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RECOMMENDED CONCISE
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Vitamin C, the water soluble antioxidant
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Vitamin C the water-soluble antioxidant http://healthfully.org/rc/id20.html 9/3/20
Ascorbic acid
dehydroascorbic acid
Ascorbic
acid (vitamin C), and its non-acidic ascorbate forms has two essential functions: as
a vitamin, essential biological co- factor[1]
in 8 essential processes. For health
consequences it is an enzyme in the production of collagen[2];
and as a scavenger for reactive chemicals--especially reactive oxygen. It is
a very effective water-soluble antioxidant,
one that is used as a food preservative.
“Vitamin C is a cofactor in at least eight enzymatic reactions,
including several collagen synthesis reactions…. these reactions are especially important in
wound-healing and in preventing bleeding from capillaries. However, the fact
that the enantiomer
D-ascorbate (not found in nature) has identical antioxidant
activity to L-ascorbate, yet far less vitamin activity, underscores the
fact that most of the function of L-ascorbate as a vitamin relies not on
its antioxidant properties, but upon enzymatic reactions that are stereospecific….
Ascorbic acid is a weak sugar acid structurally related to glucose.
In biological systems, ascorbic acid can be found only at low pH,
but in neutral solutions above pH 5 is
predominantly found in the ionized
form, ascorbate.[3] All [forms] have vitamin C activity,
therefore, and are used synonymously with vitamin C, unless otherwise
specified. The biological role of
ascorbate is to act as a reducing agent,
donating electrons to various enzymatic and a few non-enzymatic
reactions. The one- and two-electron oxidized forms of vitamin C, semi-dehydroascorbic
acid and dehydroascorbic
acid,
respectively, can be reduced in the
body by glutathione and
NADPH-dependent enzymatic
mechanisms. Glutathione
in cells and extracellular fluids helps maintain ascorbate in a reduced state” 2017
Wiki. Glutathione antioxidant functions are
essential for life.
“The
vast majority of animals and plants are able to synthesize vitamin C, through a
sequence of enzyme-driven
steps, which convert monosaccharides
[sugars] to vitamin C. In plants, this is accomplished through the
conversion of mannose
or galactose
to ascorbic acid. In some animals, glucose
needed to produce ascorbate in the liver (in mammals
and perching birds)
is extracted from glycogen
[in cells as needed]… In reptiles
and birds
the biosynthesis is carried out in the kidneys. Most simians consume the vitamin in amounts 10 to 20 times higher than that
recommended by governments for humans. This discrepancy constitutes much of the basis
of the controversy on current recommended dietary allowances. It is countered
by arguments that humans are very good at conserving dietary vitamin C,
and are able to maintain blood levels of vitamin C comparable with other
simians, on a far smaller dietary intake.
Although the body's maximal store of vitamin C is largely determined by
the renal threshold for blood, there are many tissues that maintain vitamin C
concentrations far higher than in blood. Biological tissues
that
accumulate over 100 times the level in blood plasma of vitamin C are the adrenal glands,
pituitary,
thymus,
corpus luteum,
and retina.[40]
Those with 10 to 50 times the
concentration present in blood plasma include the brain,
spleen,
lung,
testicle,
lymph nodes,
liver,
thyroid,
small intestinal
mucosa,
leukocytes,
pancreas,
kidney,
and salivary glands”[4] Wiki.
Evolution has a purpose for apes and guinea
pigs not producing ascorbate, but why?
On the western diet, there might be a need to vitamin C supplement
besides use as an antioxidant. Diabetics
are abnormally low. Testing should be
done for concentration in leukocytes rather than blood level, since blood level
is the amount which the kidney sets.
Taking a supplement every 2 hours can quadruple the blood level, but its
health benefits need further research. High
concentrations give protection from oxidative damage to those tissues listed;
and it “protects phagocytic cells involved in the defense against pathogens” at. Most studies are flawed: they measure
the serum level which reflects
current intake; best is tissue levels which “requires specialized laboratories
which few
are equipped or trained to carry out” Wiki The absorption of vitamin C is tightly
controlled (see cancer below) so that a meg dose (above a gram) is mostly
wasted. Only bats, primates, and
guinea pigs don’t make ascorbate, thus studies of diabetic rats must be viewed
cautiously, since diabetic humans have low ascorbate but not rats. Ascorbate
is a coenzyme in the production of
glutathione, an essential antioxidant. Protection
from oxidation and infection is the logic behind the use of high-dose
supplementation, preferable divided into frequent, small does. Absorption is
highly controlled based on
serum ascorbate. It is
healthful for those who are above their thin-body weight, an indicator of
insulin resistance, metabolic dysfunction caused by mitochondrial dysfunction;
thus over 90% of seniors in the US would benefit.
In
addition to its roles as an antioxidant (note above), ascorbate functions as an electron
donor for 8 different enzymes. It
is
essential for the production of the ubiquitous collagen, the production of
carnitine, the neurotransmitters including the catecholamines norepinephrine
and epinephrine, serotonin, the regulation of histamines, absorption of iron in
the non-heme form found in plants. As an
antioxidant it rejuvenates vitamin E.
Both vitamins are found in LDL, which they protect from oxidative
damage. Ascorbate also clears excess
metal through the process of chelation, and this includes iron, copper.
Ascorbate also reduces the rate of polyunsaturated oxidation by reducing
Fe(III) to the inactive form of Fe(II)—at 1989.
Ascorbate supplement is prudent in large
amounts because of its function as an antioxidant. There is strong evidence
from many sources
for the value of antioxidants, and also on ascorbate’s function as am antioxidant.
I must cherry pick the results because
of pharma’s tobacco science that by
design produces negative results--see
for typical examples. Journals
rely upon pharma; thus, their articles are subject to a sham review--link.
[2]
Collagen is the main structural protein in extracellular space in the various
connective tissues in animal bodies. It
is the main component t in connective tissues forms the matrix for
calcification in the formation of bones, and makes up 25 to 35% of body’s protein.
As coenzyme vitamin C is essential to the production of collagen of
which there are 29 types--Wiki. It is a coenzyme in at least 8 different
pathway producing proteins and other essential compounds.
[3]
“Ascorbate that
completely protects plasma lipids against detectable peroxidative damage
[includes LDL] at,
also.
[4]
Because of transport to those tissues listed, blood measurements of glutathione
level will not significantly rise with oral administration. A second cause is
that “hydrolysis of
glutathione by intestinal and hepatic gama glutamyltransferase, dietary
glutathione is not a major determinant of circulating glutathione” at.
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Antioxidant: “Vitamin
C readily scavenges reactive oxygen and
nitrogen species and may thereby prevent oxidative damage to important
biological macromolecules such as DNA, lipids [LDL,
HDL
& other and proteins]. We found compelling
evidence for antioxidant protection of lipids by vitamin C in biological
fluids, animals, and humans . . .Although the data on protein oxidation in
humans are sparse and inconclusive, the available data in animals consistently
show an antioxidant role of vitamin C.
Vitamin C also reduces redox active transition metal ions in the active
sites of specific biosynthetic enzymes” short,
full,
1999. “In
this
paper, we show that it is indeed ascorbate that completely protects plasma
lipids against detectable peroxidative damage induced by aqueous peroxyl
radicals and that ascorbate is the only plasma antioxidant that can do so.
Plasma devoid of ascorbate, but no other endogenous antioxidant, is extremely
vulnerable to oxidant stress and susceptible to peroxidative damage to lipids …
ascorbate is a physiological antioxidant of major importance for protection
against diseases & degenerative processes caused by oxidant stress” at. This protect
“of
phagystic cells [those that ingest and destroy
foreign particles, bacteria and cell debris] involved in the defense
against pathogen invasion… “ at 86. This
protective
function explains why leucocytes and certain other tissues accumulate up to 100
times the blood level of vitamin C (page 1 above). The oxidative damage along
with glycation
causes the age related diseases that afflict seniors. Ascorbic acid is protective against
hydrogen peroxide
a causal
factor for Parkinson’s
and Alzheimer’s diseases
(a 78% reduction after 3 years). Note
other protective agents include CoQ10,
vitamin E testosterone and estradiol
which work synergistically. Ascorbic acid also reduces glycation of
protein, 1 gram supplement reduced serum glycation by 47%, at 1997.
Asthma: “From our review, we
found a number of studies that support the use of vitamin C in asthma and allergy. Significant results
include positive effects on pulmonary function tests, broncho-provocation
challenges with methacholine or histamine or allergens, improvement
in white blood cell function and
motility, and a decrease in
respiratory infections” at, 1994; “protection
from through antioxidant effect”
at, and 36% lower level ascorbate at.
Cancer: “Epidemiologic evidence of a
protective effect of vitamin C for non-hormone-dependent cancers is strong. Of
the 46 such studies in which a dietary vitamin C index was calculated, 33 found
statistically significant protection, with high intake conferring approximately
a twofold protective effect compared with low intake. Of 29 additional studies
that assessed fruit intake, 21 found significant protection. For cancers of
the esophagus, larynx, oral
cavity, and pancreas, evidence for a protective effect of vitamin C or some
component in fruit is strong and consistent. For cancers of the stomach,
rectum, breast, and cervix there is also strong evidence. Several recent lung
cancer studies found significant protective effects of vitamin C or of foods
that are better sources of vitamin C than of beta-carotene” AJCN,
1991. Linus
Pauling holds that vitamin C functions through
immune functions; thus the use cytotoxic drugs that damage the immune system
(standard chemotherapies) entail minimal benefit from high-does vitamin C. In
1974 Cameron and Campbell preformed a
matching study using patients in a hospital in Scotland which doesn’t use chemotherapy
on terminal patient thus not damaging their immune systems; palliative care was
the norm. One hundred patients were treated
with a daily dose of 10 g of vitamin C with varying dose patterns in an effort
to discover what was the most effective. About half of them received for the
first
several weeks the mega dose intravenously.
Intravenous turned out to be the most effective, since the serum level
is tightly controlled. Later Pauling and
Cameron compared their treated patient group with 1000 untreated patients
matched for key factors. “The mean survival time is more than 4.2 times as great for
the ascorbate subjects (more than 210 days) as for the controls (50 days)” at 1976. However
pharma responded with 2 trial done
for them at the Mayo clinic which by design failed to show benefit (it didn’t
use intravenous ascorbate—2017 review
which also contains the current science as to why Pauling and Cameron
got such dazzling results. This article with highlights is also pasted at
healthfully.
The results clearly indicate that this simple
and safe form of medication is of definite value in the treatment of patients
with advanced cancer” at NAS,
1976; and for
their discussion of the mechanism of prevention of metastatic cancer at ARGIS.[1]
“Our results also suggest that ascorbic acid is a potent anticancer agent for
prostate cancer cells” The Prostate 1998. Resistance
to development of cancer: “The
factors involved in host resistance are
briefly reviewed, and the relationship between these factors and ascorbic acid
metabolism is presented in detail. It is shown that many factors involved in
host resistance to neoplasia are significantly dependent upon the availability
of ascorbate” at 1979. “Here,
we show that a Warburg effect triggered by activation of the hypoxia-inducible
factor (HIF) pathway greatly enhances Vc-induced toxicity in multiple cancer
cell lines…. Through affect upon the cancer metabolism… for the preferential
effect of Vc on cancer cells” at 2014. Pharma
following it pattern did shortly thereafter 2 studies through the Mayo clinic
which failed to show benefit, they didn’t include the intravenous 10 gram then
gram infusion—see 2017. An experiment using IV infusion of vitamin C
for treating cancer in rats had positive results, at 2015, and. A
ketogenic diet and fasting would improve efficacy of mega vitamin C—see (Otto) Warburg effect
2011 and
Thomas Seyfried’s work.
Cardiovascular
Disease, Stroke All
Causes of Mortality: “A meta-analysis of 44 clinical trials has
shown a significant positive effect of vitamin C on endothelial
functions [prevents endothelial
dysfunction
thus
cardiovascular disease] when taken at doses greater than 500 mg per day.
The researchers noted that the effect of vitamin C supplementation appeared to
be dependent on health status, with stronger effects in those at higher
cardiovascular disease risk” Wiki. The same conclusion was drawn in a trial on 17
volunteers, publish AHA. “By inhibiting the oxidative modification of LDL, ascorbate
prevented the uptake and degradation of oxidatively modified LDL by the
scavenger-receptor mechanism of cultured human monocyte derived macrophages” a
step leading to atherosclerosis at 1990.[2] This role explains why LDL carries two
antioxidants, CoQ10 and Vitamin C. “Vitamin C was shown to protect neutrophils
from reactive oxygen species during phagocytosis, to prevent endogenous
oxidative damage to lymphocytes … to
lipids, proteins and DNA, which has been implicated as a major contributing
factor in the development of chronic diseases such as cardiovascular disease,
cancer, and cataract… in the maintenance of endothelial function, mainly by
preventing or reversing endothelial dysfunctions leading to the development of
CVD” at. “The
overall consequence of these antioxidant activities is the beneficial control
of lipid peroxidation of cellular membranes including those surrounding as well
as within intracellular organelles. Intracellular free radical attack on
non-lipid nuclear material may also be diminished, at 1986. For 730 elderly who
completed a dietary record of 7 days in 1973-4, “Mortality from stroke… the
highest third of distribution of vitamin C intake had a relative risk of 0.5
compared with those in the lowest third, after adjustment for age, sex, and
established cardiovascular risk factors” at. “Based
on serum
AA those with normal to high had a lower
cardiovascular disease by 25% and all causes of mortality of 29%” at; “Risk of mortality
in the top ascorbic acid quintile was about half the risk in the lowest
quintile” at.[3] The heart muscles has the 2nd
highest rate of metabolism, and as a consequence their mitochondria leak
reactive chemical at a proportionally higher rate; this explains why of all
organs their myocytes (muscles cells) have the 2nd highest level of
vitamin C.
Diabetes:
a large body of research on low tissue vitamin C in
diabetes
mellitus and its effects upon the production
of collage. Vitamin C is
a cofactor responsible for the
cross linking of the strands of collagen which form its helix structure; that
structure is compromised depending on the degree of diminished amounts of
Vitamin C. Defective collagen the
researchers finds is significantly causals for the comorbidities associated
with diabetes, and stands counter to pharma’s claim of high serum glucose—see articles pasted. Since
diabetes is an extreme form of insulin resistance (hyperinsulinemia) for which
excess fat (lipid droplets) in the pancreas cause inflammation leading to under
production of insulin. Vitamin is a
cofactor in at least 8 other essential process, one of which involves the
restoration of glutathione to its active form.
These two are of particular interest among researchers. In independent
of pharma studies, a mega dose
(gram or more) daily lowers risks of the many pathogenic consequences of
diabetes—as too a ketogenic (low insulin) diet.
Before drugs in the 1960s, type-2 diabetes was managed with a very low
carbohydrate diet, one in which glucose was not secreted in the urine. The older
standard test, using strips, for
diabetes—and should be today.
Dementia, Alzheimer’s
disease,
Parkinson’s,
neuro-degenerative rate is reduce with use of the combination of the fat
soluble vitamin E and the water soluble vitamin C by 66%
Gout (an inflammatory
arthritis caused by high
level of uric acid in the blood which from crystals in joints and tendons, most
often involving the big toe. Affects
about 2% of the Western population.) “
Supplementation
with 500 mg/day of vitamin C for 2 months reduces serum uric acid, suggesting
that vitamin C might be beneficial in the prevention and management of gout and
other urate-related diseases” at 2005. The urea crystal has been shown to
damage the kidneys and thereby through water retention raise blood
pressure.
Immune Enhancing
Function: a number of studies support its promotion of
immune function. “The high cellular
concentration of vitamin C and its rapid decline in plasma and leukocytes
during stress and infection suggests a role in the process of immune response” at. For
the common cold, the results have been a
modest benefit, not enough to justify its usage for this purpose. But for other
infections which result in oxidative
stress, ascorbate is beneficial, at.
Mitochondrial protection:
At the heart of the
health disaster for those populations on the western diet, is mitochondrial
dysfunction caused by the import from the cytosol of proteins and
polyunsaturated fats which have been glycated mainly by fructose. In the mitochondria
these glycated molecules
undergo further reaction causing oxidative damage to mtDNA, membranes, and
proteins for which in excess it causes mitochondrial dysfunction, and this
results in reduced production of ATP. “We found that the oxidized form of vitamin C, dehydroascorbic
acid (DHA), enters mitochondria via facilitative glucose transporter 1
(Glut1) and accumulates mitochondrially as ascorbic acid (mtAA)” at Oct. 2005. By reducing this damage ascorbate reduces the
rate of all the age-related conditions, also called conditions associated with the
western diet. I
take 2-grams a day of calcium ascorbate powder added to my drinking water—gradual
absorption is best..
Rheumatoid arthritis (RH) and Osteoarthritis: “The rapid depletion
of ascorbic acid at sites of inflammation, as in the inflamed rheumatoid joint,
may therefore facilitate proteolytic damage” in an article on the protection
of inflamed rheumatoid joints,1987. “Our studies indicate
that in some cases the intake required to maintain adequate vitamin C levels in
the plasma are much above the average requirement for normal individuals” at 1936, similar 2010. Its dual
role
is in the collagen that forms the matrix for bones and as a protective
antioxidant.
Our western diet with polyunsaturated fats that undergo rancidity, and
the reactive high sugars compounded by insulin resistance are also causal.
Benefits of Ascorbate
high dose supplement: A variety of evidence supports that “immuno-stimulant,
anti-inflammatory, and anti-carcinogenic
effects are well documented in the existing biomedical literature”, at 1984. Ascorbate’s main health
benefit is as a cofactor
in at least eight enzymatic
reactions,
including several collagen
synthesis reactions. . . .Wiki
2017.
For those with health issues on the western high sugar diet who are thus
insulin resistance high dose of ascorbate is likely beneficial, for those on a
low sugar diet, life long, the net benefits of high dose are minuscule or none
existent.
RECOMMENDATIONs: Based upon this review of the literature,
a
general knowledge of cell biology, pathology, & the natural high levels of
vitamin C found in various tissues for protection from oxidative damage, its
low cost, and the lack of side effects; for all these reasons, I recommend 500 mg
per day starting in the
2nd decade and being increased to 1 g in the 5th, and 2
grams in the 7th in the ascorbate form because it one
change the PH of the blood. To acidic I use sodium
ascorbate.[4]
I mix a portion of the powder into tea
or juices. Another choice which I also once
used is the pleasant-tasting chewable sodium ascorbate 500 mg which is
sweetened with sorbitol; available from Costco.
Because it is used as an antioxidant--not vitamin function--the addition
of bioflavonoids is not beneficial to the consumer. The record of research on
bioflavonoids is polluted
with marketing studies to show benefit.
Those studies by pharma and government are designed to show that vitamin
C offers no benefits—a strong sign that it is healthful. Business is a
corrupt master of science. Cheaper
is better because, price matters to most people. Over the internet I purchased
5 kg of sodium
ascorbate and I now take 2 gm daily, and give samples to friends. I also take
the chewable ½ gram sodium ascorbate
sweetened with sorbitol when desiring something sweet.
[1]
Pharma in damage control mode has funded studies using patients who had
received chemotherapy prior to concluded that vitamin C “is not effective
against advanced malignant diseases…,” at 1985, and
there are a number of other articles.
But Pauling used those who immune system had not been compromised by
chemotherapy, because Vitamin C enhances immune functions.
[2]
Actually it is the polyunsaturated triglycerides carried by the LDL that are
because of oxidation pathogenic, at.
[3]
This is weak evidence for the benefit of vitamin C, because it doesn’t control
for the beneficial effect of modify the diet so that fruits are eaten instead
of the standard deserts, and that of the eating fruits are more likely to have
an assortment of diet and lifestyle differences that are healthful. Fruits as
an alternative to other sweets has
a lower effect upon insulin, and hyperinsulinemia (such as in type 2 diabetes)
is associated with significantly higher death rate, for diabetes it is 2
fold.
[4] I
once recommended calcium ascorbate but after watching Dr. Jason Fung lecture on
the lack of benefit of calcium, and modest harm caused by calcium supplements,
I switched to sodium. The sodium warning
is lacking science. Primitive oriental
societies on a traditional diet have intakes of calcium in the range of 300 mg,
yet osteoporosis is unknown—Dr. Jason Fung, 2013. A
second reason is that there are in the sodium ascorbate co-transporters (SVCTs)
and Hexose transporter (GLUTs) thus the absorption of and transport into cells
is favored for the sodium form of ascorbate.
Pharma has corrupted the science
on hypertension.
Irwin Stone recommends 70 mg/kg, or
for 70 kg 4.9 grams daily divided into several smaller doses. The Riordan
Clinic gives intravenous mega doses
Vitamin C megadosage is
a term describing the consumption or injection of vitamin
C (ascorbate)
in doses comparable to the
amounts produced by the livers of most other mammals. Such dosages correspond
to amounts well beyond the current Recommended Dietary Allowance of
90 mg/day, and often well beyond
the Tolerable upper intake level of
2000 mg/day.[1]
[Obviously false since many clinics give
up to about 10 grams a day and Pauling and Cameron used ~10 grams to treat
terminal colon cancer.] Oral dosages are
usually divided and consumed in portions over the day. Injections of hundreds
of grams per day are advocated by some physicians for the treatment of certain
conditions, poisonings, or recovery from trauma. People who practice vitamin C
mega-dosage may consume many vitamin C pills throughout each day or dissolve
pure vitamin C crystals in water or juice and drink it throughout the day.
Historic advocates of vitamin C mega-dosage include Linus
Pauling,
who won the Nobel Prize in Chemistry in
1954. Pauling argued that, due to a non-functional
form of L-gulonolactone oxidase,
an enzyme required to make vitamin C that is
functional in most other mammalian relatives, humans have developed a number of
adaptations to cope with the relative deficiency. These adaptations, he argued,
ultimately shortened lifespan but could be reversed or mitigated by
supplementing humans with the hypothetical amount of vitamin C that would have
been produced in the body if the enzyme were working.
About 70-90% of vitamin C is adsorbed by the body when taken
orally at
normal levels (30–180 mg daily). Adsorption is only about 50% for daily
doses of 1 g. Oral administration, even of mega doses, cannot raise blood
concentration above 0.22 mM.[17]
Humans and other species that do not synthesize vitamin C carry
a
mutated and ineffective form of the enzyme L-gulonolactone oxidase,
the fourth and last step in the
ascorbate-producing machinery. In the anthropoids lineage, this mutation likely
occurred 40 to 25 million years ago. The three surviving enzymes continue to
produce the precursors to vitamin C, but the process is incomplete and the body
then disassembles them. His book How
to Live Longer and Feel Better was a bestseller and advocated taking
more than 10 grams per day orally, thus approaching the amounts released by the
liver directly into the circulation in other mammals: an adult goat,
a typical example of a vitamin-C-producing
animal, will manufacture more than
13,000 mg of vitamin C per day in normal health and much more when
stressed.[19] Stone[23] and
Pauling[24] believed
that the optimum daily
requirement of vitamin C is around 2,300
milligrams for a human requiring 2,500 kcal a
day.
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Disclaimer: The
information, facts, and opinions provided here is not a substitute for
professional advice. It only indicates
what JK believes, does, or would do. Always
consult your primary care physician for medical advice, diagnosis, and
treatment.
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