A Very Simplistic Explanation
of Free Radicals and Anti-Oxidants
This is going to be an extremely simplistic explanation
of Free Radicals and Anti-Oxidants and how they relate to you.
Why would I do that? If you don't recognize harmful
situations, you can't make healthy decisions. It is important for you to
have some understanding of these concepts so you can make conscious,
informed "everyday" decisions concerning your health, and these
include nutrition, exercise, and lifestyle. Research has found many
"things" we felt were safe (and tasty) to ingest, now are found to be
harmful. It takes years for degeneration to take hold and create
negative results in your body.
Free Radicals are considered the "bad
guys" or enemies of the body. In medical terms, they are the "unpaired
electrons". When they are "paired" they don't cause a problem. It's only
when they are alone (unpaired), that they cause damage and need to be
"neutralized/made harmless". In the most simple of explanations, free
radicals cause degenerative conditions, by creating oxidative stress.
Sources of free radicals: any unusual,
foreign "things" coming in the body that aren't supposed to be there:
drugs, toxins, poor food choices such as white flour or sugar, fumes,
smoking, fertilizers, preservatives and additives, chemicals.. The key
in recognizing them is to ask yourself if this is already in your body
and will it help me stay healthy.
Anti-Oxidants: these are considered the
"good guys" in the body. They neutralize the free radicals and keep the
body "balanced", healthy. In relation to oxidative stress, the normal
outcome of too many free radials, I see antioxidants as being against
Sources of anti-oxidants
: your body produces some and
the rest MUST be found in foods eaten. They used to be called vitamins
and come with different names now. Foods that supply them will be your
fruits and vegetables. And for many people this will hint at the fact
that finding them in their diet will be difficult.
Examples of degenerative conditions
caused by oxidative
stress (too many free radicals) are Cancer, Heart Disease, Diabetes Type
I & Type II, Meniere's Disease, Fibromyalgia, Arthritis, Parkinson's,
Lupus, Cataracts, Macular Degeneration, etc.
Below is a four part article
found that really explains the purpose of antioxidants from a medical
and scientific perspective.
Free radicals are atoms
or molecules with unpaired electrons. Once formed, these highly reactive
radicals may cause damage to cells, organelles, and DNA. Antioxidants
are molecules that can safely interact with free radicals and terminate
their reactive behaviour before vital cellular components are harmed.
The body cannot manufacture many antioxidants (including micronutrients
like vitamin C), so they must be supplied by the diet.
ANTIOXIDANTS TUTORIAL, PART 1: What are antioxidants?
Free radicals (pro-oxidants) are atoms or molecules with unpaired
electrons. These highly reactive substances can be formed in a number of
ways, and once formed they may use their reactivity to damage important
cellular components - such as the cell membrane - or macromolecules like
DNA. This damage can lead to mutation, impaired function, and even cell
death. To minimize potential damage from free radicals, the body
utilizes a defense system of antioxidants.
Antioxidants are molecules that can safely interact with free radicals
and terminate their reactivity before vital cellular components are
damaged. Although there are several enzyme systems within the body that
scavenge free radicals, the principle micronutrient (vitamin/mineral)
antioxidants are vitamin E, beta-carotene, vitamin C, and selenium. The
body cannot manufacture these micronutrients, so they must be acquired
by diet. In addition, there are many plant-derived nutrients (phytonutrients)
that can act as powerful antioxidants in the human body.
It is impossible to completely avoid damage from free radicals. Free
radicals arise from sources both inside (endogenous) and outside
(exogenous) our bodies. Oxidants that develop from processes within our
bodies form as a result of normal breathing, metabolism, and
inflammation. Exogenous free radicals form from environmental factors
such as pollution, sunlight, strenuous exercise, smoking, and alcohol.
Unfortunately, no antioxidant system is perfect, so cells and DNA
damaged by oxidation accumulate as we age.
of antioxidants have been associated with reduced risk of some chronic
diseases, in the same way that generous intakes of fruits, vegetables
and grains have been associated with similar health benefits.
ANTIOXIDANTS TUTORIAL, PART 2: Health
benefits of antioxidants
There are many known health benefits of antioxidant intake. Some
scientific examples include the following:
People with high beta-carotene
intakes have about one-third the cancer risk as people with low
beta-carotene intakes. (Peto R. Cancer Surveys 1983;2:327-340.)
People with higher intakes of vitamin
C have about half the risk for many types of cancer when compared to
people with low vitamin C intakes. (Block G. Am J Clin Nutr
People with low intakes of several
antioxidants have more DNA damage than people with generous intakes. (Ames
BN. Metat Res 2001;475:7-20.)
People with the highest intakes of vitamin
C, E, and beta-carotene have a significantly lower risk of lung cancer.
(Yong LC et al. Am J Epidemiol 1997;146:231-43.)
Men who took vitamin E supplements for 10
years or more had a 30% lower risk of bladder cancer. (Michaud DS et al. Am
J Epidemiol 2000;152:1145-53.)
There are over 66 studies showing
cancer-prevention activity of green tea, black tea, and their constituents.
These include cancer reduction in the skin, lung, oral cavity, esophagus,
stomach, liver, pancreas, bladder, small intestine, colon and prostate.
(Lambert JD et al. Am J Clin Nutr 2005;81:284S-291S.)
Elderly people who took both vitamin C and
vitamin E supplements had a decreased risk of death from heart disease as
well as overall mortality. (Losonczy KG, Harris TB, Havlik RJ. Am J Clin
Men who took vitamin supplements had a 70%
lower risk of dying from heart disease and a 50% lower risk of heart attack.
(Meyer F, Bairati I, Dagenasis GR. Can J Cardiol 1996;12:930-934.)
In the Nurses' Health Study involving over
87,000 women, there was a 41% reduction in risk of heart disease for those who
took vitamin E for more than two years. (Stampfer MJ, Hennekens CH, Manson JE,
et al. New Engl J Med 1993;328:1444-1449.)
In the Nurses' Health Study, vitamin C
supplements were also related to a lower risk of heart disease. (Osganian SK et
al. J Am Coll Cardiol 2003;42:246-52.)
In the Health Professionals Follow-Up Study
involving almost 40,000 men, there was a 37% reduction in risk of heart disease
in men who took vitamin E for more than two years. The average intake in the
lowest risk group was 400 IU per day. (Rimm EB, Stampfer MJ. Ascherio A, et al.
New Engl J Med 1993;328:1450-1456.)
To date, 17 human group studies have been
published on flavonoid intake and the risk of coronary artery disease and
stroke. Positive studies have shown reduction in mortality risk of up to 65%.
(Arts ICW and Hollman PCH. Am J Clin Nutr 2005;81:317S-325S.)
The largest and longest study to date, done as
part of the Harvard-based Nurses' Health Study and Health Professionals
Follow-up Study, included almost 110,000 men and women whose health and dietary
habits were followed for 14 years. The higher the average daily intake of fruits
and vegetables, the lower the chances of developing cardiovascular disease.
Compared with those in the lowest category of fruit and vegetable intake (less
than 1.5 servings a day), those who averaged 8 or more servings a day were 30%
less likely to have had a heart attack or stroke. (Joshipura KJ, et al. Ann
Intern Med 2001 Jun 19;134(12):1106-14.)
Other Chronic diseases
Several long-term studies have shown a
reduced risk of cataracts in those who have taken vitamin C and/or vitamin E
supplements for more than 10 years. (Jacques PF et al. Arch Ophthalmol
The Age-Related Eye Disease Study (AREDS) at
NIH found that daily supplementation with antioxidants, zinc, and copper delayed
progression of age-related macular degeneration. (AREDS report no. 8. Arch
Research has shown a significant relationship
between flavonoid intakes and the occurrence of asthma. (Knekt P et al. Am J
Clin Nutr 2002;76:560-8.)
Other research suggests antioxidants may help
support lung function and protect the lungs from oxidative damage. (Schunemann
HJ et al. Am J Respir Crit Care Med 2001;163:1246-55.)
In a study on Alzheimer's disease, high levels
of vitamin E delayed progression of the disease. (Sano M et al. N Engl J Med
Since the average intake of 3 servings or less
of fruits and vegetables fails to provide minimum levels of even basic vitamins,
intakes of the numerous other antioxidants provided by a typical modern diet are
sure to be well under optimal and beneficial levels. It has been established
that a good multivitamin can fill in gaps in missing vitamins, but availability
of broad-spectrum antioxidant supplements has lagged behind.
ANTIOXIDANTS TUTORIAL, PART 3: Sources and
Antioxidants can be vitamins, minerals, enzymes, or plant-derived nutrients
The major vitamin antioxidants are vitamin C, vitamin E and beta-carotene, while
selenium is the major mineral antioxidant. Unfortunately, many researchers and
nutritionists discuss and report on these as if they are the only sources of
antioxidants. However, a thorough examination of antioxidants and their
importance to human health must include a much larger list of compounds
potentially present in a healthy, varied diet. The following list is an example
of the wide variety of phytonutrient antioxidants present in a healthy diet:
||Onions, garlic, leeks, chives
|Carotenoids (e.g. lycopene, lutein, zeaxanthin)
||Tomatoes, carrots, watermelon, kale, spinach
|Flavonoids (e.g. anthocyanadins, resveratrol,
||Grapes, blueberries, strawberries, cherries,
apples, grapefruit, cranberries, raspberries, blackberries
||Green leafy vegetables
||Broccoli, cauliflower, cabbage, Brussels sprouts,
||Legumes (peas, soybeans)
|Isothiocyanates (e.g. sulforaphane)
||Broccoli, cauliflower, cabbage, Brussels sprouts,
||Seeds (flax seeds, sunflower seeds)
||Citrus fruit peels, cherries, nuts
||Whole grains, legumes
|Phenols, polyphenols, phenolic compounds (e.g.
ellagic acid, ferrulic acid, tannins)
||Grapes, blueberries, strawberries, cherries,
grapefruit, cranberries, raspberries, blackberries, tea
The recommendation from the National Cancer
Institute, the U.S.D.A., and nutrition experts is to eat a minimum of 5-13
servings of fruits and vegetables per day depending on your individual caloric
needs. Based on these recommendations, a typical varied diet would provide
approximately 200-600 mg of vitamin C and 10-20 mg (16,000-32,000 IU) of
carotenoids. Additionally, polyphenols " the most abundant antioxidant in the
diet " could have a daily dietary intake as high as 1 gram/day in a mixed,
varied diet of fruits, vegetables, grains, and beverages.
Possible intakes of other phytonutrient antioxidants could include:
Anthocyandins:1,500 mg in two oz. of black
Proanthocyanidins: 100-300 mg/day from red wine
Catechins: 50 mg/day from tea (one cup brewed
green tea " 240-320 mg catechins), chocolate, apples, pears, grapes, red wine
Isoflavones: 50 mg/day from soy foods
Chlorogenic acid: as high as 800 mg/day in coffee
Although it may seem reasonable that a
consistently healthy and varied diet could provide high doses of antioxidants,
the average American gets a total of just three servings of fruits and
vegetables each day. As previously mentioned, dietary guidelines call for five
to thirteen servings. For a person who needs 2,000 calories a day, this
translates into a recommendation of nine servings, or 4½ cups of fruits and
vegetables each day.
The 2001-2002 NHANES survey of dietary intakes shows that 93% of Americans fail
to get even the Estimated Average Requirement (EAR) for vitamin E, let alone the
RDA. More than half of adults fail to get even the average requirement for
vitamin A. About one-third of non-smokers and two-thirds of smokers fall short
on minimum vitamin C requirements. Obviously, since the average intake of 3
servings or less of fruits and vegetables fails to provide minimum levels of
even basic vitamins, intakes of numerous other antioxidants are sure to be well
under optimal and beneficial levels.
It is well-established that a good multivitamin can fill gaps in vitamin and
mineral requirements unmet by a poor diet, but broad-spectrum supplemental
availability of antioxidants has lagged. Although there is much to be learned
about the individual characteristics of the hundreds of potential dietary
antioxidants, it seems reasonable that providing supplements of various
antioxidant classes may also fill nutritional gaps and provide health benefits
potentially missing from the typical western diet.
Advanced levels of
antioxidants are a common thread among nearly every population less prone to
chronic degenerative disease. While high levels of single nutrients and foods
may pose a risk of danger and toxicity, there is no known unsafe level of total
PART 4: Safety of antioxidants
Nutritional supplements have been used and valued by American consumers ever
since vitamins were first discovered and commercialized, beginning largely in
the early decades of the 20th century.
Multivitamin/mineral supplements are an effective means of delivering adequate
amounts of essential nutrients to help people achieve their recommended intakes.
The great majority of dietary supplements, including multivitamins, are safe for
regular use. Despite widespread usage, there have been no specific published
reports of toxicity or adverse effects associated with the proper use of
A series of well-publicized clinical trials utilizing relatively high doses of
single nutrients or combinations of nutrients (such as vitamin E and/or
beta-carotene) in diseased patients have yielded disappointing results, and even
suggested the presence of harm. However, those trials were conducted in patients
with serious illnesses (such as cancer or cardiovascular disease), who were on
multiple medications, or who were smokers. The results of these trials should be
placed in their proper context, including the fact that they are not applicable
to the generally healthy population.
Advanced levels of antioxidants are a common thread among nearly every
population found to be less prone to chronic degenerative disease. As an
example, the Japanese - often cited as an example of longevity - have high
levels of fruit, vegetables, green tea and soy as part of their traditional
diet. Vegetarians have lower levels of heart disease and cancer when compared to
the typical mixed diet, in part due to their generally higher intake of
While high levels of single nutrients and foods may pose a risk of danger and
toxicity, there is no known unsafe level of total antioxidants. As far as we can
tell, as long as they are varied and balanced, the more antioxidants the better.
By Karin Henderson - Nurse, Retired.
I trust you now have a better
understanding of what antioxidants and free radicals are. You also now
understand the damage that the free radicals can create and how that
can lead to oxidative stress. In turn this oxidative stress leads to
degeneration of a body part ( as it does in Multiple
Sclerosis by damaging the myelin sheath: the material that surrounds and
protects your nerve cells in or by allowing too much glucose to remain in
your blood as in diabetes). Oxidative stress seems to be the long term
effect. The obvious solution is to repair or strengthen your immune system.
But would you not ask yourself what the body does at the start? When it
first recognizes an intruder/free radical? If nature is wonderful enough to
provide long term solutions, surely it also provides short term
interventions. It does (if we don't shut it down with "anti-inflammatory
drugs). The inflammatory process is one of nature's immediate protective
mechanisms and involves bringing extra fluid (interstitial) to the area. In
simple terms, it tries to wash out the intruder.
We have some additional articles on the
inflammatory process on the website, they can be found here;
Meniere's Disease and the Inflammatory
Meniere's Disease and The Inflammatory Process and
If you would like to know more about the system we talk about throughout the
use this link to go to the Meniere's System Information page.
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