On Mon, 2 Apr 2001 07:24:22 -0500, Amadeus Schmidt <[log in to unmask]> wrote:
> As we know from nitrogen balance tests, the actual amounts of amino acids
> used for structural purposes are about half of the RDA.
> That means RDA has already a safety factor of 2. Which is necessary to
> provide for the protein quality.
> Todd mentioned some additional purposes some specific amino acids have- with
> some benefits on it. My guess is that the RDA still is on the generous side.
Generous for what? The RDA is designed only to prevent acute deficiency
symptoms, not to promote optimal health over the long term. This is true
for all RDAs.
The protein RDA is based on short term studies, not life-time studies. Over
a short period of time, the body can adapt to an RDA (or lower) level of
protein. This does not mean that the RDA level of protein is ideal for the
long term. The body can run on very small protein intake for short periods
of time, by employing conservation mechanisms. Over the long term, such
mechanisms may break down.
Furthermore, the RDA are calculations based on numerous assumptions and
limited evidence, not the word of God.
Take vit. C for example. The 9th Edition of the NAS-RDA handbook states "A
daily intake of 10 mg of ascorbic acid has been observed to be adequate to
alleviate and cure the clinical signe of scurvy in human subjects.....
However, this amount does not provide for acceptable reserves of the
vitamin." To supposedly provide "adequate reserves" the RDA for vit. C is
only 75 mg per day, but it is well known now that this level of daily intake
will not maximize body stores nor protect against degenerative diseases.
The NAS has itself published research showing that at least 200 mg per day
is required to maximize white blood cell concentrations of C, and to
maximize intraocular concentrations even more is required, more than 500 mg
per day.
So you see that with vit. C, the gap between what is minimally required and
what provides optimal benefits is 20 to 50 fold.
Yet the present RDA for protein only represents a safety factor of 2 fold
over what is absolutely necessary to prevent deficiencies of essential amino
acids over a short term. It does not address benefits that may accrue over
the long term from consuming more than the RDA. As with vitamin C, the
most benefit from protein may come when consuming 2 to 3 times the RDA.
Such as protection against osteoporosis. The Iowa Women's Health study
showed that women who ate only the RDA for protein had a higher rate of hip
fracture than those who ate twice the RDA in the form of animal protein.
The Framingham Osteoporosis project came to a similar conclusion.
In the book Diet and Disease, E. Cheraskin, MD, DMD, W.M. Ringsdorf, DMD,
and J.W. Clark, DDS, reported results of a study wherein 74 wives of
dentists were evaluated for animal protein intake and also asked to fill out
the Cornell Medical Index Health Questionnaire. They researchers found that
the 24 women who consumed only 9 to 66 gm animal protein per day had
significantly more health complaints than those who consumed more than 66
grams per day--and women who consumed at least 86 grams of animal protein
and up to 160 grams per day had the fewest health complaints. This effect
was most pronounced for women over 38 years of age--in that age group, those
with the lowest intake of animal protein had double the health complaints of
those who maintaining the highest animal protein intake.
Vegetarians are fond of citing the RDA for protein, but always neglect to
point out this from the NAS-RDA handbook: "The average concentration of
protein in self-selected diets in most parts of the world provides between 9
and 15 percent of the caloric intake....There is no compelling evidence to
show that such higher intakes are either beneficial or harmful....In
general, foods rich in protein, especially animal protein, are beneficial,
since diets high in animal protein usually contain adequate amounts of
important trace nutrients, such as zinc, iron, and some vitamins." 9th
Edition, p. 51.
What looks good on paper, might not be so in reality, as indicated by the
study I recently posted, which found that vegetarians, and especially
vegans, were deficient in methionine, despite the vegetarian claim that
vegetable foods are adequate sources of all essential amino acids.
>
> Roots tubers and nuts leave you at about 100% RDA protein, if you ate 2500
> kcal (a paleo outdoor or a rural worker may eat even more than the 2500
> kcal, a office worker may eat less).
Again, this is on paper, not necessarily true in practice. For about 10
years, I was a vegetarian, or 99% vegetarian (sometimes eating small amounts
of fish), and during that time I attempted to practice veganism for various
periods, up to several years in a row. When attempting veganism, I could
not consistently eat 2500 calories a day, though that was about what my body
needed to maintain weight. Typically, eating primarily whole grains,
legumes, roots, and other vegetables, I could only get maximally about 2000
calories down, the food was just too bulky--and I daily had heartburn,
indigestion, and painful intestines bloated full of gas, along with
embarrassing noxious flatus, no matter how much (or little) I ate. (At
times I increased the nuts, seeds, and nut butters, but this only added to
the digestive distress.) This is not an uncommon problem among
vegetarians--in fact, gastrointestinal discomfort is so common as to be
legendary among Seventh Day Adventist vegetarians.
Before attempting veganism, I maintained a body weight of 150 to 160 pounds,
only 9 to 10 percent fat. When ever I attempted veganism, I never could
maintain my lean mass; on one of my first attempts, I dropped to 120 to 130
pounds in a short period of time--at 5'9", I looked like a walking stick,
was too weak to do any moderately heavy manual labor, and felt like death
warmed over. A loss of 20 to 30 pounds of lean mass! When practicing
veganism, I never could get my weight to my normal 150--it hovered around
135--I just could not eat enough, and no matter how little or much I ate, I
had digestive problems. In addition, my immune system was weak, I caught
colds easily, several times per year, and had a hard time getting rid of
them, they would hang on for a few weeks.
I ate plenty of whole grains and beans and included some seeds or nuts. I
have been a vegan, and a vegetarian, for long periods of time. Every time I
try to eat whole grains or beans, or eat too much sweet potato, all the
digestive distress I had when a vegetarian returns. This clearly shows me
that my body is not adapted to eating the quantities of whole grains,
legumes, and tubers that would be necessary to provide me with adequate
protein nutrition.
I think many people on this list have had similar experiences and are tired
of hearing your assertions that the human is well adapted to and should eat
large amounts of foods that we know from experience will cause us serious
digestive distress.
>
> Seeds vastly overprovide you with protein (at 2500 kcal).
> Wheat gives you 150% protein (of bad quality). Legumes double the protein
> per kcal (320%) - and make up a protein of superb quality (with wheat).
> If your nutrition bases on seeds, you may come more into the zone where
> oversupply symptoms of protein can arise.
This last sentence is simply false speculation. No one has ever documented
protein 'toxicity' from consumption of seeds!
On the other hand, when Rachel attempted veganism, for several years, her
health deteriorated. She had her diet and blood evaluated by a nutritionist
and lab. The nutritionist was very impressed with her diet, rich in whole
grains and legumes and soy products, including some seeds, which according
to calculations contained 'plenty' of protein and essential amino acids.
However, evaluation of her blood showed that she was lacking in 5 essential
amino acids! She had a weak immune system, had recurring bronchitis, and
lost lean mass. Since eating paleo, she has had no bronchitis.
When I attempted veganism, I once beleived Dr. John McDougall's claim that
if one eats too many beans, one will get protein overload, and if one eats
any nuts or seeds, one will get fat overload, so for periods of time I tried
to live only on whole grains and vegetables, with no beans, nuts or seeds.
When I did that, I got even weaker, and had disturbing problems, such as
this: my skin on heels and fingertips dried out so much that they cracked
and I had fissures 1/8" deep.
The fact is, something may look true on paper, but be proven false in
practice, because it is based on assumptions and calculations. In this
case, the vegetarian protein hypothesis ignores the fact that the human gut
has trouble digesting and extracting protein and amino acids from seeds.
And, even if some people can live as vegans, it does not mean that all can
do so. So, if you are happy being vegan, fine--but when we tried it, we
didn't do well at all.
Again, Rachel and I are not the only ones who have found this to be true, as
I noted already, in a recent post I gave reference to a recent study showing
vegans to be deficient in both B12 and methionine.
Don
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