Oxidology
Oxidology, the study of oxygen and how our body uses it, has uncovered a fascinating paradox. We all know that humans must have oxygen to survive; however, as our bodies use oxygen, it becomes both a blessing and a curse, because dangerous free radicals are formed. How can oxygen, so necessary for our survival, also be our enemy?
Aerobic Metabolism
Aero-what? Scientists love to put Greek words together. In this case, the words mean something like “air-living change.” So, aerobic metabolism is the process by which our bodies change oxygen into energy. We breathe air in and our lungs take the oxygen out of it. Our blood (specifically the hemoglobin) picks up oxygen and carries it throughout our bodies to each cell. Every cell uses this oxygen to create the energy the cell needs to do its job. That’s the reason all those exercise tapes make such a big deal about aerobic exercise—it’s the kind that boosts your aerobic metabolism, and aerobic metabolism is what makes us go.
Oxygen Depletion: Oxygen is the source of our “life-energy,” but there is a problem. We aren’t getting enough of it. The oxygen-producing forests are being destroyed. Modern industrial technology is polluting the air, further depleting the Earth’s oxygen supply. In the past few hundred years, the oxygen content of our atmosphere has decreased by almost 50 percent.
Most diseases will not thrive in an oxygen-rich environment. That has been proven in the case of cancer. If there is enough oxygen in the cells, cancer and other degenerative diseases cannot exist.
How, then, does this lack of oxygen affect us? It actually causes us to make more free radicals. Boosting oxygen enables our bodies to get rid of free radicals better, but as we keep on living with an oxygen shortage, our metabolism becomes more anaerobic—as if we weren’t breathing at all. Instead of seeking energy from oxygen, our body tries to find other sources and ends up producing all kinds of toxins, all of which increase free radical damage.
Oxidative Damage to the Body
As our bodies turn oxygen into energy, there are by-products that are formed. When you burn wood it produces heat but it produces smoke as a by-product. When your body burns oxygen, it produces energy and by-products called reactive oxygen species, or ROS as we will call them throughout this book. These are the dangerous free radicals, the oxidants that cause oxidative damage to your cells. What makes these by-products toxic is their reactive nature.
If you remember your high school chemistry, you know that atoms are made of neutrons, protons, and electrons, and that electrons like to form bonds in pairs. In reactive oxygen species, there is an unpaired electron in the atom’s outer orbit. That unpaired electron doesn’t like being lonely, so it tries to steal an electron, or maybe a whole hydrogen atom, from something around it. Unfortunately, what is around it is your body. So it tears a little hole in your cell wall, or changes the chemistry of the mitochondria in the cell (the cell’s energy source), or it rips a little piece of DNA out of the nucleus. It doesn’t damage much, but it damages important things. When you multiply that little bit of damage by the millions of free radicals created in your body each second, your body might qualify as a disaster area. Literally, ROS makes your body “rust” or “rot.”
That’s where antioxidants come in. They clean up as many free radicals as they can before damage occurs. Where damage has already happened, they come in to correct the problem. Sometimes the antioxidant gives the ROS an electron to stabilize it. Other times the antioxidant neutralizes the free radical by combining with it to form a different stable compound. There are also antioxidant enzymes that just help the ROS to react with other chemicals to produce safe substances. If you have enough antioxidants (good guys), they win and you stay healthy. If you don’t have enough of the right antioxidants, the “bad guy” free radicals (ROS) win and can cause any of a long list of diseases.
Now, this is not as strange as it sounds. You see it all the time. Have you ever cut up bananas or apples to put in a salad? What happens to them if you set them out in the air for a little while? They turn brown. That is oxidation: free radicals at work. They eat up the cell walls and release the cell fluids, then attack other cells and make a layer of brown mush on the surface of the fruit. How does a caterer avoid this so that the fruit still looks fresh after sitting out for hours? He dips it in lemon juice—vitamin C! He fights oxidative damage with an antioxidant.
Just what is an antioxidant? It can be confusing because we talk about vitamins, minerals, hormones, herbs, chemicals, enzymes, and several types of food, calling them all antioxidants. So what we really mean is that an antioxidant is any substance that can help us fight the rust-rot syndrome caused by free radical damage. Most antioxidants are nutrients derived from foods, but there are a few exceptions, like the hormones melatonin and DHEA, and some of the enzymes your body makes naturally. It really doesn’t matter where the substance comes from as long as it gets rid of free radicals before they can eat us alive.
What Kind of Damage Can These
“Bad Guy” Free Radicals Do?
Plenty! We know that most degenerative diseases are linked to free-radical damage. That means diseases like arthritis, cataracts, diabetes, or any disease where some part of your body is slowly falling apart. They can also attack your brain and central nervous system, causing disorders like Down’s syndrome, multiple sclerosis, and Alzheimer’s disease. ROS have been strongly linked to heart disease and all types of cancer. They also weaken our immune systems in various ways.
Dr. Richard A. Passwater is an internationally renowned author and antiaging researcher. He developed the concept of the “biological synergism of antioxidants” in antiaging. His theory has been proven to be true. Antioxidants, working together, are a key to your health and longevity.
Free radicals have a penchant for attacking certain parts of the cell. Damage to these specific areas creates its own set of problems.
• The cell wall: It is normally porous, allowing nutrients into the cell and letting waste products out. When attacked, it can either rupture and leak or become clogged. Either way, the cell dies prematurely.
• DNA: When free radicals are in the nucleus of the cell, they are apt to attack the genetic material that the cell uses to reproduce itself. Sometimes a free radical will simply attack a gene and mess up this information, which is encoded by subtle chemical bonds. Another type of damage is called cross-linking, in which the DNA is linked to a protein chain so that it cannot replicate at all. These are now seen as the leading mechanisms for cancer growth.
• Blood and tissue lipids: Through a process referred to as lipid peroxidation, fatty cells in the blood and tissues are attacked by hydrogen peroxide or peroxynitrate (both are ROS). An example is low-density (LDL) cholesterol which, when damaged by free radicals altered by your immune system, becomes a bloated, sticky blob that forms an obstructing plaque in the arterial wall. This hardening of the arteries (arteriosclerosis) is a leading cause of heart disease and stroke. Fats that have been peroxidized can also become rancid and toxic to your body.
• Mitochondria: The mitochondria are the powerhouses of the cell, where cellular energy is created. If their reactions are interrupted by free radicals, then the cell does not have energy to work. As cells with low energy accumulate, you eventually have a whole body that is low on energy, tired all the time, and having trouble fighting off disease.
• Lysosomes: The lysosomes are little packets of enzymes inside the cells. These enzymes are designed to eat through anything except the membrane that contains them. When their membrane is ruptured by ROS damage, those enzymes proceed to eat through that cell, and the one next to it, and the one after that—and they produce more free radicals as they go.
This is bad enough. But as time goes on, the damage keeps accumulating. As our immune system gets weaker, the damage even speeds up. Eventually ROS damage produces all of the disorders we associate with aging.
Oxidation and Aging
Free radicals and aging are strongly linked. More than eighty age-related diseases can be alleviated by antioxidants that neutralize oxidant particles. These diseases that we doctors still attribute to your age really have little to do with time, but are directly related to the accumulation of free radical damage in the cells of your body. Age is related to time only by the rate at which oxidative stress is taking its toll on your body. And more important to you, that rate of free radical damage can be changed. Antioxidants are available that will dramatically slow the aging of your body!
As antibiotics in the last fifty years of the twentieth century helped “cure” many infectious diseases, so antioxidants will effect a “cure” of many supposedly incurable diseases in the twenty-first century and slow the process of aging dramatically. This is good news, but few of us, and I include us doctors, have ever heard about this antioxidant revolution. As you will discover if you heed the advice given in this book, there are tremendous benefits to be gained by slowing the aging process, not the least of which are looking and feeling good. If you consider nothing else, consider how much money you and your loved ones will save in doctor and hospital bills.
Aging might be described as that life process in which the healthy cells in your body are slowly but continuously being reduced in number. Aging is not, as is commonly thought, the inevitable “wearing out” of your body parts, as if your body were a car that needed an overhaul. It is the accumulation of damage done to individual cells all over your body that results in the problems we associate with aging. As more and more cells are affected by oxidation, symptoms of aging may not be evident, but the body is losing healthy reserve cells needed to react in emergency situations. When a crisis comes, there is not enough backup strength for that organ or system to function normally. This, in turn, leads to an imbalance in the various organ systems that normally would work together in harmony. As your body’s homeostasis (balanced condition) is disrupted, all systems begin to fail, falling like a house of cards in the wind. Disease and premature death become inevitable. But the scenario can be changed if we deal with oxidative stress before these problems arise.
So, you can see that we don’t age one day at a time; we age one cell at a time. That is good news, because we cannot turn back the clock, but we can prevent free radical damage from continuing to ravage the cells of our bodies. In some instances, we can even reverse this cellular damage. As we continue our discussion, you will see that many degenerative diseases are simply complications of accumulative free radical (oxidative) damage. But we have a choice about how this will affect us. We can choose to fight back.
Glycation and Aging: To be fair, oxidation is not the only issue in aging. Another important factor in aging is the process of glycation. Glycation occurs when proteins react with excess sugar. The resultant damage to the proteins is just as detrimental as free radical damage. These sugar-damaged proteins are called advanced glycation end products, or AGEs, an appropriate acronym since they lead to premature aging. According to Dr. Anthony Cerami, author of The Glycation Hypothesis of Aging, “The formation rate of AGES increases as the blood sugar level increases and with the length of time the level is raised.” The average blood sugar levels tend to rise with increasing age, primarily because our tissues are less sensitive to insulin. So as time passes, our blood sugar level rises, which causes AGEs to form more rapidly. Elevated and/or widely fluctuating blood sugar promotes the damaging cross-linking of collagen and other important proteins that is seen in aging tissue. As this damage continues, it leads to joint problems, loss of energy and muscle strength, decline of mental powers, difficulties with weight control, and a host of other problems we associate with aging.
You can control glycation, too, just as you can control oxidation. The answer is simple, but you may not like it. Sugar is not good for you. Avoid it if at all possible. Never add it to your food. If you must satisfy your sweet tooth, use Stevia, a safe sweetener from the South American “sweet herb” plant. You can cook with it, too. Another way to control your sweet tooth is to satisfy the dietary need that makes you feel that you need something sweet. Chromium picolinate supplementation (200 mcg daily) has proven effective for this by helping the body metabolize fats, carbohydrates, and proteins. It can also give you increased energy and suppress appetite.
Gain Control Over Free Radical Damage
While the damage from oxidation cannot be minimized, the body does have its own means of dealing with the problem of oxidation. The first line of defense against free radicals is a system of enzymes produced by your body to neutralize free radicals. They are superoxide dismutase (SOD), catalase, and glutathione peroxidase. In addition, the body uses antioxidant vitamins, minerals, and substances found in food and herbs to counteract the damaging effect of ROS.
Vitamins A, C, and E are all excellent ROS scavengers. Other important antioxidant substances found in the diet include:
• proanthocyanidins, in grape seeds
• herbs like ginkgo biloba and garlic
• quercetin, found in zucchini, squash, and green tea
• lycopene from tomatoes
• the trace minerals selenium and germanium, and many other naturally occurring substances, some as yet unidentified.
We will learn about these and other antioxidants and how they work in chapter 5.
But how and why do ROS attack cells? And how does the antioxidant system work to counteract this attack? This is best answered by examining each of the toxic species individually.
The Paradox of Oxygen: Now that we know how the by-products of oxygen damage our bodies, we may question the value of exercise, especially aerobic exercise. We have all been told that increasing the oxygen levels in tissues is beneficial to the body and that exercise should consist of at least twenty minutes of elevated heart rate and deep, regular breathing. To explain the paradox of oxygen we must remember that it is not the oxygen that is toxic, but rather the by-products of the metabolism of oxygen, formed as the body utilizes the oxygen. Increasing oxygen levels in the body is good, but we have to help the body deal with the byproducts of using all that oxygen. The oxygen paradox is solved by boosting the antioxidant level in the body to assist the immune system in providing natural scavengers of these free radicals.
Antioxidants fight these toxic free radicals by combining with them, scavenging and eliminating their ability to attack the cell. To support this antioxidant activity, we must have available specific minerals critical to the synthesis of antioxidant compounds. These minerals include copper, iron, magnesium, sulfur, selenium, manganese, and zinc. If these chemical elements are not available in adequate supply, the defense system is compromised and unable to handle the toxic overload. The more oxygen the body is metabolizing, the greater the need for these minerals.
Specific ROS and the Natural Biological
Agents that Protect the Body from
Their Adverse Effects
Superoxide (O2−*)
In the normal activity of the body’s processing of molecular oxygen, the free radical superoxide is formed. Superoxide is nothing more than an oxygen molecule with an extra electron. It’s that extra electron that makes it a free radical. Superoxide is the most common free radical we encounter. Normally, superoxide is rapidly scavenged by the superoxide dismutase (SOD). This enzyme works by catalyzing (speeding along) a reaction between two superoxide molecules and two hydrogen molecules. However, if detoxification is not rapid enough (due to the unavailability of sufficient SOD), the superoxide attempts to regain an electron from any available source. Cell membranes are a favorite target. So are the mitochondria and the chromosomes. So, not only do we have a “bad guy” that may prematurely kill the cell, it may also create a deviant cell which could produce cancer. SOD, the “good guy” here, requires the presence of copper, zinc, and magnesium for its production and proper functioning.
Hydrogen Peroxide (H2O2)
One of the by-products of scavenging the superoxide radicals is hydrogen peroxide. It is not as reactive as superoxide, but it is not friendly either. You are probably aware of how a 5 percent solution of this chemical reacts when you pour it on an open wound. Can you imagine having the full strength stuff trapped inside a cell?
Hydrogen Peroxide is generally destroyed by either the enzyme catalase or glutathione peroxidase. Catalase works in water and glutathione peroxidase works in fat. When they finish, the hydrogen peroxide has been converted to water and oxygen (H2O and O2).
Hydrogen peroxide has been linked to the awakening of the latent Epstein-Barr virus, which in turn has been linked to chronic fatigue syndrome and aging. More startling has been the discovery that hydrogen peroxide has the ability to damage the master DNA template (your very own genetic inheritance) that tells the cells how to duplicate themselves. As with superoxide, these mutations open the door to potential cancer-causing activities (carcinogenesis), Down’s Syndrome,2 and other genetic diseases. Liver cancer has been directly linked to hydrogen peroxide.
One of the problems that you will read a lot about in the pages that follow is lipid peroxidation. Hydrogen peroxide is the chief culprit in that crime, and it causes a plethora of diseases in one way or another.
Selenium and L-cysteine are important in the control of hydrogen peroxide and lipid peroxidation. Both are necessary for the formation and replenishment of glutathione, which is the ultimate scavenger of hydrogen peroxide in fats.
Hydroxyl Radical (HO*)
What happens when there is not enough glutathione or selenium for the antioxidant enzymes to do their job? If hydrogen peroxide is not completely converted to water, the hydroxyl radical, a very toxic free radical, is formed. This conversion of hydrogen peroxide to hydroxyl radicals happens when metals, such as free atoms of iron and mercury, are present. Hydroxyl radicals are also formed during exercise.
The hydroxyl radical is the most highly toxic of the free radicals. It is so dangerous because it is extremely reactive, usually lasting only thousandths of a second before it steals a hydrogen atom from whatever it touches first. So, it damages the cell as fast as it can spread. It may not seem like it could do much damage in so short a time, but the fact is that you don’t have any part in any cell that can afford to give up a hydrogen atom. And it never happens just one molecule at a time, here and there—it happens in millions of molecules at once.
Research has shown that the enzyme methionine reductase has the ability to remove this free radical from our bodies. Another effective scavenger of hydroxyl radicals is injectable amygdalin (vitamin B17—laetrile). This amygdalin is an isolate of almonds, apricots, and plum and cherry pits. Additionally, the proanthocyanidins found in grape seed extract and pine bark extract counteracts this dangerous hydroxyl radical.
Singlet Oxygen (1O2)
Did you know that oxygen exists in more than one form? Normal oxygen, O2, is good for us, yet singlet oxygen, 1O2, can be extremely dangerous. O2 can be a very stable molecule, but if it is exposed to radiation in the form of sunlight, the chemical bonds break and it becomes quite hazardous to your health.
Singlet oxygen is involved in diseases of the joints (arthritis), but most damaging are its effects on the human eye. It can damage the lens, causing cataracts, or the retina, causing macular degeneration. In both cases, it is the exposure of singlet oxygen to light which triggers the ROS damage.
Now, a number of substances have been found to quench singlet oxygen. These include the carotenoids, such as beta-carotene and lycopene. Lycopene is the most potent of all singlet oxygen quenchers. Additionally, the tocopherols (vitamin E), along with the amino acid histidine, can neutralize this free radical. Even cholesterol can act as a scavenger of singlet oxygen.
What Factors Contribute to Increased Production of Free Radicals?
The production of free radicals is 100 percent normal. It goes along with breathing. But there are things that cause us to make more free radicals than we normally would. Here is a short list:
Stress—emotional or physical stress makes you breathe less and burn energy more. Stress feeds on anaerobic metabolism, not oxygen.
Ozone in the air—a great way to produce superoxide.
Auto exhaust—you breathe carbon monoxide and hydrochloric acid instead of oxygen.
Inflammations—your body’s immune system creates free radicals as it fights germs.
Radiation—alters molecules in subtle ways, throwing off free radicals.
Sunlight—a form of radiation.
Impure water—between the impurities left in municipal water supplies and the chemicals used to cover them up, most water is toxic out of the tap. Beware: bottled water may come from the exact same source!
Processed foods—you can’t get nutrients from man-made food, so your body shifts to anaerobic metabolism to try to get something out of it.
Toxic metals—they are in our soil, our water, our air, and they attract free radicals.
Industrial chemicals—in general, man-made chemicals are bad for you.
Drugs—even the “safe” ones the doctor prescribes for you change your ability to metabolize oxygen.
So now we have identified the “bad guys.” There are other free radicals that can show up, but we’ve covered the big four. We also gave you some hints that the war is not lost. There is a way to deal with all oxidative damage: we just have to have the right “good guys” working for us. As long as we have enough antioxidants in our system—that is, if we have the capacity to handle a lot more ROS than we are creating—we can maintain not only health, but youth and vitality as well.
In the next chapter, you will learn about the factors that increase our oxidative stress and how to combat them.