Before we can appreciate what an antioxidant does for us, we must take another side-trip into chemistry for a glimpse at oxidation and the potential threat it can become to living cells. The encyclopedia tells us that if we could separate out the atoms, oxygen would make up half of the weight of all the rocks in the earth's crust, and eight-ninths of the weight of water. It makes up two-thirds of the weight of the human body.*77
So much for being as light as air. We all know that oxygen is vital to life. In chemical terms "oxidation" is the process in which oxygen combines with an element or compound by means of sharing electrons.
The sun is a nuclear furnace; it radiates a great deal of its energy as visible light. In photosynthesis, plants capture particles (photons) of this high-energy light. Then in small steps, this energy is tamed and parceled out in the rich variety of chemical bonds that make up living substances. The energy is now carried in "excited" electrons, and the molecules made up of atoms which have the excited electrons are said to be oxidized; they can pass their newfound energy to other molecules through the process of oxidation.
Combustion is a familiar form of oxidation; we bring the sun's heat a little closer to home when we build a fire in our fireplace. This is also an example of rapid oxidation at work as oxygen combines with the material to be burned. The glow of firelight released in this process was at one time the sun's brilliant light and potent heat energy captured and stored in the tree which you are burning. Rusting demonstrates slow oxidation as iron and oxygen combine. Stale and rancid food is also the result of oxidation. Oxidation generates light and/or heat energy. You can see and feel its effects simply by standing in sunlight. Every living cell is dependent on oxidation as a means of power production.
Our body's germ killers (phagocytes) keep fired up with oxygen as well.*78 We breathe in oxygen and ingest plant products (either directly or indirectly) which have converted the sun's energy to carbohydrate, fat, and protein. Oxidation drives metabolism and generates heat energy from the food we have eaten. It releases carbon dioxide and water. You may have experienced the results of this process when you feel warmer after having eaten a meal. Thus the sun explodes with energy on a scale of exponential grandeur, and linked by photosynthesis this massive energy is captured in plant food where by means of oxidation on a microscopic scale a mechanism is provided for making the sun's life-promoting power available to us in the way best suited to fuel our trillions of cells. We exhale carbon dioxide and water which plants recycle, thereby perpetuating this efficient and sublime interplay of energy.
However, you will recall that body processes are not random. According to Dr. Milton G. Crane, researcher at Weimar Institute, "Oxidation is meant to occur in a controlled sequence and in a specific setting within the cell chemistry. For oxygen to work in the body, nutrients need to be obtained from the plant products in such a way that they will not be oxidized or burned up at the wrong time or in the wrong place."*79 Dr. Crane uses the analogy that just as it is possible to kindle a fire anywhere in your home to stay warm, a wood stove or fireplace is your best option for keeping the fire contained, controlled, and unable to do damage. Oxidation that is not controlled results in "free" or "toxic" radicals. It was reported in Executive Health, October 1993, that the discovery of free radicals is as important to human health as Louis Pasteur's discovery of germs.
Free radicals are destabilized oxidized molecules which come in a variety of chemical forms. They can attack and destroy bystander molecules, setting off a chain reaction of cellular destruction which eventually assaults our DNA, causing normal cells to become cancerous. Without a way to neutralize these free radicals we would self-destruct. *80 They are believed to be important triggers of damage which leads to heart disease, and they are implicated in over one hundred other diseases. *81 They play a role in the aging process as well. Their discovery has changed the landscape of disease etiology.
We need a correct balance between our food energy sources and the regulators of oxidation. One of the areas where this balance is extremely critical is in fat intake. There is an affinity between these free radicals and certain bonding points in chains of fatty acids. A reaction between a free radical and a fatty acid is dangerous because of its potential to trigger a chain reaction.
You will recall that fatty acids combine to make up the various kinds of lipids which circulate throughout our body. The very presence of an oxidized lipid may interfere with cell membrane structure, the genes, and the cell chemistry which utilizes fatty acids. *82 All fat is a culprit in this process, particularly polyunsaturated vegetable oil. The Omega-3 molecule, highly touted as the beneficial fatty acid in fish oil, is in fact so unstable that it actively encourages the production of free radicals. Omega-3s are found in a more stable form in vegetables, fruit, and legumes. *83 Not only are dangerous chain reactions possible, but when oxygen combines with these fatty acids, it alters or modifies their normal structure. These oxy-fats then upset cell function in a number of ways. In terms of heart disease, there is a modified form of LDL created by this process, which the immune system regards as a foreign substance. Consequently, the immune system activates its removal cells (macrophages) to clear out this unwanted material. The macrophages become full of this oxidized LDL and must themselves become isolated and removed. These bloated, fat-filled cells contribute to plugging arterial walls. As you can imagine, when the immune system is busy trying to cope with the overload of these toxic radicals, it has a diminished capacity to resist the infectious agents which could initiate other illnesses or cancer. *84
Another lipoprotein which may result from excess or oxidized fat has been labeled lipoprotein-a. This fat globule has an enormous tendency to stick inside the walls of weakened vessels. A reevaluation of the Framingham heart study indicated a risk for heart disease from lipoprotein-a which was ten times greater than for high levels of LDL ("bad cholesterol"). *85 Be prepared; it may be that LDLs, now lumped together under the term bad cholesterol, will one day be broken into sub-categories ranging from better to worse with these more recently discovered lipoproteins among them. They may become a part of standard blood lipid testing. With these renegade toxic radicals one thing leads to another, impairing the system at every step along the way.
So just how do vitamins intervene in this oxidation-toxic radical process? Beta-carotene, the precursor or parent of vitamin A, and vitamins C and E act as "antioxidants" because they protect other compounds from being oxidized by acting with oxygen themselves. They shoulder the attack and spare the cell any damage. Vitamins C and E can work together; when vitamin E sustains the attack, vitamin C is there to regenerate E so it can continue the defense. *86
Fifty years ago a Canadian cardiologist reported that eighty percent of his heart disease patients had low blood levels of vitamin C. In 1954 another physician showed that vitamin C could reduce atherosclerotic deposits in his patients' arteries. In May 1992 the University of California, Los Angeles, reported on a study of eleven thousand Americans. They found that increasing the intake of vitamin C cut the death rate from heart disease nearly in half and lengthened life expectancy up to six years. *87 Dr. Matthias Rath, a leading expert in cardiovascular disease and nutrition, believes that there is a vital connection between vitamin C and the sticky, troublesome lipoprotein-a fat globule. *88 Research indicates that vitamin E also plays a protective role in the development of heart disease. According to researchers at the Harvard School of Public Health and Brigham and Women's Hospital in Boston, men and women who regularly take vitamin E supplements can cut the risk of heart attacks by about forty percent. Of the 120,000 men and women studied, those who supplemented daily for two years received the most benefit. (These supplements were ten times the current RDA for Vitamin E.) When taken in the small dietary amounts normally consumed, there was little protective benefit. *89 However, Vitamin E does continue to offer protection as an antioxidant at dietary levels. Vitamin E may be particularly helpful in preventing injurious free radical activity after heart attack or coronary-bypass surgery. Research done on rabbits at Toronto General Hospital showed seventy-eight percent less damage to heart tissue within two hours of a heart attack when the rabbits were injected with vitamin E.*90 Vitamin E also seems to boost the immune system in healthy senior citizens and offers potential for combating a number of environmental pollutants from cigarette smoke to car exhaust.
Vitamin E appears to hold promise for patients with Parkinson's disease as well. It may be a factor in delaying the symptoms of tremor, rigidity and loss of balance.
According to a Canadian Study, vitamins C and E working together appear to reduce the risk of cataracts by fifty percent. It is speculated that if cataract development could be delayed by ten years, about half of cataract surgery could be eliminated. *91
As an antioxidant, beta-carotene is a star performer. Doctors at Harvard Medical School, who have been following twenty-two thousand male physicians as part of a ten-year health study, found that men with a history of cardiac disease who were given beta-carotene supplements every other day suffered half as many heart attacks, strokes, and deaths as those given a placebo. A study is now underway to evaluate forty-five thousand postmenopausal women to determine if the treatment protects women in the same way. Scientists speculate that beta-carotene may help to decrease the impact of toxic radicals on blood lipids like LDL and lipoprotein-a, which are instrumental in the development of heart disease. Special interest has been directed toward the role of beta-carotene in combating cancer. In countries with a diet rich in beta-carotene, incidence of lung, colon, prostate, cervical, and breast cancer is low. That, of course, could be attributed to a number of factors, and there are some studies which indicate that beta-carotene is not the universal cure-all. However, a study at the University of Arizona Cancer Center found that three to six months of daily beta-carotene pills dramatically reduced precancerous mouth lesions in seventy percent of the patients. *92
This marvelous nutrient may not flow from the elusive fountain of youth, but it does factor into the process of aging. According to Dr. Neal Barnard, "There is very little evidence of skin aging before age fifty. What passes for aging is mostly sun damage, or photoaging, which starts early in life."*93 It is those troublesome free radicals which are at work responding to the action of prolonged sun exposure on our skin. Remaining true to the harmonious exchange between plant and man, we find that what was meant to protect the plant from the sun was also designed to protect us. Free radicals form in plant leaves as a result of long hours of sun exposure just as they do in our skin. However, it is the beta-carotene in the plant leaf which removes these free radicals before they are able to inflict damage. That's why green leafy vegetables are generally an excellent source of beta-carotene. Fruit and vegetables which range in color from deep yellow to deep orange are also an excellent source of this nutrient since that is the natural pigment color of carotene. Deep green leaf color is the result of combining carotene with chlorophyll.
What beta-carotene does for the plant it will do for us. As far back as 1926 researchers were exploring the effects of beta-carotene on the skin, and discovered that beta-carotene promoted tanning rather than burning. A diet rich in beta-carotene containing foods or supplements also increases tolerance to sun exposure in people who are extremely sensitive. You may remember all of the attention Retin-A received because of its ability to reverse the signs of aging skin. Retin-A and beta-carotene are part of the same family. *94 Please understand that does not mean that all you have to do is eat a carrot or spinach salad, and then you can spend as much time as you wish in the sun.
The role of antioxidants in disease prevention and treatment is a road still being paved. Currently, we are working with an incomplete picture and a diversity of reports. We need more intervention trials to reliably determine if direct links exist between antioxidants and cancer prevention, and just how this relationship works. Some studies use dosages of vitamin C and beta-carotene that would be possible to obtain from a healthy, conscientious dietary intake from fruit and vegetables. Vitamin E is generally supplemented at greater dosages than dietary equivalents. But many of the present studies utilize large supplemental dosages of these nutrients, and researchers are hesitant to recommend these dosages as part of one's daily routine, since long-term effects are unknown. We've learned much of what we know about the benefits of these nutrients as a result of eating whole foods. It may be that supplements offer dramatic results because most people are woefully short of eating the amount of fruit and vegetables necessary to keep these menacing toxic radical molecules from doing their damage. It may also be that these vitamins are more effective in terms of prevention and in ameliorating precancerous conditions than in short-circuiting a disease process already in motion.
Another factor implicated in the development of free or toxic radicals is iron. Iron is absolutely essential to carry oxygen in the blood, but it can also be a catalyst for damage caused by oxygen. "Just as iron and oxygen work together in the form of oxidation we recognize as rust, something similar happens within the body."*95 Dr. Randall B. Lauffer, a biochemist at Harvard University, indicates that the iron accumulated as one ages really has no place to go; it's unused and waiting to cause trouble. It is thought that this iron-catalyzed free radical damage may be the spark which sets off both heart disease and cancer, in addition to aggravating the aging process. *96
At one time flesh food was considered superior for its contribution of more easily absorbed iron than that which comes from plants. Now science has discovered there is a reason why it is not to our advantage to have stockpiles of iron in our bodies. Iron is sprinkled throughout the plant kingdom, but in a form which prevents an unnecessary buildup. Related to this was the speculation that the reason women had fewer heart attacks prior to menopause was due to estrogen protection. Now it is thought that the fact that women lose iron each month as part of the menstrual cycle may actually be the protective characteristic. Women do not typically have a problem with iron accumulation until after menstruation ceases. This excess disrupts the delicate interplay and balance of nutrients required for optimal health.
One thing we know for a certainty: each cell in the body has an entire antioxidant system that it uses to neutralize free radicals. *97 Since oxidation is a normal, ongoing necessity to fire the metabolism of our food and produce the heat energy which powers the body system, the potential for toxic radical activity is omnipresent. Vitamins and other phyto (plant) chemicals are continually at work to offset these reactions. Therefore it is imperative that we have an abundant supply of these substances circulating throughout our body at all times. This does not necessarily mean taking supplements. Vitamins have become a three-billion-dollar-per-year industry. People seem to think that they need extra protection, or that if a little is good a lot is better. We forget that body chemistry takes place on a microscopic scale and that our total vitamin needs are only about one ounce for every 150 pounds of food we eat. *98 We also seem to be a nation of pill-poppers, but supplements cannot bottle the full complement of chemicals contained in the plant itself, nor do they maintain the proportion or balance with which nature packaged those nutrients in the plant. Not to mention that pills simply cannot mimic the benefits of fiber which come with whole plant foods. Perhaps what holds true for great masterpieces of art also holds true for the artistry of nature's plant creations—a copy is never worth the value of an original.
Lucid arguments can be made on both sides of the supplement vs. nonsupplement controversy. I recognize that depleted, overworked or eroded soils can affect mineral availability to the plant, and one could certainly take issue with the standard which determines our recommended daily allowances for these nutrients, but the bottom line is that we simply need to eat far more plant foods which contain these protective vitamins and phytochemicals, and cut way back on fat. The National Center for Health Statistics reports that a meager nine percent of adults consume five servings of fruits and vegetables a day, and that's a minimum amount, according to the new food pyramid recommendations. It should also be clear that our eating habits have entangled us in the grip of a fat-overload fiasco which pulsates with a disease potential that threatens our very lives. It has been estimated that diet accounts for thirty-five to sixty percent of all cancers, and that tobacco is responsible for another thirty percent; between the two, sixty-five to ninety percent of cancers could be avoided. *99
Why do we do this to ourselves? Yet nature strives with us. The antioxidants, vitamins C, E, and beta-carotene, point out that in spite of this fat fiasco, the abuses and toxins to which we expose our bodies, and the numerous ways in which we work at odds with nature rather than happily cooperating, the body is unrelenting in its attempt to counter the damage. We have looked at only one dimension in which vitamins C, E, and beta-carotene, the parent of vitamin A, work to protect us. Let's turn our attention to their many other functions.
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