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Supplements - To Take or Not?
According
to a report in the Journal of the American Medical Association (2002;287:3127-9),
all grown-ups should take a daily multivitamin. Two leading doctors, from the
Harvard University published this new report.
This suggestion was put forth after much research was conducted. The research had proven that if we were to take a multivitamin each day, our chances of getting chronic diseases such as heart disease, cancer and osteoporosis would be greatly reduced.
Here are some
conclusive evidences: -
1. Supplementing with folic acid during the first trimester of pregnancy reduces
the risk of birth defects known as neural tube defects.
2. When Vitamin D is taken with calcium, it reduces the risk of fractures in
elderly women with thin bones (osteoporosis).
3. Supplementing with folic acid, vitamin B6, and vitamin B12 may help to prevent
heart disease by lowering homocysteine levels. (This evidence is strong but
not yet conclusive).
4. Vitamin supplements may reduce the risk of colon and breast cancer.
This proposal of supplementing vitamins daily is still relatively new in the conventional medical arena. However, attitudes are beginning to change and more doctors are beginning to recognize its benefits. In the past, most doctors said that vitamin supplements were not necessary because they believed that the normal American diet provided all the essential nutrients to maintain good health and prevent diseases. Today, as the Harvard researchers point out, this opinion is no longer defensible with the rising number of chronic diseases.
The fact that researchers have now proven that vitamin supplementation can prevent several common chronic diseases goes to show that the average American diet indeed does not provide the optimal amounts of nutrients. If we were to consume too much nutrient-depleted foods such as refined sugar and white flour, we will suffer from vitamin deficiencies. The latter can also arise from other factors such as inadequate intakes of vitamin-rich fruits and vegetables and nutrient losses due to processing, prolonged heating and long term storage of foods.
While vitamin supplementation can help to correct certain deficiencies in our bodies, it is not an adequate substitute for a good diet. In other words, we must still maintain a good and healthy diet while taking in extra vitamins. Whole, unprocessed foods contain a wide array of beneficial substances besides vitamins, such as carotenoids, flavonoids, natural antioxidants and other unidentified compounds. The researchers therefore suggest that the best approach is to eat properly and to take a multivitamin.
The researchers also highlight that as most multivitamins contain iron, it may not be suitable for many men, non-menstruating women and a small proportion of the population with an inherited intolerance to iron (hemochromatosis). As such, these people should consult their family doctors on whether it is appropriate to include iron in their supplement.
Over
the last 50 years, the concept of antioxidants have arisen from hoax
to science. It is now generally believed that antioxidants have the ability
to serve as a rust protector for the body, putting a stop to a process called
oxidation. Important molecules in the body, such as those that form the
walls of arteries, become oxidized when they lose an electron. Once oxidized,
they become unstable and easily break apart, leading to arthrosclerosis.
The culprit is the
free radical. Free radicals are highly reactive molecules, or single
atoms with unpaired electrons, looking for a mate to stabilize themselves. They
steal an electron from the first molecule they encounter, perhaps a cell wall
or a strand of DNA. Antioxidants are molecules that have extra electrons to
donate to free radicals, thereby neutralizing them.
As free-radical damage mounts, cells can no longer perform Optimumly. Tissues
degradation begins, and disease sets in gradually. An excess of free radicals
has been implicated in the development of cardiovascular disease, Alzheimer's
disease, Parkinson's disease and cancer, among others.
Aging itself has
been defined as a gradual accumulation of free radical damage. By
age 50, it is estimated that a large part of our cellular protein has oxidative
damage.
Yet not all free radicals are bad.
Benefits of Free Radical
Free radicals are necessary for life.
The body cannot turn air and food into chemical energy without a chain reaction
at the mitochondria involving energy production and free radicals as its by-product.
Free radicals are also a crucial part of the immune system, attacking foreign
invaders. They help fight against bacteria.
The production of free radicals and destruction of free radicals in a non-harmful
manner is also the result of normal metabolic processes in the body. Endogenous
and exogenous antioxidants mop some of them up. The body hopes to avoid excessive
free-radical production, but it a certain amount is absolutely necessary for
life.
Positive studies on Antioxidants
The job of
antioxidants is to neutralize free radicals. Studies have indicate
fairly consistently that having too few antioxidants is a bad for the body. As early as 1983,
a study published in the British medical journal The Lancet, found that people with low blood levels of
selenium were twice as likely to develop cancer compared with people with normal levels.
In the late 1980s, a landmark study, the Harvard-based Physicians Health Study - which has recorded the
lifestyles of some 50,000 male health professionals for the past 15 years - found that men whose diet is
rich in vitamin were half as likely to develop heart disease compare to those with very low levels of
dietary vitamin E.
It is important to note that although these epidemiological studies suggest an association between
antioxidants and good health, this does not mean that the antioxidants directly caused the improved
health. Furthermore, it should not be concluded that taking antioxidants
improves health in and of itself without a concurrent healthy lifestyle.
Since the mid-1990s, numerous studies have suggested that nutritional supplementation commonly referred
to as RDA ( recommended daily allowance ) should be increased. Skin cancer patients given daily selenium
supplements were twice as likely to survive their cancer as those patients not given selenium, the
Journal of the American Medical Association (JAMA) reported in 1996. This was a well designed ,
multi-center, double-blind, randomized, placebo-controlled study with more than 1,300 patients . The
researchers were so impressed that the study was stopped after six years so that all patients could
benefit from the selenium supplement.
Other studies showed similar positive results. Vitamin E has been shown to postpone the onset of
Alzheimer's symptoms in a small study published in the NEJM in 1997. It has also been shown to slow the
onset of coronary artery disease in a study at the University of Southern California School of Medicine
that was published in JAMA in 1995. Vitamin E also cut the risk of cataracts by half in a 1998 study
published in the journal Ophthalmology.
Vitamin C has its share of supporters as well. It has been shown to reduce oxidative stress in the retina
and deter adult macular degeneration, among other benefits. Extra chromium has been shown to stabilize
sugar imbalance, and extra reduced the risk of prostate, colorectal and lung cancer.
Negative Studies on Anti-oxidants
Over the years, various neutral and even negative reports about the
benefits of antioxidant supplements also surfaced. One study found that Finnish male smokers were
18 percent more likely to develop lung cancer after taking a beta-carotene supplement. This was reported
in NEJM in 1994.
Three years later, The Lancet published a study of about 2,000 men receiving vitamin E alone,
beta-carotene alone, both, or a placebo after suffering their first heart attack. The group taking both
vitamin E and beta-carotene was about twice as likely to die from a second heart attack or heart disease
as the placebo group, and the vitamin E-only group was about 1.5 times as likely to die.
Other studies showed similar negative results. Reputable studies in the mid 1990s show no evidence that
vitamins C and E or beta carotene prevented colorectal cancer or arthrosclerosis. There was also no
evidence that beta carotene alone prevented cancer or heart disease in more than 22,000 physicians over
12 years in one study.
The one consistent finding is that smokers should not take high dose of
beta carotene, with a 28 percent higher incidence of lung cancer as a result.
Who is right? They are all right.
Criticisms naturally flowed back and forth, with the pro-supplement physicians finding methodological
errors in studies casting doubt on pills, and the anti-supplement wing finding similar problems in the
work that seemed to contradict their findings.
Most likely, all these studies might be absolutely right, pointing to the
complexity of the matter - that we don't fully understand the intricate relationship between certain
types of antioxidants and certain types of free radicals at different moments over the course of one's
lifetime.
Each antioxidants is different. They work in different places, at
different times, and in different dosage. Blanket statements or broad conclusions drawn from any study on
either camp will not stand up to scrutiny.
It is important to take a step back and look at the whole process of oxidative stress in relation to the
body as a whole for one to make sense out to the conflicting reports that may surface from time to time.
The traditional cause-and-effect approach of medical and scientific studies works only marginally when
baseline parameters of each antioxidant has yet to be formulated and verified.
Just as extra free radical can be a detriment, extra amounts of antioxidants might be turning into
pro-oxidants , fueling free-radical production and its damage. In other words , too much of something may
not be good. The problem is that no one really knows how much is too much.
Animals , for example, produce vitamin C in an equivalent human dose of about 5 grams a
day. This amount is increased by four times during stress. Humans do not make vitamin C. A reasonable
dose of 1 gram to 3 grams a day is extremely safe and non toxic. Most anti-aging researchers do not
consider this amount excessive. Yet in the lay community where the RDA is only 80 mg a day, the
perception of taking
even 1 gram of vitamin C per day may appear excessive.
Several studies have shown that people who did not get the RDA ( 80 mg) of vitamin C had an increase in
free-radical damage to their DNA. Paradoxically, those who took mega doses (over 5-10 grams a day ) of C
also had an increase in DNA damage, although it is used as an
anti-cancer therapeutic agent in selected cases.
Compounding this is the fact that free radicals have been shown to kill certain cancer cells and thus can
be good for the body in . The picture is complex indeed.
Recall some 30 years ago, our knowledge of
cholesterol is
quite simplistic. HDL cholesterol and LDL cholesterol has just be discovered. Their exact relationship is
still unknown. Physicians were trained to lower cholesterol, and reduction of dietary cholesterol intake
seems a logical and sensible approach. Today, we are aware of "good" HDL cholesterol and the "bad" LDL
cholesterol. More importantly, we know that it is the ratio of the good versus the bad cholesterol that
is the key to optimum health and not the absolute total cholesterol level. We also know now that blood
cholesterol level is more directly related to sugar intake than dietary cholesterol intake. The similar
story can be said about the good
omega-3
fatty acid versus the not so desirable omega 6 fatty acid balance which only 20 years ago was not
known to the best nutritionist. To make things worse, the more we know about these relationships, the
more we realize how much we still don't know. The body is indeed the most miraculous machine on the
planet.
Although the theory of free radical and oxidative stress was first advanced in 1956, we are still in
our infancy stage in its understanding and implication for anti-aging. Each study is trying to
measure a specific parameter, but the very nature of the measurement is difficult to interpret due to our
limited knowledge of how each vitamin works to begin with. Researches
are often left with more empirical observations than conclusions.
The danger lies when one tries to associate observations into
conclusions. In the absence of better data, this is the best we can do, some researchers would
argue. This is a normal process of any research, especially in a subject as complicated as this in its
infancy stages. The smart consumer and physician should take a global
view of the entire body of research and its various observations and deduce a overall logical conclusion
rather than relying on any single research study to make any decision, as any such study by definition at
this stage of our limited knowledge is imperfect.
Conclusion
It should be clear that free radicals are as good as they are bad, and
antioxidants in very high doses (higher than optimum dose) may do the body harm.
The question of whether to take supplements comes down to an
intellectual one. Doctors are split on whether to recommend antioxidant supplements to their
patients. The camps are broken down into those who believe there are not enough data to make blanket
recommendations; those who feel that Americans (particularly children) have such a poor diet that they
need a supplement to ensure adequate levels for basic function; and those who say that anyone can benefit
from increased antioxidants regardless of how healthy the diet is. A smaller camp sees in the reports
about negative effects of antioxidant pills reason enough not to take any.
No amount of scientific data in the next few decades can convince the skeptical
mind that requires absolute proof before taking action.
Our knowledge is in nutritional medicine is growing exponentially. It is conceivable that supplements
might do nothing at all because they can't get to where they are needed, or that antioxidants might not
be the magic beneficial chemical in the food we eat after all.
Whether to wait for more information, knowing that they will be
conflicting from time to time, or to proceed on a prudent and cautious basis, depends on the amount of
time available in one's lifespan.
Prevention of oxidative stress takes time, especially if one lives in a polluted environment. Aging is a
process that starts around age 25 . If you are past age 35 ( where you
have entered the
transition phase of aging ) , and especially if you are past age 45 ( where you have entered the
clinical phase of aging), taking optimum amount ( not mega dose amount ) of nutritional supplements
should be considered seriously.
The Best Strategy is :
1. Start with a healthy Modified
Mediterranean Anti-aging Diet. Fruit and vegetables are rich in
antioxidants, but these plants contain hundreds of other chemicals. Any single chemical or combination of
chemicals might pack the therapeutic punch. Nutrients from food enable the body to make its own
antioxidants. A chemical produced by the body called glutathione is ultimately responsible for
neutralizing free radicals, and the glutathione concentration in cells dwarfs that of the free-radical
scavengers such as vitamin C and E.
2. Fortify with an optimum amount (not mega dose amount) of
anti-oxidants in accordance with the optimum
daily allowance through a balanced nutritional cocktail as an insurance policy to maintain a proper balance with free radical productions if
you are over age 35.
This two-step approach makes most scientific sense at this time.
Related Links Introduction
To Take or Not?
Supplement Facts Table
Optimal Daily Allowance
Men's Optimal Daily Allowance
Women's Optimal Daily Allowance
Nutritional Cocktail
Optimal Dosage Allowance
Dosage Guide
Where to Buy
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