The New Optimum Nutrition Bible

by Patrick Holford

  Too much iron may also increase the risk of cardiovascular disease. According to a Finnish study of 1,900 men, those with higher iron stores were more than twice as likely to have a heart attack as those with lower iron stores. Jerome Sullivan, a pathologist at the Veterans’ Affairs Medical Center in South Carolina, found a correlation between blood ferritin levels (most iron reserves in the body are stored as ferritin) and cardiovascular risk and thinks that this might explain why menstruating women, who lose iron each month, have a lesser risk of cardiovascular disease than men up until menopause.29 This theory is yet to be proven, but it suggests that meat-eating men should not go overboard on iron supplements. In practice, this means limiting the dose to 10 mg a day unless you are deficient.

  Zinc—a major role player

  A large part of the population is at risk of being zinc-deficient. With half the population eating less than half the recommended daily allowance (RDA), few people get enough from their diet. Deficiency symptoms are white marks on the nails, lack of appetite or lack of appetite control, pallor, infertility, lack of resistance to infection, poor growth (including hair growth), poor skin including acne, dermatitis, and stretch marks, plus mental and emotional problems.

  Zinc deficiency plays a role in nearly every major disease, including diabetes and cancer. Zinc is needed to make insulin, to boost the immune system, and to make the antioxidant enzyme SOD (superoxide dismutase). It is also required to make prostaglandins from essential fatty acids. These hormonelike substances help balance hormones and control inflammation and the stickiness of the blood. Sucking zinc lozenges helps shorten the life of a cold.

  Zinc’s main role is the protection and repair of DNA, and for this reason it is found in higher levels in animals and fish than in plants—animals have higher levels of DNA. A vegetarian diet may therefore be low in zinc. Stress, smoking, and alcohol deplete zinc, as does frequent sex, at least for men, since semen contains very high concentrations of zinc. Oysters are popularly said to be aphrodisiacs. They are also the highest dietary source of zinc, providing about 15 mg per oyster, and for both men and women zinc is essential for fertility.

  How much iron is absorbed?

  Manganese—the forgotten mineral

  This mineral is known to be involved in no fewer than twenty enzyme systems in the body. One of the most critical is SOD, which acts as an antioxidant, helping disarm free radicals. In animals, manganese deficiency results in reduced insulin production. Since diabetics frequently have low manganese levels, it is thought to be involved in maintaining blood sugar balance. It is also involved in the formation of mucopolysaccharides, a constituent of cartilage. One of the first signs associated with deficiency is joint pain.

  Manganese is also required for proper brain function. Deficiency has been associated with schizophrenia, Parkinson’s disease, and epilepsy. It is frequently deficient in the diet and the best sources include tropical fruit, nuts, seeds, and whole grains. Tea is also a significant source of this mineral and can supply half our daily intake. Little more than 5 percent of the manganese eaten in the diet is absorbed, though exactly why is unknown. Similarly, supplements are poorly absorbed, the best forms being manganese citrate or manganese amino acid chelate.

  Copper—good and bad

  Both a nutritional and a toxic element, copper is required by humans in doses as little as 2 mg a day. It is rarely deficient for the simple reason that most water supplies are contaminated by copper pipes. It is needed among other things for the formation of the insulating myelin sheath around nerves. Copper and zinc are strongly antagonistic, and zinc deficiency may lead to a greater uptake of copper. Likewise, excessive zinc supplementation can induce copper deficiency.

  In reality, excess is a more common problem than deficiency. If you are on a whole-food diet, there is no actual need to supplement copper, yet it is often included in multimineral tablets. A good multi should contain roughly ten times more zinc than copper (for example, zinc 10 mg, copper 1 mg). Taking birth control pills or HRT also increases your copper stores. All these factors make it relatively easy to accumulate too much copper, which is associated with schizophrenia, cardiovascular disease, and possibly rheumatoid arthritis. However, copper deficiency has also been associated with rheumatoid arthritis. Copper is a constituent of an antioxidant enzyme involved in some inflammatory reactions. This may be the reason why too much or too little can result in greater inflammation in sufferers from rheumatoid arthritis. Copper levels rise during pregnancy, and it is speculated that it plays a role in bringing on labor and, in excess, postnatal depression.

  Chromium—the energy factor

  This is a vital constituent of glucose tolerance factor, a compound produced in the liver that helps transport glucose from the blood to the cells. vitamin B3 and the amino acids glycine, glutamic acid, and cystine are also required for glucose tolerance factor. Continued stress or frequent sugar consumption therefore deplete the body of chromium. A diet high in refined foods is also likely to be deficient in this mineral since it is found in whole grains, legumes, nuts, seeds, and especially in mushrooms and asparagus. Chromium supplements have been used successfully in the treatment of diabetes and glucose intolerance.

  Selenium—the anticancer mineral

  Deficiency of this mineral was first discovered in China as the cause of Keshan disease, a type of heart disease prevalent in areas in which the soil was deficient in selenium. It has since been associated with another regional disease, this time in Russia, involving joint degeneration. Perhaps the most significant finding is selenium’s association with a low risk of certain kinds of cancer.

  Selenium is the vital constituent of the antioxidant enzyme glutathione peroxidase. A tenfold increase in dietary selenium causes a doubling of the quantity of this enzyme in the body. Since many oxides are cancer-producing, and since cancer cells destroy other cells by releasing oxides, it is likely to be selenium’s role in glutathione peroxidase production that gives it protective properties against cancer and premature aging. It may also be essential for the thyroid gland, which controls the body’s rate of metabolism. Selenium is found predominantly in whole foods, particularly seafood and sesame seeds. If you grind the seeds, the nutrients become more readily available.

  The unknown minerals

  As research unfolds and analytic techniques improve, we will probably find that many more minerals have an important role to play. Some are already proven, although not widely known. They include boron, which helps the body use calcium and may be beneficial for arthritis sufferers; molybdenum, which helps remove undesirable free radicals, petrochemicals, and sulfites from the body and is therefore useful for city dwellers who want protection from pollution; vanadium, proved to be essential in some animals, which may be useful for the treatment of manic depression; and germanium, which has antioxidant potential.

  Since the 1970s, analytical chemists have moved from being able to detect minerals in food, blood, hair, and so on, at a level of one part in a million, to being able to detect one part in a trillion—that’s a millionth of a million, or the equivalent of dissolving a lump of sugar in the Mediterranean and being able to detect the difference. It is highly likely that we have much more to learn about the magic of minerals.

  14

  Toxic Minerals from Aluminum to Mercury

  Since optimum nutrition is about both increasing your intake of nutrients and avoiding antinutrients, it is well worth being aware of the toxic minerals that we are exposed to. These include aluminum, cadmium, copper, lead, and mercury. We are also exposed to some arsenic, present in some pesticides and herbicides, although this is most easily avoided by eating organic foods. There are others, but these are the major toxic minerals of concern because just about everybody is being unwittingly exposed to them.

  Analyses of hair show that these undesirable elements tend to accumulate with age, suggesting that our exposure generally exceeds our ability to get rid of them. However, with some simple strategies you ca
n dramatically reduce your load and increase your body’s ability to detoxify any residues in your body.

  Here’s how.

  Aluminum

  Aluminum is in widespread use in food packaging and turns up in many common household products. It’s in antacids, toothpaste tubes, deodorants, aluminum foil, pots and pans, and water. Not all aluminum will enter the body. Only in certain circumstances will aluminum leach, for example, from a pan. Old-fashioned aluminum cookware, if used to heat something acidic like tea, tomatoes, or rhubarb, will leach particles of aluminum into the water. Also, the more zinc-deficient you are the more you absorb.

  Like many toxic metals, aluminum binds to essential vitamins and minerals, thus seriously compromising nutritional status. Although we know it interferes with brain function and memory, aluminum has also has been linked to kidney problems in babies and behavioral problems and autism in older children.30

  In areas where there are high levels of aluminum in the water, studies have shown that there is a 50 percent greater risk of developing Alzheimer’s disease (AD).30 While plenty of studies have shown increased accumulation of aluminum in people with AD, what isn’t clear is whether this is a cause or a consequence of the disease. The likelihood is that it’s a bit of both and still a significant contributor to memory problems. Numerous epidemiological surveys have linked aluminum intake from water to increased risk of AD. Other sources (food, medicines, toiletries, and cosmetics) are less well investigated.

  In a study in the 1980s of 647 Canadian gold miners who had routinely inhaled aluminum since the 1940s (this used to be a common practice, thought to prevent silica poisoning), all tested in the “impaired” range for cognitive function, suggesting a clear link between aluminum and memory loss.31 A number of recent review papers have kept aluminum firmly on the map of potential contributors to dementia and AD.32 While the mechanism for action of aluminum in brain degeneration is far from clear, aluminum acts as an oxidant in the brain, especially in combination with excess copper.33

  Cadmium

  Cadmium accumulates in the body and brain when zinc is low and builds up in the kidneys and liver, where it binds to other essential minerals and vitamins, thus preventing their utilization. In their study on mineral status in new babies, Professor Derek Bryce-Smith and Dr. Neil Ward, then at Reading University (England), found that cadmium levels are higher in the placentas of stillborn babies or those born with spina bifida. Greater accumulation of cadmium is also associated with low birth weight and small head circumference (therefore reduced brain size); and it reduces fertility in both men and women.

  Our main sources of cadmium are cigarette smoke (directly or passively inhaled—according to the British Health Education Authority, only 15 percent of the smoke from a cigarette is inhaled by the smoker; the rest goes into the air and is inhaled by those close by) and refined grains found in processed foods. Cadmium is also widely used by the manufacturing industries and has even been found in shellfish from polluted waters.

  Copper

  Copper is both an essential element and a toxic one. Owing to the widespread use of copper in water pipes, plus exposure from jewelry, kitchen utensils, and even swimming pool antifungal agents, we are today more at risk from toxicity than from deficiency. The 2 mg we need each day is supplied simply from drinking water that has passed through copper pipes, irrespective of any copper that is absorbed from our food. What’s more, long-term use of contraceptive pills, IUDs, and fertility hormones such as Clomid further increases copper levels in the body. Yet high levels of copper antagonize zinc and can induce deficiency.

  Once a woman is pregnant, copper levels in her blood tend to rise dramatically and remain elevated until about a month after her child’s birth. The reason is believed to be because copper acts as a stimulus for the uterus. But if there’s already a high level to start with, the additional accumulation can cause copper toxicity, and this is far more common during pregnancy than at other times. In fact, too much too soon may be a factor in inducing premature babies or miscarriages.

  High levels of copper may also be a factor in postpartum depression or mental illness, especially anxiety, paranoia, and schizophrenia. Consider this story. On vacation, I once met a headmaster of a school for “problem” children. We got talking about the effects of lead and other toxic metals on behavior and decided to set up a challenge. When we returned from vacation, he would send me a dozen hair samples from different students, which I would analyze and use to predict their behavior.

  After receiving the hair samples, I ran the hair mineral analyses and found three abnormal results. One had a very high lead level. I predicted aggressive behavior, hyperactivity, and poor attention span. I was right. The child in question was the worst-behaved in the school! Two others had high copper levels. I predicted anxiety. They turned out to be a schoolteacher and his wife. They had recently moved into a new house, built in the grounds of the school, with new copper pipes in a soft-water area. The wife had started to become more and more anxious and had been prescribed medication. The husband was apparently free of symptoms.

  This story illustrates how easy it is to be copper toxic without knowing it. Copper excess, which can cause extreme fears, paranoia, and hallucinations, is rarely checked or tested in those with mental health problems, despite the fact that this link has been often reported in people with schizophrenia.34 The copper may be the result of drinking water passing through copper pipes, or using copper pots and pans, birth control pills, and even copper IUDs. Or it could be the result of a deficiency of zinc, or of vitamin C or B3, which are copper antagonists. It also highlights the importance of drinking filtered or bottled water.

  Lead

  The first study to shake the status quo on lead toxicity was the Needleman study. Herbert Needleman, an associate professor of child psychiatry, looked at a group of 2,146 children in first- and second-grade schools in Birmingham, Alabama. He examined lead concentrations in shed baby teeth to obtain more long-term levels than shown by a simple blood test. He then asked the schoolteachers to rate the behavior of children they had taught for at least two months. This was done using a questionnaire designed to measure the teachers’ rating of children for a number of characteristics. He also ran a series of behavioral, intellectual, and physiological tests on each child before dividing the children into six groups according to the lead concentration in their teeth.

  Classroom behavior in relation to dentine lead concentration: results for 2,146 children. The higher the level of lead in a child’s baby teeth, the worse their behavior and learning ability is likely to be. By comparing 1 and 6 in each category (that is, the lowest and highest levels of lead), you can see a clear difference in behavior.

  As you can see, his results showed a clear relationship between lead concentrations and bad school behavior, as rated by the teachers without any knowledge of the children’s lead levels. Needleman also found that the average IQ for the high-lead children was 4.5 points below that of the low-lead group. Reaction time (a measure of attention capability) was also consistently worse in those with higher lead levels. EEG readings (which measure brainwave patterns) showed clear differences based on lead concentration. Perhaps the most interesting result was that none of the high-lead children had an IQ above 125 points (100 is average), compared with 5 percent in the low-lead group.35

  Richard Lansdown, principal psychologist at the London Hospital for Sick Children, and William Yule, psychologist at the University of London, decided to replicate the essentials of Needleman’s study on London children using lead levels in the blood instead of teeth. The 160 children involved had blood lead levels from 7 to 33 micrograms per decilitre, averaging 13.5 mcg/dl (35 mcg/dl is the “safe” level recommended by the Lawther report Lead and Health, 1980). This is similar to other national studies of mean lead levels. Again, the teachers rated the children’s behavior, and IQ and other tests were made. Lansdown’s results were even more striking than Needleman’s. The difference in IQ s
core between high- and low-lead children was seven IQ points. Once again, none of the high-lead children had an IQ above 125, while in the low-lead group, 5 percent did.36 His findings have long since been proven by many other researchers and in fact helped bring about the banning of lead in gasoline.

  Professor Derek Bryce-Smith has also found elevated levels of lead in the placentas of stillborn babies and those born with spina bifida or “water on the brain” (hydrocephalus).37 An American study also found higher levels of lead in babies who died of crib death.38 Perhaps more interesting is the fact that this correlation exists even in mothers whose lead levels would be considered normal. As with many environmental poisons, there appears to be no threshold at which lead can categorically be called safe.

  The important lesson to learn from lead is that tiny changes in what we ingest can have vast consequences for our health, which, although invisible to the eye, have been proven by research. Banning lead in gasoline was the first campaign of the Institute for Optimum Nutrition, working with Professor Bryce-Smith. There are many others yet to be won.