Antioxidants:
Combating Aging and Disease
By: Sylvia Riley
Wouldn’t we all like to age gracefully (if at all for that matter!)
and ward off the wrinkly signs and ill symptoms for as long as possible.
Keys to longevity may be more accessible than we think, and it appears
our diets play a critical role. Antioxidants are the knights in shining
armor that subjugate the attack of free radicals in the body, the hazardous
molecules that damage cells and procure aging and disease. Though antioxidants
are produced naturally in the body, these decline with age, hence an
increasing need to acquire them from the foods in our diet.
Before examining antioxidants more closely, it is important to take
a look at the free radicals they serve to neutralize.
Free Radicals
Free radicals are created as by-products in our use of oxygen during
metabolism such as the burning of food for energy. They are essentially
oxidant molecules that are missing an electron and seek to restore themselves
by targeting nearby cells in an attempt to recover this electron, potentially
harming enzymes, DNA, proteins and cell membranes in the process. This
damage can mutate cells and alter cell function, increasing the risk
of numerous diseases and chronic conditions including arthritis, diabetes,
cataracts, cancer, heart disease and stroke. Free radical damage is implicated
in the onset of aging and its degenerative symptoms and diseases.
As well as generated within the body, free radicals come from environmental
sources such as pollution, radiation, unhealthy foods, bacteria, viruses,
cigarette smoke and UV light.
Antioxidants
Antioxidants serve to mitigate the harmful effect of free radicals by
giving up an electron and stabilizing them in the process. Although we
produce many of our own antioxidants within the body, food provides an
essential source for these key players of our defense system. Vitamins,
minerals and phytonutrients all have antioxidant properties. The most
common examples include vitamins A, C and E, selenium and zinc, carotenoids,
flavonoids, co-enzyme Q10, alpha-lipoic acid and glutathione.
As there are many different types of free radicals in the body a variety
of antioxidants are required to protect against them. Antioxidants function
best as a team, with each other and other nutrients and phytochemicals,
which is why incorporating a wide range of plant foods into your diet
is recommended. Phytochemical groups such as flavonoids and carotenoids
correspond to the colour, taste and smell attributes of plants, hence
eating a rainbow array of vegetables and fruits can offer a diverse selection
of these potent antioxidants.
Antioxidant Rich Foods
Foods especially high in antioxidants include berries, plums, pomegranates,
oranges, spinach, green tea, avocado, kale, broccoli, peas, onions, grapes
and pure chocolate.
Scientists at the USDA (United States Department of Agriculture) have
developed a rating scale that measures the total antioxidant capacity
of a given food. This is known as the ORAC score (Oxygen Radical Absorbance
Capacity).
Of 40 common fruits and vegetables measured by the USDA, top ranking
scores were those of prunes(5770), raisins (2830), blueberries (2400 – highest
of all fresh foods with other berries close behind), kale (1770), spinach
(1260), Brussels sprouts (980), plums (949), alfalfa sprouts (930), broccoli
florets (890), beetroots (840), oranges (750 ), red peppers (710 ) and
red grapes (739).
Pure cocoa surpasses all these foods with a whopping score of 26,00 units,
more than 10 times the prestigious blueberry (though one is likely to eat
far less in quantity). The extraordinary goji berry from Tibet also has
outstanding antioxidant capacity with a score of 18,500 units; hardly surprising
as they contain 500 times more vitamin C than oranges and even more beta-carotene
than carrots!
According to studies on animals and human blood at the Human Nutrition
Research Center on Aging at Tufts in Boston, high-ORAC foods may slow aging
processes in the body and brain. Results found that high ORAC foods such
as blueberries and spinach could increase the antioxidant power of human
blood by 10-25%, prevent loss of long-term memory and learning ability
in middle-aged rats, and protect rat blood vessels against oxygen damage.
Antioxidants and Aging
As we age, free radical levels rise and yet the body falls short in producing
necessary amounts of antioxidants to meet this challenge. For example,
cells generate more of the oxidants hydrogen peroxide and superoxide, yet
levels of the necessary antioxidant glutathione required to neutralise
these decline. The Free Radical Theory of Aging, first proposed by Harman
in 1954, is supported by cross-species examination of animals with regard
to life span, free radical damage and antioxidant defence. For example,
the white-footed mouse lives about twice as long as the house mouse (8
versus 4 years), and is found to generate less oxidants and have higher
levels of antioxidants. As Beckman and Ames write in The Free Radical Theory
of Ageing Matures (1998), ‘Together, interspecies comparisons of
oxidative damage, antioxidant defences, and oxidant generation provide
some of the most compelling evidence that oxidants are one of the most
significant determinants of life span.’
Very recent evidence comes from a study on dogs at the University of Toronto
by Dr. Dwight Tapp and colleagues who found that ‘old dogs that were
on an antioxidant diet performed better on a variety of cognitive tests
than dogs that were not on the diet. In fact, the dogs eating antioxidant-fortified
foods performed as well as young animals’.
Additional research by Dr. Rabinovitch and his team, studying aging at
the University of Washington, Seattle, found that mice engineered to produce
high levels of an antioxidant enzyme (catalase) lived 20 per cent longer
and had less heart and other age-related diseases than controls.
In light of the role free radicals play in the onset of aging and disease,
it is important to ensure our diets include a rich and diverse supply of
antioxidants. These protective agents can be found abundantly in vegetables,
fruits, nuts and seeds and are particularly high in superfoods.
Sylvia Riley is an author, writer and researcher in the field of natural
health and nutrition. Discover the worlds ultimate superfoods: http://www.miracle-superfoods.com - Article Source: http://www.ArticleBiz.com
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