with processed food, in all forms.

This rule of thumb is also true with soy. Whole, unprocessed soy, is just a food. It's not a political agenda. It's not a public health crisis. It's not a way of life. It's not a medicine. And it's not a panacea.





It's ONE food - one of a few thousand foods people can include in their diets...or not. It's nothing more.

So, as the title of this article hints at, we want people to re-freakin'-lax when it comes to soy. Moderate doses of whole-food soy proteins really are no big deal.

---

For more great nutrition information like this, check out our Precision Nutrition program at:

http://www.precisionnutrition.com/system.html

---

References:

Soy & muscle
JISSN 2007;4:4.
Nutr J 2004;3:22-27.
J Nutr 2007;137:357-362.
J Sports Med Phys Fitness 2001;41:89-94.

Phytoestrogens
Am J Clin Nutr 1991;54:1093-1100.
Proc Soc Exp Biol Med 1995;208:44-50.
Epidemiol 1993;4:25-31.
J Natl Canc Inst 1996;88:1369-1374.
Toxicol Sci 2001;61:115-127.
Toxicol Sci 1999;51:236-244.
J Chromatogr B Analyt Technol Biomed Life Sci 2002;777:249-260.
Endocrine 2000;13:281-286.
Nutr Cancer 2007;59:163-168.
Nutr Cancer 2004;48:160-170.
Am J Clin Nutr 2002;75:126-136.
Nutr Cancer 1999;33:82-87.
J Epidemiol 2000;10:127-135.
J Nutr. 2002 Mar;132:570S-573S. Review.

Alcohol
Indian J Physiol Pharmacol 2006;50:291-296.
Subst Alcohol Actions Misuse 1983;50:291-296.
Alcohol Alcohol Suppl 1987;1:109-116.
Clin Experi Res 2004;5:780-785.

Other concerns…
Med Hypotheses 2001;57:510-514.
Med Hypotheses 2004;62:133-142.
Hum Reprod 2007;22:1497-1502.

Soy and bones
Menopause 2007;14(3 Pt 1):481-488.
Clin Nutr 2008;27:57-64
Eur J Clin Nutr 2008;62:155-161.
Am J Clin Nutr 2005;81:733-735.
Med Hypotheses 2006;66:1093-1114.
J Nutr 2005;135:1243-1247.


Soy and body composition
Metabolism 2007;56:280-288.

Soy and heart health
J Nutr 1998;128:209-213
Atherosclerosis 2007; Nov 16: Epub.
Am J Clin Nutr 2004;80:1391-1396.

Soy and anti-nutrients
http://www.fao.org/docrep/t0532e/t0532e01.htm
J Nutr2003;133(11 Suppl 1):3778S-3784S.

Soy and Thyroid
Biochem Pharmacol1997;54:1087-1096.
Environ Health Perspect 2002;110 Suppl 3:349-353.
Cancer Epidemiol Biomarkers Prev2002;11:43-49.
Nutr Rev 2003;61:1-33.