Plant foods have been shown to have "chemopreventive"
properties. Risk of lung cancer in heavy smokers has been shown
to be reduced in populations eating generous amounts of plant foods,
and risk of breast, prostate and other cancers is substantially
lower in populations which consume vegetarian or largely vegetarian
diets. Researchers have identified eight food groups, each of which
has unique cancer-preventing qualities. All eight of the food groups
come from the plant kingdom. Conversely, animal product consumption
is implicated in a host of degenerative diseases including cancer
and heart disease, and animal-source foods in general provide little
or no protection against most health conditions other than starvation.
Protein and Cancer: Milk Causes Cancer in Rats
In our opinion, animal studies are problematic in many ways, and
largely if not completely useless. However, there are people to
whom such studies are very important, and those are the individuals
and organizations which set health policies in the US and elsewhere.
These people look at animal studies, rat studies, primate studies,
etc., and extrapolate with great confidence what these studies tell
us about human health. They make decisions that affect us all based
on such studies, setting health policies and issuing advice and
The most fascinating -- and telling -- thing about all this is
that there are powerful animal studies showing that the primary
protein in milk -- casein -- promotes cancer. Yes,
according to multiple animal studies, milk promotes
For example, in rats exposed to a known liver carcinogen and then
fed levels of casein representing excess protein intake (20% of
calories from animal-source protein), precancerous levels increased
dramatically. Rats fed low animal-protein diets (5% of calories
from animal-source protein) experienced a reduction in precancerous
growths by over 90%. Similar studies with rats consuming excess
vegetable protein (20% of calories from plant-source protein) also
showed a dramatic reduction in precancerous growths -- the opposite
of excess animal-source protein intake. When the "missing" amino
acide, lysene, was added to the plant-source protein, making it
a "complete" protein like animal protein, it had the same impact
as feeding animal protein -- increasing cancer growth. 7
The take home message from these studies was that eating more than
a very minimal amount of protein from animal sources promoted cancer
growth while consuming excess protein levels from plant sources
did not, but in fact reduced precancerous growth.
Why are these studies not only ignored -- but buried -- by the
people who set our nutrition and health policy? The reason can only
be that when such animal studies do not fit what is convenient to
them, they disregard them. (Notable is that 6 of the 11 members
of the USDA Dietary Guidelines Committee, which is responsible for
making nutrition recommendations, receive or have received money
from the meat, dairy, or egg industries. Even the Undersecretary of
Agriculture, who participates in the Committee meetings, has a business
relationship with a dairy-product manufacturer -- the Dannon Institute.)
With the USDA reporting that the average American diet consists
of over 40% dairy products (by weight) as well as significant amounts
of meat, chicken and fish, there would appear to be little mystery
why certain cancers are rampant in the US.
Need to Combine
Plant Foods to get "Complete Proteins?"
Vegetable sources of protein (such as beans, peas, and grains)
were once thought to be deficient in one or more essential amino
acids. However, Western vegetarians rarely show protein deficiency
or even deficiencies in any of the essential amino acids, thus the
outdated belief that vegetarians need to be concerned about combining
certain foods to obtain a balanced profile of amino acids has now
been disproved by research and is universally rejected by scientists.
Part of the reason that vegetarians do not need to “balance” amino
acids is that the body’s requirement for essential amino acids now
appears to be much less important than researchers once believed,
especially in adults. In fact, it is now accepted that protein deficiencies
rarely occur in people who simply eat enough calories.
Can I get
My RDA's from a Veg Diet?
A lacto-vegetarian or lacto-ovo-vegetarian diet can easily meet
the Recommended Dietary Allowances (RDAs) for all vitamins, minerals,
protein, and other nutrients. A varied vegan diet will also ensure
adequate amounts of all nutrients except, perhaps, Vitamin B12,
which is an area where there is some controversy and question. Vitamin
B12 was once abundant in plant foods until the advent of modern
farming and food processing techniques. While Vitamin B12 deficiency
is quite rare in vegans, medical literature has reported isolated
cases of B12 deficiency in some vegans, usually nursing mothers
and very small children. For this reason, and until more is known
about the production and absorption of B12 in the human body, vegans
are advised to find a supplemental source of B12. Vitamin B12 supplements
or B12-fortified soy or rice milks are ideal sources of B12, Vitamin
D, and added calcium. (Certain algae and some fermented soybean
products, such as tempeh and miso, are plant sources of Vitamin
B12, but they contain varying, unreliable amounts, and not all such
forms of B12 can be absorbed by the body.)
Some researchers question the wisdom of current government calcium
recommendations. They note that the Standard American Diet is so
fundamentally flawed that trying to protect our bones by taking
in loads of calcium is like trying to fill a tub with no stopper
by turning up the faucets. In general, world dietary patterns show
that countries where people consume large amounts of calcium are
also countries where people eat enormous amounts of animal protein,
such as in the United States and northern Europe. These countries
also suffer among the world's highest rate of fractures due to osteoporosis,
the disease characterized by weak, porous bones. "The correlation
between animal protein consumption and fracture rates in different
societies is as strong as that between lung cancer and smoking,"
says T. Colin Campbell, professor of nutritional biochemistry at
Eating animal protein, which is high in sulfur-containing amino
acids, requires the body to find a way to buffer the effects of
those amino acids. It does so by releasing calcium from the bones,
literally peeing them away. Robert Heaney, professor of medicine
at the Creighton University School of Medicine and a proponent of
high dairy consumption, nevertheless admits that his research shows
the "single most important determinate" of the rate of
bone gain in young women is not how much calcium they consume, but
how much calcium they consume in relation to animal protein.
The more protein eaten, the more calcium must be consumed to offset
the calcium drain. Unfortunately, most people in the US and Northern
Europe eat well more than double the recommended amount of protein
and more than four or five times the amount of protein actually
needed -- with 70 percent of it coming from animal sources. Hello,
Ovo-lacto-vegetarians can get the Recommended Daily Allowance of
calcium by consuming dairy products, but this is not recommended.
Although many people think of calcium in the diet as good protection
for their bones, this is not at all the whole story. In fact, in
a 12-year Harvard study of 78,000 women, those who got the most
calcium from dairy products actually broke more bones than women
who rarely drank milk.8 Similarly, a 1994
study of elderly men and women in Sydney, Australia, showed that
higher dairy product consumption was associated with increased fracture
risk. Those with the highest dairy product consumption had approximately
double the risk of hip fracture compared to those with the lowest
consumption. 9 A study following adolescent
girls from age 12 through 18 found that the amount of calcium they
ingested made zero difference in development of bone mineral density
during the years when women develop between 40 to 60% of their bone
The bottom line on osteoporosis is that the scientific literature
contains a lot of conflicting conclusions about calcium that have
yet to be reconciled. There are studies showing that vegans or near-vegans
have lower bone mineral density (BMD) than omnivores or ovo-lacto-vegetarians.
T. Colin Campbell, Ph.D. has co-authored a study showing that Chinese
women living in counties with low dairy consumption have lower BMD
than women in counties with higher dairy intake.
10 However, it has not been shown that these women were more
susceptible to osteoporosis.
The truth is that nobody knows what the adequate level of calcium
intake is for vegans. Given how little is really known, if you are
vegan it may not hurt to try to get something close to the RDA for
calcium. Good vegan calcium sources include collard greens, broccoli,
kale, turnip greens, tofu prepared with calcium, and fortified beverages
including orange juice, soy or rice milk (check the labels).
Osteoporosis runs rampant through Western civilization with our
elderly fracturing their spines and hips at an unprecedented rate.
Conventional wisdom teaches us that we are not getting enough calcium
and exercise, that we are smoking too much or drinking too much
coffee or, in the case of women, that we lack estrogen. A closer
examination of the evidence would agree that these are contributing
factors, but the primary culprit lies elsewhere.
The women of Bantu who are over 60 years of age do not have osteoporosis.
They have a huge calcium drain, having an average of 10 children
and nursing each child for 14 months. Their diet includes 440 mg
of calcium per day, half of our recommended daily allowance.11-12
They are protected because they eat only 50 gm of protein daily.
When they move to civilization and their protein intake increases
and they develop osteoporosis.13 The mechanism
of this is further clarified by viewing the Eskimo diet.14
The Eskimo consumes a diet that is high in protein (250 to 400 gm
per day) and a diet high in calcium (2000 mg per day); yet, despite
much physical activity, they have one of the highest rates of osteoporosis.15
These two contrasting cultures of the Bantu and the Eskimo illustrate
the osteoporotic effect of a high protein diet. Ammonia and urea
(the breakdown products of protein) initiate a calcium diuresis,
the mechanism of which is still not clearly understood.16
During the past 25 years this observation has been increasingly
scientifically documented, but poorly publicized. A long-term study
noted a negative calcium balance in persons daily ingesting 75 gm
of protein despite a daily intake of 1400 mg of calcium. 17
The conclusion of Allen et al.: "Our data indicate that high
protein diets cause a negative calcium balance to occur even in
the presence of more than ad equate dietary calcium. Osteoporosis
would seem to be an inevitable outcome of continued consumption
of a high protein diet."
Millions of Americans have osteoporosis, accounting for 190,000
hip fractures annually. 18 Fifteen thousand
women die each year as a result of hip fractures. Despite such data,
osteoporosis is unknown in many countries around the world except
in Western civilization, which consumes two to three times more
protein than required. It would appear that osteoporosis is a disease
of chronic dietary protein excess. 19
The dairy industry has spent millions of dollars attempting to
promote the idea that dietary calcium intake is the key to preventing
osteoporosis. However, this is little more than a self-serving advertising
One scientifically proven way to prevent osteoporosis and increase
Bone Mineral Density (BMD), whether you're vegetarian, vegan or
omnivore is called weight-bearing exercise. Studies of people working
out with weights have shown dramatic increases in BMD, even in individuals
in their 70s and older. (Consult with Joyce
Vedral, Ph.D., an exercise specialist who developed a program
using small hand weights and who, at age 56, has 200% greater BMD
of the average woman her age, and 130% higher BMD than a young woman.
Along with diet, regular exercise is key to maintaining good health
over a lifetime.)
As mentioned, other factors with significant impact in promoting
calcium loss include sodium, caffeine, and tobacco intake.
In conclusion, vegans often consume products supplemented with
vitamin B-12 and calcium, just as non-vegetarians consume foods
supplemented with vitamins, calcium and other nutrients. (Milk,
for example, has Vitamin D added during the treatment process it
must go through in attempting to make it suitable for human consumption.)
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