solid info on soy

[Guest guest]

http://www.drmcdougall.com/misc/2005nl/april/050400pusoy.htm

 

Soy - Food, Wonder Drug, or Poison?

by John McDougall

 

Soy-food consuming populations of people, like the Chinese and

Japanese, have a much lower incidence of heart disease, osteoporosis,

and cancer of the breast and prostate. From this observation,

many researchers have come to the conclusion that ingredients in the

soybean have anticancer, antihypertensive, and anti-cholesterol

benefits, and also act as a natural alternative to hormone replacement

therapy. Soy foods have become synonymous with health food and

vegetarianism. Their popularity is tied to the belief that soy has

"wonder-drug" benefits - so powerful that many people suppose they

can safely eat their bacon and eggs for breakfast as long as they

finish off their morning meal with a cup of soy

yogurt.

 

 

 

However, there is a dark side to the soy story that warns that these

foods may increase your risk for cancer, impair your thyroid, immune,

and brain function, and cause you bone loss and reproductive

problems. Fortunately, these worries are relevant mostly for

people lured into consuming "fake foods" synthesized from man-made

components of soy and other foods, and high potency soy supplements -

not for those who consume traditional soy foods as a small portion of

their diet.

 

Soy's Effects Are Usually Inconsequential

 

In Asian countries, soy is consumed as boiled soybeans (edamame), tofu

(soybean curd), natto (fermented soybeans), miso (fermented soybean

paste), okara (a by-product of tofu), soybean sprouts, soymilk, yuba

(by-product of soy milk), kinako (soy flour), and soy sauce.

These foods are made from simple processes like grinding,

precipitation, and fermentation - thus, most of soy's ingredients

remain little altered. Less than 5% of daily calories in the typical

diet of Japanese or Chinese people comes from soybeans.1 This

amounts to about 2 ounces (55 to 64 grams) derived from soy foods

daily, which means only 7 to 8 grams of protein and 15 to 45

milligrams of the estrogen-like phytochemical known as isoflavone.

How could this tiny amount of soy food make a measurable difference -

positive or negative - to the health of Asians?

 

The primary reason these people are so hardy is that the Asian diet is

based on a starch - rice - with generous amounts of vegetables and

fruits. Starches are ideal foods for human nutrition and have

many desirable nutritional qualities - they are low in fat, moderate

in protein, high in carbohydrates, and contain no cholesterol.

The Asian diet also contains few animal products. Any

unique pharmacologic benefits from eating soy are unnoticeable

compared to the impact of these people's overall diet. (For a

discussion of the benefits of starches, see my April 2004 newsletter

article: People - Not Their Words - Tell "The Carbohydrate

Story.")

 

________________SIDEBAR____

We recommend that you use traditional soy foods, like soy milk and

tofu, only as a small part of your diet, at most 5% of your daily

calories. "Synthetic soy foods," like meats, cheeses, and

soy bars, should rarely, if ever, be consumed.

 

Examples of sensible uses might be:

 

Soy milk to moisten cereal, not glassfuls as a beverage

 

Tofu pieces in a "stir-fry" rice dish, not as a soy burger

entrée

 

An occasional tofu-based dessert, not daily soy "candy" bars

_________

 

Soy - Detrimental or Beneficial

 

The truth behind soy is clouded by emotional reactions from the

anti-soy movement of hard-core meat-eaters and soy-loving vegetarians

- and as usual, money from big businesses, the soy manufacturers.

Most of the rhetoric on both sides of the argument is of no real

importance - the real issue is whether you are consuming small

amounts traditional soy foods or making yourself a diet of synthetic

foods.

 

The Seven Main Arguments:

 

Argument 1: Anti-nutrients

 

Detrimental: Soy contains "anti-nutrients," which interfere

with the digestion of proteins (trypsin inhibitors) and the absorption

of minerals (phytic acid).

 

Beneficial: These "anti-nutrient" substances are deactivated

by cooking and fermentation. Cooking before consumption is not

unique to soybeans - no other beans, peas, or lentils are eaten

"raw." Although adverse effects on experimental animals have been

demonstrated, there is no direct evidence as to the physiological

effects of the trypsin inhibitors on humans.2 Interestingly,

Phytic acid has anticancer effects in animal models for both colon and

breast cancer.3

 

Argument 2: Cancer

 

Detrimental: Soy has estrogen-like activity that may promote the

growth of estrogen-sensitive cancers (breast and prostate), especially

for those people who already have cancer.4-5

 

Beneficial: Breast and prostate cancer rates are four to six times

lower in Japan and China than Western countries. In laboratory

studies, isoflavone from soy can inhibit the growth of breast cancer

and prostate cancer tissues.6

 

Argument 3: Heart Disease

 

Detrimental: Benefits on heart disease are largely unproven and

are really due to the low-fat, low-cholesterol qualities of the Asian

diet.

 

Beneficial: People living in countries with more soy in their diet,

for example Japan, have a much lower risk of heart attacks.

Experimental research consistently shows soy foods cause a decrease in

total and "bad" LDL cholesterol, and an increase in "good"

HDL-cholesterol.7-8 Products containing at least 6.25

grams of soy protein per serving are now allowed to carry a

FDA-approved claim on their label; stating a low-fat, low-cholesterol

diet containing at least 25 grams (about one ounce) of soy protein a

day may reduce one's risk of heart disease.

 

Argument 4: Sex Hormones

 

Detrimental: Twelve ounces of soy milk drunk three times a day for one

month will decrease a woman's estradiol and progesterone levels, and

her menstrual cycle length will be increased by about four days.9

These effects may cause infertility and contribute to bone loss.

 

Beneficial: Chinese and Japanese are among the most prolific

baby-makers in the world. Phytoestrogens have both a weak

estrogen-stimulating (estrogenic) and paradoxically, an

estrogen-inhibiting (anti-estrogenic) activity. The

estrogen-like activities may strengthen bones and prevent menopausal

symptoms like hot flashes. Hot flashes are reported by 70% to 80% of

US menopausal women compared to 10 to 14% of women in Japan and

Singapore.10 The anti-estrogen activity reduces the risk of breast and

uterine cancer.

 

Argument 5: Thyroid

 

Detrimental: Goiter and hypothyroidism have been reported in infants

receiving soy formula. Autoimmune diseases of the thyroid and

thyroid cancer may also be caused by exposure to soy.11-12

 

Beneficial: The addition of adequate iodine to the diet reverses

any goiter-causing effects of soy. Population studies suggest

soy protects against thyroid cancer.13

 

Argument 6: Immune System

 

Detrimental: In experimental studies, soy isoflavone

suppresses the immune system, and reduces the size of the thymus

gland. There are reports of a decrease in antibodies, white blood

cells, and other indications of immune system malfunction with soy

consumption.14-19

 

Beneficial: Soy isoflavone enhances the immune response and

provides a possible explanation for lower incidence of certain cancers

in soy-eating parts of the world.20,21 The pain of arthritis has

been helped by soy through modulating the immune system.22

 

Argument 7: Brain Health

 

Detrimental: A recent study of middle-aged Japanese-Americans living

in Hawaii found adults consuming tofu had reduced brain function,

accelerated brain aging and some structural changes in their brains

that might be related to Alzheimer's disease.23

 

Beneficial: Alzheimer's disease and other forms of dementia

are less common in Asian compared to Western populations.24

Recent studies have actually shown improvement in brain functions with

the use of soy supplements.25,26

 

In summary, population studies fail to support real-life soy-caused

diseases, experimental data is inconsistent, and the larger components

of the diet (starches, vegetables, and fruits) are most likely the

reason for the superior health of soy consuming peoples.

 

The Whole Is Healthier Than the Parts

 

Over the past two decades there has been an explosion on the

supermarket shelves of soy products that resemble our favorite meat

and dairy products. I often refer to these as "fake foods."

Manufacturing processes remove the dietary fibers, carbohydrates,

fats, vitamins, minerals, and hundreds of other helpful plant

chemicals - leaving behind almost pure soy protein.

 

These protein concentrates are mixed with extracts of wheat protein,

vegetable oils, and sometimes, starch, sugar, salt, artificial

sweeteners, and dairy and egg proteins - then the magic of modern

technology turns these mixtures into products that look and taste like

real cheese, hot dogs, sausages, burgers, luncheon meats, chicken, and

turkey. Soy protein is used to replace dairy protein in candy bars,

yogurt, ice cream, breads, pastries and cookies. You can

identify the synthesized concentrated proteins on the ingredient list

of your foods by these words: defatted soy flour, organic textured soy

flour, textured vegetable protein, isolated soy protein, soy protein

concentrates, and soy concentrates. These new "foods" in no

way resemble nature's creations and the effects on your health make

that clear.

 

Calcium Loss and Cancer Growth from Protein Concentrates

 

Concentrated dairy (cow-milk) protein, when consumed by people, causes

large and important loses of calcium contributing to osteoporosis and

kidney stones. You would hope that replacement with soy protein

concentrates would eliminate this health hazard. Unfortunately,

recent research on people has demonstrated that the addition of 40

grams of concentrated soy protein to a diet, already low in protein

(40 to 50 grams daily) and high in calcium (1100 mg daily), causes

significant net losses of calcium from the body.27 Other

research shows isolated soy protein is just as damaging as meat

protein to the bones.28

 

Another recent study showed how 40 grams of soy or cow-milk protein

concentrate added to the diet significantly increases levels of a

powerful cancer-promoting growth hormone, called Insulin-like Growth

Factor 1 - IGF-1.29 However, soy protein was almost twice as

powerful as the milk protein concentrate - doubling the levels of

IGF-1 with 40 grams of soy protein isolate. This growth promoter

has been strongly linked to the development of cancer of the breast,

prostate, lung, and colon.30 Excess IGF-1 stimulates cell

proliferation and inhibits cell death - two activities you

definitely don't want when cancer cells are involved. 30

 

What does 40 grams of isolated soy protein mean to you? In real

life, a person seeking excellent health by following a low-protein

version of the McDougall diet with 1100 mg of calcium (which would

have to be added with a calcium supplement) becomes at risk for

osteoporosis, kidney stones, and cancer with the daily addition of a

soy "candy bar" and a soy shake. One soy "chicken" patty

for lunch and 2 soy burgers for dinner will also add that 40 grams of

isolated protein daily - and so will just four soy breakfast

patties. Now soy has real meaning in your life.

 

The effects of adding soy protein concentrates on people already

consuming the bone-losing, high-animal-protein Western diet (100 to

160 grams of protein daily), or worse yet, the Atkins diet (up to 300

grams daily) have yet to be determined.31 Because of the very low

incidence of osteoporosis, and breast and prostate cancer, among

people who consume traditional soybean foods, there is every reason to

believe that only the synthetic soy foods need to be of concern.

(Studies have yet to be done to specifically test the effects of

traditional foods in laboratory settings - in the meantime, we will

keep these as a small part of our diet.)

 

Examples of Common Foods with Protein Isolates

 

Eating "fake foods" adds 40 grams of protein concentrate

effortlessly to your diet: [see web link for table; examples include

Cliff® Builder's Bar, Cliff® Bar (Oatmeal, Raisin Walnut),

Revival Soy Bars®, Morningstar Farms® Sausage Patties, Boca©

Breakfast Links, Gardenburger® Chik'n Grill, Boca Burger®

Original, Boca® Ground Burger, Boca® Chicken Patties, Smart

Dogs®, Boca® Chili, Veggie Shreds® (Cheese), Boca® Pizza, Tofu

with Added Isolates (Lite Tofu®), Benesoy® High Protein Soy

Flour.

 

Many of these foods also contain an isolated wheat protein (gluten)

which has similar effects on calcium loss.32

 

 

Pharmaceutical-grade Soy Hormones

 

Phytochemicals found in plants are important ingredients for radiant

health, but must be consumed in their natural packages - like the

traditional soy foods - to reap the most benefits with the least

risks. After isolation from their natural environment - the

soybean - these chemicals unquestionably become

pharmaceuticals.

 

Manufacturing processes concentrate the pharmacologic ingredients of

soy into powerful drugs sold to women to treat menopausal symptoms and

osteoporosis. Unfortunately, drugs have side effects. A

concentrated preparations of isoflavone, sold as Novasoy®, and

mixtures of the active chemicals (isoflavone and/or genistin), have

been shown to be strong promoters of breast cancer growth in

animals.33 Long-term treatment (up to 5 years) with soy

isoflavone preparations was associated with an increased occurrence of

endometrial hyperplasia in women - a precancerous condition of the

female uterus.34

 

Soy Infant Formula

 

Soy baby formula is synthesized from pure sugar (corn syrup), oil

(safflower), and protein (soy protein isolate) - this is the epitome

of "fake food" - especially when considering the potential

consequences. Approximately 1.4 million (36%) infants per year

in the United States receive soy formula. Because 100% of the

dietary protein and isoflavone that the baby gets is from soy, the

chemical compounds reach levels many times higher than the levels

found in adults who consume soy foods - and even exceed

concentrations shown to be toxic in laboratory experiments. For

example, daily exposure to estrogen-like compounds from soy formula

results in levels 6 to 11 times higher in infants than the level that

will cause changes in the menstrual cycle of women.35-36

 

The reason so little is known about the harmful effects of feeding soy

formula to babies is that these effects in real life situations have

not been adequately studied. However, some indication of the

sensitivity of a baby to soy's estrogen-like effects might be

learned from a recent study finding birth defects of the genitalia of

male infants (hypospadia) born to mothers who consumed large amounts

of soy products.37

 

Reserve Traditional Soy foods for Special

 

Despite concerns, there is no definite evidence that traditional soy

foods are harmful at levels customarily consumed. Consider

the hundreds of millions of people living in Japan, consuming soy

products throughout their life - and they enjoy the longest life

expectancy in the world (Japanese women are expected to live 84.93

years, compared to US women to 79.5 years; and Japanese men to 78.07

years, compared to 74.1 years for US men).

 

However, soybeans and their by-products should be thought of as rich

foods - naturally high in fat and protein. In their

traditional forms consider them as delicacies - and you should

consume them as you might other plant food delicacies - nuts, seeds,

avocados, and olives - in small amounts on special occasions.

 

Soybeans Are Nutritionally between a Bean and a Nut

 

These soy items are rich plant foods (look at the fat and protein

contents)

[see web link for table showing nutritional comparison of

beans and traditional soy foods]

 

References:

 

1) Nagata C, Takatsuka N, Kurisu Y, Shimizu H. Decreased serum

total cholesterol concentration is associated with high intake of soy

products in Japanese men and women. J Nutr. 1998

Feb;128(2):209-13.

 

2) http://www.fao.org/docrep/t0532e/t0532e01.htm

 

3) Vucenik I, Shamsuddin AM. Cancer inhibition by

inositol hexaphosphate (IP6) and inositol: from laboratory to clinic.

J Nutr. 2003 Nov;133(11 Suppl 1):3778S-3784S.

 

4) Newbold R. Uterine adenocarcinoma in mice treated

neonatally with genistein. Cancer Res. 2001 Jun 1;61(11):4325-8.

 

5) Cassileth BR, Vickers AJ. Soy: an anticancer agent in

wide use despite some troubling data. Cancer Invest.

2003;21(5):817-8.

 

6) Adlercreutz H. Phyto-oestrogens and cancer. Lancet

Oncol. 2002 Jun;3(6):364-73.

 

7) Jenkins D. Effects of high- and low-isoflavone

soyfoods on blood lipids, oxidized LDL, homocysteine, and blood

pressure in hyperlipidemic men and women. Am J Clin Nutr. 2002

Aug;76(2):365-72.

 

8) Anderson JW, Johnstone BM, Cook-Newell ME Meta-analysis of

the effects of soy protein intake on serum lipids. N Engl J Med. 1995

Aug 3;333(5):276-82.

 

9) Lu L. Effects of soya consumption for one month on steroid

hormones in premenopausal women: implications for breast cancer risk

reduction.

Cancer Epidemiol Biomarkers Prev. 1996 Jan;5(1):63-70.

 

10) Glazier M. A review of the evidence for the use of

phytoestrogens as a replacement for traditional estrogen replacement

therapy. Arch Intern Med. 2001 May 14;161(9):1161-72.

 

11) Divi R. Anti-thyroid isoflavones from soybean:

isolation, characterization, and mechanisms of action. Biochem

Pharmacol. 1997 Nov 15;54(10):1087-96.

 

12) Doerge DR, Sheehan DM. Goitrogenic and estrogenic activity

of soy isoflavones. Environ Health Perspect. 2002 Jun;110 Suppl

3:349-53.

 

13) Horn-Ross PL, Hoggatt KJ, Lee MM. Phytoestrogens and

thyroid cancer risk: the San Francisco Bay Area thyroid cancer study.

Cancer Epidemiol Biomarkers Prev. 2002 Jan;11(1):43-9.

 

14) Yellayi S. The phytoestrogen genistein induces thymic

and immune changes: a human health concern? Proc Natl Acad Sci U

S A. 2002 May 28;99(11):7616-21.

 

15) Zoppi G. Immunocompetence and dietary protein intake

in early infancy. J Pediatr Gastroenterol Nutr. 1982;1(2):175-82.

 

16) Zoppi G. Gammaglobulin level and soy-protein intake in

early infancy. Eur J Pediatr. 1979 Apr 25;131(1):61-9.

 

17) Zoppi G. Diet and antibody response to vaccinations in

healthy infants. Lancet. 1983 Jul 2;2(8340):11-4.

 

18) Fort P. and soy-formula feedings in early infancy and the

prevalence of autoimmune thyroid disease in children. J Am Coll Nutr.

1990 Apr;9(2):164-7.

 

19) Alexandersen P. Ipriflavone in the treatment of

postmenopausal osteoporosis: a randomized controlled trial.

JAMA. 2001 Mar 21;285(11):1482-8.

 

20) Watanabe S, Uesugi S, Kikuchi Y. soflavones for prevention

of cancer, cardiovascular diseases, gynecological problems and

possible immune potentiation. Biomed Pharmacother. 2002

Aug;56(6):302-12.

 

21) Jenkins DJ, Kendall CW, Connelly PW, Jackson CJ, Parker T,

Faulkner D, Vidgen E. Effects of high- and low-isoflavone

(phytoestrogen) soy foods on inflammatory biomarkers and

proinflammatory cytokines in middle-aged men and women. Metabolism.

2002 Jul;51(7):919-24.

 

22) Arjmandi BH, Khalil DA, Lucas EA, Smith BJ, Sinichi N,

Hodges SB, Juma S, Munson ME, Payton ME, Tivis RD, Svanborg A.

Soy protein may alleviate osteoarthritis symptoms.

Phytomedicine. 2004 Nov;11(7-8):567-75.

 

23) White LR, Petrovitch H, Ross GW, Masaki K, Hardman J, Nelson J,

Davis D, Markesbery W. Brain aging and midlife tofu

consumption. J Am Coll Nutr. 2000 Apr;19(2):242-55.

 

24) Jorm AF, Jolley D. The incidence of dementia: a

meta-analysis. Neurology. 1998 Sep;51(3):728-33.

 

25) Kritz-Silverstein D, Von Muhlen D, Barrett-Connor E, Bressel

MA. Isoflavones and cognitive function in older women: the

SOy and Postmenopausal Health In Aging (SOPHIA) Study.

Menopause. 2003 May-Jun;10(3):196-202.

 

26) File SE, Hartley DE, Elsabagh S, Duffy R, Wiseman H.

Cognitive improvement after 6 weeks of soy supplements in

postmenopausal women is limited to frontal lobe function. Menopause.

2005;12(2):193-201.

 

27) Spence LA, Lipscomb ER, Cadogan J, Martin B, Wastney ME,

Peacock M, Weaver CM. The effect of soy protein and soy

isoflavones on calcium metabolism in postmenopausal women: a

randomized crossover study. Am J Clin Nutr. 2005

Apr;81(4):916-22.

 

28) Roughead ZK, Hunt JR, Johnson LK, Badger TM, Lykken GI.

Controlled substitution of soy protein for meat protein: effects on

calcium retention, bone, and cardiovascular health indices in

postmenopausal women. J Clin Endocrinol Metab. 2005

Jan;90(1):181-9. Epub 2004 Oct 13.

 

29) Arjmandi BH, Khalil DA, Smith BJ, Lucas EA, Juma S, Payton

ME, Wild RA. Soy protein has a greater effect on bone in

postmenopausal women not on hormone replacement therapy, as evidenced

by reducing bone resorption and urinary calcium excretion. J

Clin Endocrinol Metab. 2003 Mar;88(3):1048-54.

 

30) Yu H. Role of the insulin-like growth factor family in

cancer development and progression. J Natl Cancer Inst. 2000 Sep

20;92(18):1472-89.

 

31) Reddy ST. Effect of low-carbohydrate high-protein diets on

acid-base balance, stone-forming propensity, and calcium metabolism.

Am J Kidney Dis. 2002 Aug;40(2):265-74.

 

32) Jenkins DJ, Kendall CW, Vidgen E, Augustin LS, Parker T,

Faulkner D, Vieth R, Vandenbroucke AC, Josse RG. Effect of high

vegetable protein diets on urinary calcium loss in middle-aged men and

women. Eur J Clin Nutr. 2003 Feb;57(2):376-82.

 

33) Allred CD, Allred KF, Ju YH, Goeppinger TS, Doerge DR,

Helferich WG. Soy processing influences growth of

estrogen-dependent breast cancer tumors. Carcinogenesis. 2004

Sep;25(9):1649-57.

 

34) Unfer V, Casini ML, Costabile L, Mignosa M, Gerli S, Di

Renzo GC. Endometrial effects of long-term treatment with

phytoestrogens: a randomized, double-blind, placebo-controlled study.

Fertil Steril. 2004 Jul;82(1):145-8,

 

35) Setchell K. Exposure of infants to

phyto-oestrogens from soy-based infant formula. Lancet. 1997 Jul

5;350(9070):23-7.

 

36) Chen A, Rogan WJ. Isoflavones in soy infant formula: a

review of evidence for endocrine and other activity in infants.

Annu Rev Nutr. 2004;24:33-54.

 

37) North K. A maternal vegetarian diet in pregnancy is

associated with hypospadias. The ALSPAC Study Team. Avon Longitudinal

Study of Pregnancy and Childhood. BJU Int. 2000

Jan;85(1):107-13.

[Guest guest]

Yarrow?

 

I saw " peninsulapermaculture " somewhere in your identification on

this list. I am interested in permaculture and would like to know if

you have a website or perhaps we could email offlist?

 

thanks,

Marian

 

mb

www.iaomb.com

 

 

, yarrow wrote:

>

> http://www.drmcdougall.com/misc/2005nl/april/050400pusoy.htm

>

> Soy - Food, Wonder Drug, or Poison?

> by John McDougall

>