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Rose Hips has all the Vitamin C that a person needs! It is good as
a salve for muscle cramps; use in almost every condition or disease;
prevents and treats infections of all kinds; curbs stress; prevents
cancer.
Vitamin C is required for the synthesis of collagen, an important structural
component of blood vessels, tendons, ligaments, and bone. Vitamin C
also plays an important role in the synthesis of the neurotransmitter,
norepinephrine. Neurotransmitters are critical to brain function and
are known to affect mood. In addition, vitamin C is required for the
synthesis of carnitine, a small molecule that is essential for the transport
of fat to cellular organelles called mitochondria, for conversion to
energy (1). Recent research also suggests that vitamin C is involved
in the metabolism of cholesterol to bile acids, which may have implications
for blood cholesterol levels and the incidence of gallstones.
Vitamin C is also a highly effective antioxidant. Even in small amounts
vitamin C can protect indispensable molecules in the body, such as proteins,
lipids (fats), carbohydrates, and nucleic acids (DNA and RNA) from damage
by free radicals and reactive oxygen species that can be generated during
normal metabolism as well as through exposure to toxins and pollutants
(e.g. smoking). Vitamin C may also be able to regenerate other antioxidants
such as vitamin E.
Until recently, the results of most studies indicated that low or deficient
intakes of vitamin C were associated with an increased risk of cardiovascular
diseases and that modest dietary intakes of about 100 mg/day were sufficient
for maximum reduction of cardiovascular disease risk among nonsmoking
men and women.
First National Health and Nutrition Examination Study (NHANES I) Epidemiologic
Follow-up Study. This study found that the risk of death from cardiovascular
diseases was 42% lower in men and 25% lower in women who consumed more
than 50 mg/day of dietary vitamin C and who regularly took vitamin C
supplements, corresponding to a total vitamin C intake of about 300
mg/day.
Results from the Nurses’ Health Study, based on the follow-up
of more than 85,000 women over 16 years, suggests that higher vitamin
C intakes may be cardioprotective. In this study, vitamin C intakes
of more than 359 mg/day from diet plus supplements or supplement use
itself were associated with a 27-28% reduction in CHD risk. However,
in those women who did not take vitamin C supplements, dietary vitamin
C intake was not significantly associated with CHD risk.
More recently, a pooled analysis of 9 prospective cohort studies, including
more than 290,000 adults who were free of CHD at baseline and followed
for an average of 10 years, found that those who took more than 700
mg/day of supplemental vitamin C had a 25% lower risk of CHD than those
who did not take vitamin C supplements.
Data from the National Institutes of Health (NIH) indicate that plasma
and circulating cells in healthy, young subjects became fully saturated
with vitamin C at a dose of about 400 mg/day.
With respect to vitamin C and cerebrovascular disease, a prospective
study that followed more than 2,000 residents of a rural Japanese community
for 20 years found that the risk of stroke in those with the highest
serum levels of vitamin C was 29% lower than in those with the lowest
serum levels of vitamin C (15). Additionally, the risk of stroke in
those who consumed vegetables 6-7 days of the week was 54% lower than
in those who consumed vegetables 0-2 days of the week.
A number of case-control studies have investigated the role of vitamin
C in cancer prevention. Most have shown that higher intakes of vitamin
C are associated with decreased incidence of cancers of the mouth, throat
and vocal chords, esophagus, stomach, colon-rectum, and lung.
A prospective study of 870 men over a period of 25 years found that
those who consumed more than 83 mg of vitamin C daily had a striking
64% reduction in lung cancer compared with those who consumed less than
63 mg per day.
In the Nurses' Health Study, pre menopausal women with a family history
of breast cancer who consumed an average of 205 mg/day of vitamin C
from foods had a 63% lower risk of breast cancer than those who consumed
an average of 70 mg/day.
In the Swedish Mammography Cohort, women who were overweight and consumed
an average of 110 mg/day of vitamin C had a 39% lower risk of breast
cancer compared to overweight women who consumed an average of 31 mg/day.
A number of observational studies have found increased dietary vitamin
C intake to be associated with decreased risk of stomach cancer, and
laboratory experiments indicate that vitamin C inhibits the formation
of carcinogenic compounds in the stomach. Infection with the bacteria,
helicobacter pylori (H. pylori) is known to increase the risk of stomach
cancer and also appears to lower the vitamin C content of stomach secretions.
Decreased vitamin C levels in the lens of the eye have been associated
with increased severity of cataracts in humans. Some, but not all, studies
have observed increased dietary vitamin C intake and increased blood
levels of vitamin C to be associated with decreased risk of cataracts.
In a study of 747 older men, blood lead levels were significantly higher
in those who reported total dietary vitamin C intakes averaging less
than 109 mg/day compared to men who reported higher vitamin C intakes.
A much larger study of 19,578 people, including 4,214 children from
6 to 16 years of age, found higher serum vitamin C levels to be associated
with significantly lower blood lead level. An intervention trial that
examined the effects of vitamin C supplementation on blood lead levels
in 75 adult male smokers found that 1,000 mg/day of vitamin C resulted
in significantly lower blood lead levels over a 4-week treatment period
compared to placebo. A lower dose of 200 mg/day did not significantly
affect blood lead levels, despite the finding that serum vitamin C levels
were not different than those of the group that took 1,000 mg/day.
The ability of blood vessels to relax or dilate is compromised in individuals
with arteriosclerosis. The damage to the heart muscle caused by a heart
attack and damage to the brain caused by a stroke is related, in part,
to the inability of blood vessels to dilate enough to allow blood flow
to the affected areas. The pain of angina pectoris is also related to
insufficient dilation of the coronary arteries. Treatment with vitamin
C has consistently resulted in improved dilation of blood vessels in
individuals with atherosclerosis as well as those with angina pectoris,
congestive heart failure, high cholesterol, and high blood pressure.
Improved blood vessel dilation has been demonstrated at a dose of 500
mg of vitamin C daily.
Several studies have demonstrated a blood pressure lowering effect of
vitamin C supplementation. One recent study of individuals with high
blood pressure found that a daily supplement of 500 mg of vitamin C
resulted in an average drop in systolic blood pressure of 9% after 4
weeks. It should be noted that those participants who were taking antihypertensive
medication continued taking it throughout the 4-week study. Because
the findings regarding vitamin C and high blood pressure have not yet
been replicated in larger studies it is important for individuals with
significantly high blood pressure to continue current therapy (medication,
lifestyle changes, etc.) in consultation with their health care provider.
Studies in the 1970's and 1980's conducted by Linus Pauling and colleagues
suggested that very large doses of vitamin C (10 grams/day intravenously
for 10 days followed by at least 10 grams/day orally indefinitely) were
helpful in increasing the survival time and improving the quality of
life of terminal cancer patients. However, two randomized placebo-controlled
studies conducted at the Mayo clinic found no differences in outcome
between terminal cancer patients receiving 10 grams of vitamin C/day
orally or placebo. There were significant methodological differences
between the Mayo Clinic and Pauling's studies, and recently, two researchers
from the NIH suggested that the route of administration (intravenous
versus oral) may have been the key to the discrepant results. Intravenous
(IV) administration can result in much higher blood levels of vitamin
C than oral administration, and levels that are toxic to certain types
of cancer cells in culture can be achieved with intravenous but not
oral administration of vitamin C. Thus, it appears reasonable to reevaluate
the use of high-dose vitamin C as cancer therapy.
V vitamin C should not be used in place of therapy that has been demonstrated
effective in the treatment of a particular type of cancer, for example,
chemotherapy or radiation therapy. If an individual with cancer chooses
to take vitamin supplements, it is important that the clinician coordinating
his or her treatment is aware of the type and dose of each supplement.
While research is underway to determine whether combinations of antioxidant
vitamins might be beneficial as an adjunct to conventional cancer therapy,
definitive conclusions are not yet possible.
A 16-year study of 85,000 women, 2% of whom were diabetic, found that
vitamin C supplement use (400 mg/day or more) was associated with significant
reductions in the risk of fatal and nonfatal coronary heart disease
in the entire cohort as well as those with diabetes. In contrast, a
15-year study of postmenopausal women found that diabetic women who
reported taking at least 300 mg/day of vitamin C from supplements when
the study began were at significantly higher risk of death from coronary
heart disease and stroke than those who did not take vitamin C supplements.
Although a number of observational studies have found that higher dietary
intakes of vitamin C are associated with lower cardiovascular disease
risk, randomized controlled trials have not found antioxidant supplementation
that included vitamin C to reduce the risk of cardiovascular disease
in diabetic or other high-risk individuals.
It is possible that genetic differences may influence the effect of
vitamin C supplementation on cardiovascular disease. When the results
of one randomized controlled trial were reanalyzed based on haptoglobin
genotype, antioxidant therapy (1000 mg/d vitamin C + 800 IU/d vitamin
E) was associated with improvement of coronary atherosclerosis in diabetic
women with two copies of the haptoglobin 1 gene but worsening of coronary
atherosclerosis in those with two copies of the haptoglobin 2 gene.
The significance of these findings is not entirely clear, but they suggest
that there may be a subpopulation of people with diabetes who will benefit
from antioxidant therapy while others may not benefit or could actually
be harmed. Since randomized controlled trials have not found that supplementation
with vitamin C is beneficial in preventing or treating heart disease
in individuals with diabetes, individuals with diabetes should avoid
consuming more than 250 mg/day from vitamin C supplements until more
research is available. Since vitamin C intake from foods was not associated
with increased mortality from cardiovascular disease, there is no reason
to limit the intake of vitamin C-rich fruits and vegetables.
In the past 30 years, numerous placebo-controlled trials have examined
the effect of vitamin C supplementation on the prevention and treatment
of colds. A meta-analysis of 30 placebo-controlled prevention trials
found that vitamin C supplementation in doses up to 2 g/day did not
decrease the incidence of colds. However, in a subgroup of marathon
runners, skiers and soldiers training in the Arctic, doses ranging from
250 mg/day to 1 g/day decreased the incidence of colds by 50%. Overall,
the preventive use of vitamin C supplementation reduced the duration
of colds by about 8% in adults and 14% in children. Most of the prevention
trials used a dose of 1 g/day. When treatment was started at the onset
of symptoms, vitamin C supplementation did not shorten the duration
of colds in 7 placebo-controlled trials at doses ranging from 1-4 g/day.
If you develop sores in your mouth, this
is an indication of excessive vitamin C. Discontinue for 7-10 days then
use a smaller dose.
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