Vitamin C (Ascorbic Acid) is a very important essential nutrient—that
is, we must obtain it from diet. It is found only in the fruit
and vegetable foods and is highest in fresh, uncooked foods.
Vitamin C is one of the least stable vitamins, and cooking can
destroy much of this water-soluble vitamin from foods.
In recent years, the C of this much-publicized vitamin has
also stood for controversy. With Linus Pauling and others
claiming that vitamin C has the potential to prevent and treat
the common cold, flus, and cancer, all of which plague our
society, concern has arisen in the medical establishment about
these claims and the megadose requirements needed to achieve
the hoped-for results. Some studies suggest that these claims
have some validity; however, there is more personal testimony
from avid users of ascorbic acid than there is irrefutable
evidence. There has also been some recent research that disproves
the claims about treatment and prevention of colds and cancer
with vitamin C. However, in most cases, studies showing vitamin
C to be ineffective used lower dosages than Dr. Pauling recommended.
Overall, vitamin C research is heavily weighted to the positive
side for its use in the treatment of many conditions, including
the common cold.
C also stands for citrus, where this vitamin is found. It
could also stand for collagen, the protein "cement" that is
formed with ascorbic acid as a required cofactor. Many foods
contain vitamin C, and many important functions are mediated
by it as well.
Vitamin C is a weak acid and is stable in weak acids. Alkalis,
such as baking soda, however, destroy ascorbic acid. It is
also easily oxidized in air and sensitive to heat and light.
Since it is contained in the watery part of fruits and vegetables,
it is easily lost during cooking in water. Loss is minimized
when vegetables such as broccoli or Brussels sprouts are cooked
over water in a double boiler instead of directly in water.
The mineral copper, in the water or in the cookware, diminishes
vitamin C content of foods.
Ascorbic acid was not isolated from lemons until 1932, though
the scourge of scurvy, the vitamin C deficiency disease, has
been present for thousands of years. It was first written
about circa 1500 B.C. and then described by Aristotle in 450
B.C. as a syndrome characterized by lack of energy, gum inflammation,
tooth decay, and bleeding problems. In the 1700s, high percentages
of sailors with the British navy and other fleets died from
scurvy, until James Lind discovered that the juice of lemons
could cure and also prevent this devastating and deadly disease.
The ships then carried British West Indies limes for the sailors
to consume daily to maintain health, and thus these sailors
became known as "limeys." Other cultures of the world discovered
their own sources of vitamin C. Powdered rose hips, acerola
cherries, or spruce needles were consumed regularly, usually
as teas, to prevent the scurvy disease.
In earlier times, humans consumed large amounts of vitamin
C in their fresh and wholesome native diet, as apes (another
species that does not make vitamin C) still do. Most other
animals, except guinea pigs, produce ascorbic acid in the
liver from glucose, and in relative amounts much higher than
we get from our diets today. For this reason, Dr. Pauling
and others feel that our bodies need somewhere between 2,000
and 9,000 mg. of vitamin C daily. These amounts seem a little
high to me, given the basic food values of vitamin C. Some
authorities feel we need 600–1,200 mg. daily based on
extrapolations from the historical herbivore, early-human
diet. These levels can be obtained today by eating sufficient
fresh food; a diet that includes foods with high levels of
vitamin C can provide several grams or more per day.
Ascorbic acid is readily absorbed from the intestines, ideally
about 80–90 percent of that ingested. It is used by
the body in about two hours and then usually out of the blood
within three to four hours. For this reason, it is suggested
that vitamin C supplements be taken at four-hour intervals
rather than once a day; or it may be taken as time-released
ascorbic acid. Vitamin C is used up even more rapidly under
stressful conditions, with alcohol use, and with smoking.
Vitamin C blood levels of smokers are much lower than those
of nonsmokers given the same intakes. Other situations and
substances that reduce absorption or increase utilization
include fever, viral illness, antibiotics, cortisone, aspirin
and other pain medicines, environmental toxins such as DDT,
petroleum products, or carbon monoxide, and exposure to heavy
metals such as lead, mercury, or cadmium. Sulfa antibiotics
increase elimination of vitamin C from the body by two to
Some ascorbic acid is stored in the body, where it seems
to concentrate in the organs of higher metabolic activity.
These include the adrenal glands (about 30 mg.), pituitary,
brain, eyes, ovaries, and testes. A total of about 30 mg.
per pound of body weight. We likely need at least 200 mg.
a day in our diet to maintain body stores—much more
if we smoke, drink alcohol, are under stress, have allergies,
are elderly, or have diabetes.
Vitamin C is a very complex and important vitamin. The recommended
amounts vary more widely than those for any other nutrient,
ranging from 100–80 or 100 grams daily, depending on
the condition. C is also the most commonly supplemented vitamin
among the general public, because of either the popular press
or its good effect, or because of the other common C—the
Sources: The best-known sources of
vitamin C are the citrus fruits—oranges, lemons, limes,
tangerines, and grapefruits. The fruits with the highest natural
concentrations are citrus fruits, rose hips, and acerola cherries,
followed by papayas, cantaloupes, and strawberries. Good vegetable
sources include red and green peppers (the best), broccoli,
Brussels sprouts, tomatoes, asparagus, parsley, dark leafy
greens, cabbage, and sauerkraut. There is not much available
in the whole grains, seeds, and beans; however, when these
are sprouted, their vitamin C content shoots up. Sprouts,
then, are good foods for winter and early spring, when other
fresh fruits and vegetables are not as available. Animal foods
contain almost no vitamin C; though fish, if eaten raw, has
enough to prevent deficiency symptoms.
Natural vitamin C supplements are usually made from rose
hips, acerola cherries, peppers, or citrus fruits. Vitamin
C can be synthesized from corn syrup, which is high in dextrose,
much as it is made from glucose in most other animals' bodies.
Synthetic ascorbic acid, though it can be concentrated for
higher doses than natural extracts, is still usually made
from food sources. Sago palm is another fairly new source
of vitamin C supplements. It is used primarily as a lower
allergenic source than the corn-extracted ascorbic acid.
Functions: One important function
of vitamin C is in the formation and maintenance of collagen,
the basis of connective tissue, which is found in skin, ligaments,
cartilage, vertebral discs, joint linings, capillary walls,
and the bones and teeth. Collagen, and thus vitamin C, is
needed to give support and shape to the body, to help wounds
heal, and to maintain healthy blood vessels. Specifically,
ascorbic acid works as a coenzyme to convert proline and lysine
to hydroxyproline and hydroxylysine, both important to the
Vitamin C also aids the metabolism of tyrosine, folic acid,
and tryptophan. Tryptophan is converted in the presence of
ascorbic acid to 5-hydroxytryptophan, which forms serotonin,
an important brain chemical. Vitamin C also helps folic acid
convert to its active form, tetrahydrofolic acid, and tyrosine
needs ascorbic acid to form the neurotransmitter substances
dopamine and epinephrine. Vitamin C stimulates adrenal function
and the release of norepinephrine and epinephrine (adrenaline),
our stress hormones; however, prolonged stress depletes vitamin
C in the adrenals and decreases the blood levels. Ascorbic
acid also helps thyroid hormone production, and it aids in
cholesterol metabolism, increasing its elimination and thereby
assisting in lowering blood cholesterol.
Vitamin C is an antioxidant vitamin. By this function, it
helps prevent oxidation of water-soluble molecules that could
otherwise create free radicals, which may generate cellular
injury and disease. Vitamin C also indirectly protects the
fat-soluble vitamins A and E as well as some of the B vitamins,
such as riboflavin, thiamine, folic acid, and pantothenic
acid, from oxidation. Ascorbic acid acts as a detoxifier and
may reduce the side effects of drugs such as cortisone, aspirin,
and insulin; it may also reduce the toxicity of the heavy
metals lead, mercury, and arsenic.
Vitamin C is being shown through continued research to stimulate
the immune system; through this function, along with its antioxidant
function, it may help in the prevention and treatment of infections
and other diseases. Ascorbic acid may activate neutrophils,
the most prevalent white blood cells that work on the frontline
defense in more hand-to-hand combat than other white blood
cells. It also seems to increase production of lymphocytes,
the white cells important in antibody production and in coordinating
the cellular immune functions. In this way also, C may be
helpful against bacterial, viral, and fungal diseases. In
higher amounts, ascorbic acid may actually increase interferon
production and thus activate the immune response to viruses;
it may also decrease the production of histamine, thereby
reducing immediate allergy potential. Further research must
be done for more definitive knowledge about vitamin C's actions
in the prevention and treatment of disease.
Uses: There are a great many clinical
and nutritional uses for ascorbic acid in its variety of available
supplements. C for the common cold is indeed used very widely;
its use in the treatment of cancer is more controversial,
probably because of the seriousness of the disease and the
political environment within the medical system—anything
nutritional or alternative in regard to cancer therapy is
looked upon with skepticism by orthodox physicians. For the
prevention of cancer, there is reason for more optimism about
the usefulness of vitamin C (as well as the other antioxidant
nutrients—vitamin E, selenium, beta-carotene, and zinc)
because of its effect in preventing the formation of free
radicals (caused mainly by the oxidation of fats), which play
a role in the genesis of disease.
Given the functions of vitamin C alone, it has a wide range
of clinical uses. For the prevention and treatment of the
common cold and flu syndrome, vitamin C produces a positive
immunological response to help fight bacteria and viruses.
Its support of the adrenal function and role in the production
of adrenal hormones epinephrine and norepinephrine can help
the body handle infections and stress of all kinds. Because
of this adrenal-augmenting response, as well as thyroid support
provided by stimulating production of thyroxine (T4) hormone,
vitamin C may help with problems of fatigue and slow metabolism.
It also helps counteract the side effects of cortisone drug
therapy and may counteract the decreased cellular immunity
experienced during the course of treatment with these commonly
used immune-suppressive drugs.
Because of ascorbic acid's role in immunity, its antioxidant
effect, the adrenal support it provides, and probably its
ability to make tissues healthy through its formation and
maintenance of collagen, vitamin C is used to treat a wide
range of viral, bacterial, and fungal infections and inflammatory
problems of all kinds. I have used vitamin C successfully
in many viral conditions, including colds, flus, hepatitis,
Herpes simplex infections, mononucleosis, measles, and shingles.
Recently, vitamin C has been shown in some studies to enhance
the production and activity of interferon, an antiviral substance
produced by our bodies. To affect these conditions, the vitamin
C dosage is usually fairly high, at least 5–10 grams
per day, but it is possible that much smaller doses are as
effective. Vitamin C is also used to treat problems due to
general inflammation from microorganisms, irritants, and/or
decreased resistance; these problems may include cystitis,
bronchitis, prostatitis, bursitis, arthritis (both osteo-
and rheumatoid), and some chronic skin problems (dermatitis).
With arthritis, there is some suggestion that increased ascorbic
acid may improve the integrity of membranes in joints. In
gouty arthritis, vitamin C improves the elimination of uric
acid (the irritant) through the kidneys. Ascorbic acid has
also been helpful for relief of back pain and pain from inflamed
vertebral discs, as well as the inflammatory pain that is
sometimes associated with rigorous exercise. In asthma, vitamin
C may relieve the bronchospasm caused by noxious stimuli or
when this tight-chest feeling is experienced during exercise.
Vitamin C's vital function in helping produce and maintain
healthy collagen allows it to support the body cells and tissues
and bring more rapid healing to injured or aging tissues.
Therefore, it is used by many physicians for problems of rapid
aging, burns, fracture healing, bedsores and other skin ulcers
and to speed wound healing after in-jury or surgery. Peptic
ulcers also appear to heal more rapidly with vitamin C therapy.
The pre- and postsurgical use of vitamin C supplementation
can have great benefits. With its collagen function, adrenal
support, and immune response support, it helps the body defend
against infection, supports tissue health and healing, and
improves the ability to handle the stress of surgery. Vitamin
A and zinc are the other important pre- and postsurgical nutrients
shown by research to reduce hospitalization time and increase
healing rates, thereby preventing a number of potential complications.
Vitamin C is also used to aid those withdrawing from drug
addictions, addictions to such substances as narcotics and
alcohol, as well as nicotine, caffeine, and even sugar—three
very common addictions and abuses. High-level ascorbic acid
may decrease withdrawal symptoms from these substances and
increase the appetite and feeling of well-being. For this
reason, it may be helpful in some depression and other mental
problems associated with detoxification during withdrawal.
Vitamin C also may reduce the effects of pollution, likely
through its antioxidant effect, its detoxifying help, and
its adrenal and immune support; specifically, it may participate
in protecting us from smog, carbon monoxide, lead, mercury,
Vitamin C is a natural laxative and may help with constipation
problems. In fact, the main side effect of too much vitamin
C intake is diarrhea. For iron-deficiency anemia, vitamin
C helps the absorption of iron (especially the nonheme or
vegetable -source iron) from the gastrointestinal tract. In
diabetes, it is commonly used to improve the utilization of
blood sugar and thereby reduce it, but there is no clear evidence
that regular vitamin C usage alone can prevent diabetes. There
are some preliminary reports that ascorbic acid may help prevent
cataract formation (probably through its antioxidant effect)
and may be helpful in the prevention and treatment of glaucoma,
as well as certain cases of male infertility caused from the
clumping together of sperm, which decreases sperm function.
Vitamin C has a probable role in the prevention and treatment
of atherosclerosis and, thereby, in reducing the risks of
heart disease and its devastating results. It has been shown
to reduce platelet aggregation, a factor important in reducing
the formation of plaque and clots. Ascorbic acid has a triglyceride-
and cholesterol-reducing effect and, more important, may help
to raise the "good" HDL. This action needs further investigation,
though the research is supportive so far. I haven't even mentioned
the prevention of scurvy, which really takes very little vitamin
C, about 10 mg. per day. This disease used to be a big concern
and was often fatal unless the victim ate some citrus or other
fresh fruit and vegetables containing a small amount of vitamin
I do not really want to approach the cancer and vitamin C
issue; it deserves a book by itself. However, if we closely
analyze the functions (antioxidant, immune support, interferon,
tissue health and healing) that vitamin C performs in the
body, along with the still mysterious influences of higher-dose
ascorbic acid intake, we can see how vitamin C may have a
positive influence in fighting and preventing cancer, our
greatest twentieth-century medical dilemma.
Deficiency and toxicity: For most
purposes, vitamin C, or ascorbic acid, in its many forms of
use is nontoxic. It is not stored appreciably in our body,
and most excess amounts are eliminated rapidly through the
urine. However, amounts over 10 grams per day that some people
use and some doctors prescribe are associated with some side
effects, though none that are serious. Diarrhea is the most
common and usually is the first sign that the body's tissue
fluids have been saturated with ascorbic acid. Most people
will not experience this with under 5–10 grams per day,
the amount that is felt to correlate with the body's need
and use. Other side effects include nausea, dysuria (burning
with urination), and skin sensitivities (sometimes sensitivity
to touch or just a mild irritation). Hemolysis (breakage)
of red blood cells may also occur with very high amounts of
vitamin C. With any of these symptoms, it is wise to decrease
There is some concern that higher levels of vitamin C intake
may cause kidney stones, specifically calcium oxalate stones,
because of increased oxalic acid clearance through the kidneys
due to vitamin C metabolism. This is a rare case, if it does
exist, and I personally have not seen, nor do I know any doctors
who have seen, kidney stone occurrence with people taking
vitamin C. Only people who are prone to form kidney stones
or gout should give this any thought. If there is concern,
supplementing magnesium in amounts between half and equaling
that of calcium intake (which should be done anyway with calcium
supplementation) would reduce that risk, at least for calcium-based
stones. I usually suggest using a buffered vitamin C preparation
with calcium and magnesium, which alleviates this concern.
As far as deficiency problems go, the once fairly common
disease called scurvy is very rare these days. However, early
symptoms of scurvy or vitamin C deficiency are more likely
in formula-fed infants with little or no C intake or in teenagers
or the elderly who do not eat any fresh fruits and vegetables.
Smokers with poor diets and people with inflammatory bowel
disease more often have lower vitamin C blood levels. Other
people commonly found to be low in ascorbic acid include alcoholics,
psychiatric patients, and patients with fatigue.
The symptoms of scurvy are produced primarily by the effects
of the lack of ascorbic acid on collagen formation, causing
reduced health of the tissues. The first signs of depletion
may be related to vitamin C's other functions as well, where
deficiency could lead to poor resistance to infection and
very slow wound healing. Easy bruising and tiny hemorrhages,
called petechiae, in the skin, general weakness, loss of appetite,
and poor digestion may also occur. With worse deficiency,
nosebleeds, sore and bleeding gums, anemia, joint tenderness
and swelling, mouth ulcers, loose teeth, and shortness of
breath could be experienced. During growth periods, there
could be reduced growth, especially of the bones. The decrease
in collagen may lead to bone brittleness, making the bones
more fragile. The progression and health of the teeth and
gums are also affected. In breastfeeding women, lactation
may be reduced. With the elderly, vitamin C deficiency could
enhance symptoms of senility. The bleeding that comes from
capillary wall fragility may lead to clotting and increased
risk of strokes and heart attacks.
An important note is that many medical problems have been
found to be associated with low blood levels of vitamin C.
These problems include various infections, colds, depression,
high blood pressure, arthritis, vascular fragility, allergies,
ulcers, and cholesterol gallstones.
Most of these symptoms and problems can be easily avoided
with minimal supplementation of vitamin C or a diet well supplied
with fresh fruits and vegetables. Since the average diet has
much less vitamin C than that of our ancestors, it is important
for us to be aware of our ascorbic acid intake.
Requirements: The RDA for adults is
considered to be 60 mg. We need only about 10–20 mg.
to prevent scurvy, and there is more than that in one portion
of most fruits or vegetables. Infants need 35 mg.; about 50
mg. between ages one and fourteen and 60 mg. afterward are
the suggested minimums. During pregnancy, 80 mg. are required;
100 mg. are needed during lactation. Realistically, between
100–150 mg. daily is a minimum dosage for most people.
Vitamin C needs, however, are increased with all kinds of
stress, both internal (emotional) and external (environmental).
Smoking decreases vitamin C levels and increases minimum needs.
Birth control pills, estrogen for menopause, cortisone use,
and aspirin also increase ascorbic acid requirements. Both
nicotine and estrogen seem to increase copper blood levels,
and copper inactivates vitamin C. In general, though, absorption
of vitamin C from the intestines is good. Vitamin C (as ascorbic
acid) taken with iron helps the absorption of iron (and many
minerals) and is important in treating anemia, but the iron
decreases absorption of the ascorbic acid. Overall, it is
probably best to take vitamin C as it is found in nature,
along with the vitamin P constituents (discovered later)—the
bioflavonoids, rutin, and hesperidin. These may have a synergistic
influence on the functions of vitamin C, although there is
no conclusive research on humans to support this theory.
Vitamin C is the most commonly consumed nutrient supplement
and is available in tablets, both fast-acting and time-released,
in chewable tablets, in powders and effervescents, and in
liquid form. It is available as ascorbic acid, L-ascorbic
acid, and various mineral ascorbate salts, such as sodium
or calcium ascorbate. One of my favorite formulas, which was
developed by Stephen Levine at Nutricology in San Leandro,
California, is a buffered powder made from sago palm that
contains 2,350 mg. of vitamin C per teaspoon, along with 450
mg. of calcium, 250 mg. of magnesium, and 99 mg. of potassium.
It gets into the body quickly and is very easy on and often
soothing to the stomach and intestinal lining. The potassium-magnesium
combination can often be helpful for fatigue, and this formula
is a good vehicle for fulfilling calcium needs.
Vitamin C works rapidly, so the total amount we take over
the day should be divided into multiple doses (four to six)
or taken as a time-released tablet a couple of times a day.
When increasing or decreasing vitamin C intake, it is best
to do so slowly because our body systems become accustomed
to certain levels. Some nutritionists describe a problem of
rebound scurvy in infants, especially when a high amount is
taken by the mother during pregnancy but then the infant gets
very little after birth and so suffers some deficiency symptoms.
I have seen nothing confirming this in the literature. Overall,
though, it is probably wise to reduce vitamin C intake slowly
after taking high amounts, rather than to drop abruptly.
My basic suggestion for vitamin C use is about 2–4
grams per day with a typical active and healthy city lifestyle.
Based on previous levels in our native diets, Linus Pauling
feels that the optimum daily levels of vitamin C are between
2,500 and 10,000 mg. Clearly, requirements for vitamin C vary
and may be higher according to state of health, age (needs
increase with years), weight, activity and energy levels,
and general metabolism. Stress, illness, and injuries further
increase the requirements for ascorbic acid. Many authorities
suggest that we take at least 500 mg. of vitamin C daily to
meet basic body needs.
During times of specific illnesses, especially viral infections,
doctors who use megadose vitamin C treatment suggest at least
20–40 grams daily, some of it intravenously. Vitamin
C has been used safely and effectively in dosages of 10 grams
or more dripped slowly (over 30–60 minutes) into the
blood to reach optimum tissue levels before excretion, so
as to bathe the cells in vitamin C. Some doctors prescribe
what is called "bowel tolerance" daily intake of vitamin C—that
is, increasing the oral dose until diarrhea results and then
cutting back. This level can vary greatly from a few grams
to 100 grams or more. The claim is that our body knows what
we need and will respond by changing the water balance in
the colon when we have had enough. Physician Robert Cathcart
has used vitamin C this way in his practice for years to treat
many problems, with claimed good success; yet, I do not have
the experience to make an adequate conclusion. This practice
does, however, add further mystery to the vitamin C controversy.
More research is definitely needed regarding ascorbic acid,
and new discoveries will likely be made.
Staying Healthy With Nutrition
© Elson M. Haas, M.D.