The New Optimum Nutrition Bible
Page 14
Although our lead exposure today may be less than it was in previous decades, lead pollution is still present in the atmosphere (it’s even been found in the polar ice caps) and also comes from water contaminated by lead piping and from flaking paint and paint dust, pesticides, cosmetics, and industrial exposure. When intakes of the essential minerals calcium, zinc, or iron are low, lead becomes that much more toxic. Given that many people are deficient in all three, it’s important to redress the balance through diet and supplements.
Mercury
Mercury is the reason nineteenth-century hatters went mad. By polishing top hats with mercury, they became overloaded with this toxic element, which disturbs brain function and makes you crazy. Mercury is very toxic indeed and small amounts reach us from contaminated foods and from tooth fillings. Of particular concern is fish caught in polluted waters.
Mercury is used in a number of chemical processes, and accidents and illegal dumping have led to increased mercury levels in some areas, including the seashores and lakes of the U.S. Fish, especially larger species like tuna, store the mercury, which we then ingest. Fortunately, tuna is high in selenium, a mercury protector. Mercury has also been used as a constituent of thimerosal, found in diphtheria and hepatitis vaccines. This practice has recently been stopped.
Sadly, owing to widespread pollution, fish are one of our biggest sources of mercury. The larger and fattier, the greater the accumulation—up to two million times the amount found in the water.39 One in twelve American women of childbearing age has potentially hazardous levels of mercury in her blood as a result of consuming fish, according to government scientists.40 As a result, the U.S. Food and Drug Administration recommends that pregnant women don’t eat tuna, shark, swordfish, king mackerel, and tilefish. In the United Kingdom, the Food Standards Agency advises women who intend to become pregnant and those who are pregnant or breast-feeding to limit their consumption of tuna to no more than two medium-size cans or one fresh tuna steak per week. It also advises avoiding shark, swordfish, and marlin altogether.
Mercury is also found in water contaminated by industrial processes and in pesticides, but besides fish, our other most common source of this toxic metal is dental fillings. The mercury in teeth is not totally immobile and it’s possible to detect traces of mercury in the breath of people with mercury fillings. After fillings have been fitted or removed, urinary mercury may also show a slight increase. Sweden has now banned mercury fillings for pregnant women.
Autopsies on brains from AD patients, compared with those of control patients of the same age, have shown raised levels of mercury.41 Researchers from the University of Basle, Switzerland, have also found high blood mercury levels, more than double those of the control groups, in AD patients, with early-onset AD patients having the highest mercury levels of all.42 Trace amounts of mercury can cause the type of damage to nerves that is characteristic of AD, according to recent research at the University of Calgary Faculty of Medicine, strongly suggesting that the small amounts we are exposed to, for example, from amalgam fillings, may be contributing to memory loss.43 Although the research on the link of mercury to AD is in its infancy, it is certainly logical to reduce exposure to this highly toxic metal.
Detoxifying your body
You can easily test your own mineral levels with a hair mineral analysis (see Resources). But what do you do if you have raised levels of toxic minerals?
Once we’ve ingested toxic minerals, they must compete with other minerals for absorption. These minerals are called antagonists and form our first line of defense. Once a mineral has been absorbed, some natural body substances latch on to it and try to take it out of the body. These are called chelators (pronounced key-lay-tors).
It is the latter principle that lies behind the administration of two drugs, penicillamine and EDTA, given to get rid of heavy metals. However, vitamin C is even better. In a study of rats with high concentrations of lead in their brains, administering EDTA resulted in an 8 percent lowering of lead, while vitamin C decreased levels by 22 percent.44 Vitamin C is a virtuoso with the ability to latch on to most heavy metals in the blood and escort them out, sacrificing itself in the process. So high metal burdens call for more vitamin C. It is effective in removing lead, arsenic, and cadmium and is a most important part of any detoxification program.
Another substance that is known to lower lead levels is zinc, which acts as an antagonist to lead by preventing its absorption in the gut. Zinc also lowers body and brain levels of cadmium. Indeed, most of us could benefit from extra zinc. In addition, calcium is effective at keeping down lead levels, since lead otherwise stores more easily in our bones.
Keeping calcium levels full to capacity pushes lead out and prevents the rapid rise in toxic minerals that, according to research by Dr. Ellen O’Flaherty at the University of Cincinnati College of Medicine, occurs at a rate of 15 percent following menopause.45 Calcium is particularly effective at keeping down cadmium and aluminum levels. Toxic elements such as lead and uranium accumulate in bone tissue over a lifetime of repeated exposure and are released into the bloodstream as bone tissue breaks down. Bone loss can increase dramatically following menopause, which explains the rise in blood lead levels found in O’Flaherty’s research.
Selenium is specifically a mercury antagonist and normally protects us from the mercury present in most seafood. Supplementing an extra dose is always a good idea if there are signs of excess mercury. It also has a similar protective effect with arsenic and cadmium, although it is not so pronounced.
Foods that fight heavy metals
In terms of specific foods, there are a few that can help keep your brain clean. Sulfur-containing amino acids are found as the proteins in garlic, onions, and eggs. The specific amino acids are called methionine and cystine and protect against mercury, cadmium, and lead toxicity. Alginic acid in seaweed and pectin in apples, carrots, and citrus fruits also help chelate and remove heavy metals, thereby promoting your health. One more reason for an apple a day.
A few simple steps you can take to avoid toxic minerals
Avoid busy roads and smoky atmospheres where possible.
Remove outer leaves of vegetables and thoroughly wash all fresh produce in a vinegar solution (just add a teaspoonful to a bowl of water) to remove pollutants.
Limit your intake of marlin, swordfish, or tuna to no more than twice a month.
Avoid copper or aluminum cookware and don’t wrap food in aluminum foil (or if you do, put a layer of greaseproof paper in between foil and food).
Cut down on alcohol, as this increases lead and cadmium absorption.
Avoid antacids, which can contain aluminum salts.
Check whether your water pipes are made of lead or copper. If they are, don’t use a water softener, as soft water dissolves lead or copper more easily; do not drink or cook with hot tap water; use a water filter or drink distilled or natural water.
Take a good antioxidant supplement.
Eat mineral-rich foods, such as seeds and nuts.
Eat fruit rich in pectin and vitamin C.
Supplement vitamin C every day, as this protects you from toxic minerals, plus a multimineral containing zinc, calcium, and selenium.
15
Antioxidants—The Power of Prevention
Since the 1980s, more and more research has confirmed that many of the twentieth century’s most common diseases are associated with a shortage of antioxidant nutrients and helped by their supplementation. So important is the role of antioxidants that medical science is beginning to consider the presence of any one of the diseases listed below as a sign of probable antioxidant deficiency, in the same way that scurvy is a sign of vitamin C deficiency.
In the future, we may be tested for blood levels of antioxidant nutrients alongside levels of blood sugar and cholesterol and blood pressure. Capable of predicting your biological age and expected life span, your antioxidant-nutrient status may prove to be your most vital statistic.
PROBAB
LE ANTIOXIDANT-DEFICIENCY DISEASES
Alzheimer’s disease Macular (eye lens) degeneration
Cancer Measles
Cardiovascular disease Mental illness
Cataracts Periodontal (tooth) disease
Diabetes Respiratory tract infections
Hypertension Rheumatoid arthritis
Infertility
The common denominator in the process of aging and its associated diseases is called oxidative damage. This has put the spotlight on the use of antioxidants—nutrients that help protect the body from this damage by preventing and treating disease. So far, over a hundred antioxidant nutrients have been discovered and hundreds, if not thousands, of research papers have extolled their benefits. The main players are vitamins A, C, and E, plus beta-carotene, the precursor of vitamin A that is found in fruit and vegetables. Their presence in your diet and levels in your blood may prove to be the best marker yet of your power to delay death and prevent disease.
What is an antioxidant?
Oxygen is the basis of all plant and animal life. It is our most important nutrient, needed by every cell every second of every day. Without it we cannot release the energy in food that drives all body processes. But oxygen is chemically reactive and highly dangerous: in normal biochemical reactions oxygen can become unstable and capable of “oxidizing” neighboring molecules. This can lead to cellular damage that triggers cancer, inflammation, arterial damage, and aging. Known as free oxidizing radicals, this bodily equivalent of nuclear waste must be disarmed to remove the danger. Free radicals are made in all combustion processes including smoking, the burning of gasoline to create exhaust fumes, radiation, frying or barbecuing food, and normal body processes. Chemicals capable of disarming free radicals are called antioxidants. Some are known essential nutrients, like vitamin A and beta-carotene, and vitamins C and E. Others, like bioflavonoids, anthocyanidins, pyenogenol, and over a hundred other recently identified protectors found in common foods, are not.
The balance between your intake of antioxidants and your exposure to free radicals may be the balance between life and death. You can tip the scales in your favor by making simple changes to your diet and by antioxidant supplementation.
Antioxidants in health and disease
Slowing down the aging process is no longer a mystery. The best results in research studies have consistently been achieved by giving animals low-calorie diets high in antioxidant nutrients—in other words, exactly what they need and no more. This reduces “oxidative stress” and ensures maximum antioxidant protection. Animals fed in this way not only live up to 40 percent longer, but also are more active during their lives. Although long-term studies have yet to be completed, there is every reason to assume that the same principles apply to humans. Already, large-scale surveys show that the risk of death is substantially reduced in those with either high levels of antioxidants in their blood or high dietary intakes.
Burnt foods harm the body. Free radicals, or oxidants, from anything burnt, damage the body resulting in ageing and disease and are disarmed by antioxidant nutrients. In this diagram, GP stands for the antioxidant enzyme glutathione peroxidase, and SOD is the antioxidant enzyme superoxide dismutase.
Conversely, a lower level of vitamin A, vitamin C, and vitamin E is associated with Alzheimer’s disease. The blood levels of vitamin E and beta-carotene in sufferers are half those of elderly people who do not have Alzheimer’s.46 A U.S. study gave 633 disease-free sixty-five-year-olds large amounts of either vitamin E or vitamin C. A small number in each group would have been expected to show the signs of AD five years later. None did.47 Another study, published in the Journal of the American Medical Association, found that the risk of developing AD was 67 percent lower in those with a high dietary intake of vitamin E than in those with a low intake.48
Elderly people with low levels of vitamin C in their blood have eleven times the risk of developing cataracts compared with those with high levels.49 Similarly, those with low vitamin E blood levels have almost double the risk, while people consuming 450 IU of vitamin E a day have half the risk of developing cataracts.50 51
Levels of vitamin A are consistently found to be low in people with lung cancer. In fact, having a low vitamin A level doubles the risk of lung cancer. Similarly, a high intake of beta-carotene from raw fruit and vegetables reduces the risk of lung cancer in nonsmoking men and women.52 In one study, giving a 8,300 IU per day supplement of beta-carotene resulted in 71 percent of patients with oral precancer (leukoplakia) improving, while 57 percent of patients given 200,000 IU of vitamin A per day had complete remission.53 Beta-carotene on its own, however, may not be wise to supplement if you are a smoker (see this page).
Supplementing vitamins E and C effectively halves the risk of ever having a heart attack, while in a massive study on nurses, those who consumed 15 to 5,500 IU of beta-carotene per day had a 40 percent lower risk of a stroke and a 22 percent lower risk of a heart attack compared with those consuming only 1,600 IU per day.54 Those with high dietary intakes of beta-carotene had half the risk of death from cardiovascular disease. Supplementing 1,000 mg of vitamin C also reduces blood pressure.55
Antioxidants also help boost your immune system and increase your resistance to infection. In children, regular supplementation of vitamin A significantly reduces respiratory tract infections. Antioxidants have been shown to reduce the symptoms of AIDS and, in a small number of cases, to reverse the condition. They increase fertility, reduce inflammation in arthritis, and have key roles to play in many conditions, including colds and chronic fatigue syndrome. (For more information on specific diseases see part 7.)
The synergy of antioxidants is vital
As we saw in the chart on this page, antioxidants are team players. You need a combination of vitamins E and C and beta-carotene, as well as glutathione, anthocyanidins, lipoic acid, and coenzyme Q10, to do the job of disarming oxidants properly Taking only one of these antioxidants not only is unwise, but also could be dangerous. While more than two hundred studies have shown that beta-carotene reduces your risk for a variety of cancers, three studies have shown that supplementing beta-carotene on its own can raise the risk of cancer, although only if you smoke. Why the apparent contradiction?
Let’s examine the most recent negative trial, conducted by the National Cancer Institute. They divided people with a history of colorectal tumors into four groups. One group was given 6,900 IU of beta-carotene, a second group was given 100 mg of vitamin C and 600 IU of vitamin E, a third group received the beta-carotene and vitamins C and E, and the fourth group received a placebo. While there was less recurrence of colorectal tumors in the first three groups, there was a modest increase in cancer recurrence among those who took only beta-carotene supplements and both smoked and drank alcohol every day.
Does this mean that beta-carotene is a moralistic vitamin, adding risk to those who both smoke and drink, but saving those who don’t? Of course not. What is almost certainly happening here is that the oxidants in cigarettes are oxidizing beta-carotene and, in the absence of other synergistic vitamins such as vitamin C and E, this does more harm than good. My advice is to quit the cigarettes, eat foods high in antioxidants including beta-carotene, and supplement either a multivitamin containing antioxidants or a good, all-round antioxidant formula. I take both.
Testing your antioxidant potential
Your ability to stay free of these diseases depends on the balance between your intake of harmful free radicals and your intake of protective antioxidants. As the scales start to tip away from health, early warning signs start to develop, such as frequent infections, difficulty shaking an infection, easy bruising, slow healing, thinner skin, or excessive wrinkles for your age.
Another sign of impaired antioxidant status is a reduced ability to detoxify the body after an onslaught of free radicals. So, for example, if you feel groggy or achy after a burst of exercise or after exposure to pollution (such as being stuck in a traffic jam or a room full of cigarette smok
e), your antioxidant potential may need a boost.
A more accurate way to determine your antioxidant status is to have a biochemical antioxidant profile done. This blood test measures the levels of beta-carotene and vitamins C and E in your blood and determines how well your antioxidant enzyme systems (such as glutathione peroxidase) are functioning. Most nutritional laboratories offer this kind of test. A less expensive and less extensive total reactive antioxidant potential (TRAP) test is also available. But while this will indicate if there is an antioxidant problem, it will not define which nutrients are missing. Ask your doctor or nutritionist about these tests, as they are rarely available directly to the public.
Antioxidants—the best foods
Every year more and more antioxidants are found in nature, including substances in berries, grapes, tomatoes, mustard, and broccoli, and in herbs such as turmeric and ginkgo biloba. These substances, such as bioflavonoids, lycopene, and anthocyanidins, are not essential nutrients but are highly beneficial. They are classified as phytochemicals and are discussed fully in chapter 17.
Your Personal Antioxidant Profile
Test your powers of prevention and score one point for each yes answer.
SYMPTOM ANALYSIS
Do you frequently suffer from infections (coughs, colds)? yes / no
Do you find it hard to shake an infection? yes / no
Do you have a recurrent infection (cystitis, thrush, earache, etc.)? yes / no