Here are some interesting studies which indicate that (unfermented) soya may
not be a sensible dietary replacement for dairy products or lean meat in the
diet of the anyone suffering from cardiovascular disease.
————————
Soy Can Increase Heart Disease Risk
<http://www.mercola.com/2001/nov/24/soy.htm>
Loma Linda University 2001
Lipoprotein(a) [Lp(a)] was measured in four groups of ambulatory adults ages
17 to 94 at our lifestyle enhancement center for chronic degenerative
diseases because of our preliminary evidence that soy milks made of soy
protein isolate included in the basic total vegetarian diet of unrefined
foods was associated with an elevated LP(a) as measured by enzyme immunoassay
on fasting serum samples.
The authors concluded that powdered soy milk significantly increases the
LP(a) and should be excluded from the diet.
Dr. Mercola’s Comment:
Yet further evidence of the potential danger of eating soy and being a
vegetarian who relies on large amounts of soy products. This research comes
out of the Seventh Day Adventist hospital and therefore would be biased
toward the opposite conclusion, since large percentages of Seventh Day
Adventists are vegetarian.
——————
Soy Protein Diet Increases Lipoprotein (A) Concentrations Compared with
Casein Diet
Am J Clin Nutr March 1999;69:419-425
It’s known that dietary substitution of soy protein for casein decreases LDL-
and increases HDL-cholesterol levels. Danish researchers have now discovered,
however, that soy protein appears to increase lipoprotein (a) levels, which
suggests that use of soy protein might not be advisable in antiatherogenic
diets.
Dr. Mercola’s Comment:
Elevated Lp(a) levels are a very strong risk factor for heart disease. It is
well established yet very few physicians ever check for it in their patients.
I routinely screen for this in all of my heart disease patients. This is an
interesting study that provides us with further evidence that soy is not all
it is cracked up to be.
Most of the positive studies on soy were funded by the edible oil industry
which has strongly vested multi billion dollar incentives to promote soy.
There are only several forms of soy I would recommend. Tempeh and miso are
fine for most people. One half teaspoon twice a day of tofu would also
benefit women with breast cancer as the soy has powerful lectin binders (not
isoflavones) that bind to the breast cancer cells and remove them from the
body.
—————–
The following website discusses the history of soy consumption, with special
reference to the fact that Oriental folk do not eat much soya at all:
http://www.mercola.com/2000/jan/9/truth_about_soy.htm
Just How Much Soy Did Asians Eat?
In short, not that much, and contrary to what the industry may claim soy has
never been a staple in Asia. A study of the history of soy use in Asia shows
that the poor used it during times of extreme food shortage, and only then
the soybeans were carefully prepared (e.g. by lengthy fermentation) to
destroy the soy toxins. Yes, the Asians understood soy all right!
Many vegetarians in the USA, and Europe and Australia would think nothing of
consuming 8 ounces (about 220 grams) of tofu and a couple of glasses of soy
milk per day, two or three times a week. But this is well in excess of what
Asians typically consume; they generally use small portions of soy to
complement their meal. It should also be noted that soy is not the main
source of dietary protein and that a regime of calcium-set tofu and soy milk
bears little resemblance to the soy consumed traditionally in Asia…….
In short, not that much, and contrary to what the industry may claim soy has
never been a staple in Asia. A study of the history of soy use in Asia shows
that the poor used it during times of extreme food shortage, and only then
the soybeans were carefully prepared (e.g. by lengthy fermentation) to
destroy the soy toxins. Yes, the Asians understood soy all right!
Many vegetarians in the USA, and Europe and Australia would think nothing of
consuming 8 ounces (about 220 grams) of tofu and a couple of glasses of soy
milk per day, two or three times a week. But this is well in excess of what
Asians typically consume; they generally use small portions of soy to
complement their meal. It should also be noted that soy is not the main
source of dietary protein and that a regime of calcium-set tofu and soymilk
bears little resemblance to the soy consumed traditionally in Asia….
Perhaps the best survey of what types/quantities of soy eaten in Asia comes
from data from a validated, semi quantitative food frequency questionnaire
that surveyed 1242 men and 3596 women who participated in an annual health
check-up program in Takayama City, Japan. This survey identified that the soy
products consumed were tofu (plain, fried, deep-fried, or dried), miso,
fermented soybeans, soymilk, and boiled soybeans. The estimated amount of soy
protein consumed from these sources was 8.00 ± 4.95 g/day for men and 6.88 ±
4.06 g/day for women (Nagata C et al; J Nutr 1998, 128:209-13)………
The chief concern we have about the consumption of large amounts of soy is
that there is a risk of mega-dosing on isoflavones. If soy consumers follow
the advice of Protein Technologies International (manufacturers of isolated
soy protein) and consume 100 grams of soy protein per day, their daily
genistein intake could easily exceed 200 milligrams per day. This level of
genistein intake should definitely be avoided. For comparison, it should be
noted that Japanese males consume, on average, less than 10 milligrams of
genistein per day (Fukutake M et al; Food Chem Toxicol 1996, 34:457-61)….
Mel Siff
