Chapter 6 – Minerals, Coenzymes & Amino Acids
In this chapter we discuss the different minerals, coenzymes, amino acids and proteins that have been shown to prevent cancer. They are listed in order of importance.
Selenium
Selenium is a non-metallic trace element that human beings obtain from water and food, especially seafood, meats, wheat germ, garlic, onions and nuts (especially Brazil nuts). It is a very strong antioxidant, which, besides cancer prevention, is also known to help prevent heart disease, protect the skin, support male fertility and the prostate, and to boost the antioxidant effects of vitamin E and glutathione (glutathione might be the most important antioxidant in the human body and is involved in enzymes that are critical for the elimination of toxins from our body). Low selenium levels may lead to decreased levels of coenzyme Q10, another important cancer preventer. Population studies in the US and China have shown that people living in areas with low levels of selenium in the soil have a higher probability of developing certain cancers.
Moss describes the results of several studies that demonstrate selenium's strong anti-cancer properties. In the 1960's, Dr. Raymond Shamberger found that people living in states with low selenium levels in the soil had higher rates of heart disease than people in states with high selenium levels. Then in 1976 Dr. Shamberger also found that cancer rates were significantly lower in cities and states with high selenium levels in the soil. A study at the Harvard School of Public Health found that people with the lowest levels of selenium in their blood had twice the likelihood of developing cancer as those with the lowest levels. In China, in a region with low selenium levels in the soil, people were given table salt that had been enriched with selenium. After 8 years, liver cancer incidence fell by 35percent.
Researchers have also found that selenomethionine, a form of selenium, activates the famous, tumor-suppressing p53 gene, which is often inactive in many types of cancer. A study by the Stanford University Medical Center and Johns Hopkins University School of Medicine also found that higher plasma selenium levels are associated with lower prostate cancer risk.
A University of Arizona study on the effect of selenium on skin cancer found that selenium does not directly help prevent skin cancer. However, prostate, esophageal, colorectal and lung cancer rates decreased 71, 67, 62 and 46 percent respectively over the placebo group in the study. The study also showed that people taking selenium supplements (200 mcg daily) over 10 years had an overall 41 percent lower chance of developing cancer and a 52 percent lower cancer mortality rate. Other studies suggest that selenium may also protect certain women from breast cancer.
Barrett's esophagus is a condition in which acid reflux of stomach acids causes damage to cells in the lower esophagus. Barrett's esophagus significantly increases the risk of esophageal cancer. Studies have found that people with Barrett's can reduce their risk of developing esophageal cancer by maintaining high selenium levels.
The results revolving around prostate cancer make sense since most prostate cancer cases involve older men, and people tend to have lower selenium levels as they get older. From the evidence, it appears that selenium is a must supplement for everyone, but especially for older men. It is definitely the most important mineral in cancer prevention.
It can arguably be said that most people probably don't receive the RDA of 55-70 micrograms of selenium from dietary sources. Garlic has been thought to prevent cancer and other diseases for a long time. It just so happens that garlic has a high selenium content, which is probably one of the reasons that it is an important cancer inhibitor.
Alpha-lipoic acid
Alpha-lipoic acid, an enzyme produced in the energy-producing parts of cells, is a very powerful antioxidant. It is believed to enhance the effectiveness of other important antioxidants such as vitamins C and E, CoQ10 and glutathione and to recycle them. It is also involved in the production of the all-important glutathione. Dietary sources include spinach, liver, and brewer's yeast. Besides protecting against cancer, it protects the liver, helps with many complications experienced by diabetics, and helps preserve brain cells after stroke.
The body produces alpha-lipoic acid so that it can convert fat and sugar to energy, but excess amounts are able to circulate freely throughout the body. One of the most interesting properties of alpha-lipoic acid is that it dissolves in both water and fat, whereas most other antioxidants are either fat or water-soluble, but not both. This limits their areas of activity. Water-soluble antioxidants work inside our cells and other "watery" areas of our body, whereas fat-soluble antioxidants work in the fatty areas of cell membranes and other lipids. Hence, alpha-lipoic acid can be displaced throughout the body to the areas where the most oxidative damage is occurring to cells at a particular time, thus making it a strategically important antioxidant.
Most of the studies done on alpha-lipoic acid have been on animals. Its cancer-preventing properties have not been proven in humans, but it is such a special antioxidant that we believe that research will soon show that it is an important cancer preventer. The fact that it is such a strong and versatile antioxidant by itself is enough to recommend it in cancer prevention. Add to this the boost it gives to other cancer-preventing antioxidants and you have something really powerful.
Zinc
Zinc is one of the most important minerals in the body since it is part of hundreds of enzymes and is therefore involved in almost every biological process in the human body. It is especially important in the immune system, and even slight deficiencies in the mineral can lead to weakened immunity. Studies have shown that it even reduces the duration and severity of the common cold. The best dietary sources for zinc include lean meat, fish and other seafood, poultry, eggs, and whole grains.
Since the immune system is what typically keeps us from developing cancer, and zinc is required to maintain a strong immune system, zinc should be an integral part of every cancer prevention program. It has been found that cancer patients quite often have reduced zinc levels, and it is believed that this deficiency is one of the factors that led to their cancer.
Moss describes some studies that demonstrate its cancer prevention properties. A study in a high cancer rate region of China was performed on over 30,000 subjects over a nine year period. The study found that stomach cancer rates dropped by 62 percent for those taking a zinc-vitamin A supplement. Incidence rates for other cancers also decreased significantly, and overall cancer death rates decreased substantially as well. A study in India found that changes to DNA that are caused by smoking decreased by 72 to 95 percent in the subjects taking zinc-vitamin A-riboflavin (a B vitamin) supplement and selenium.
Coenzyme Q10 (CoQ10)
CoQ10 is found in the mitochondria of all our cells and is part of the energy-production system of cells. As an antioxidant, it helps protect against cellular damage by free radicals that are generated when we expend large amounts of energy. In particular, it protects cell membranes from lipid peroxidation. It is also believed to help athletic performance because of its energy-production function.
Studies have found that low CoQ10 levels are associated with cancer and heart disease. An important study that took place between 1993 and 1995 in Copenhagen found that breast cancer tumors were completely eliminated in some patients when they took large doses (390mg) of CoQ10 over several months. It also gives a big boost to the immune system, which is probably another reason that most researchers believe that it helps prevent cancer. Like other antioxidants, it works synergistically with vitamin E, preventing it from being oxidized.
As far as heart disease goes, CoQ10 has been shown to prevent it in the first place and to help people recover after heart surgery. This makes sense since this coenzyme is most abundant in the cells of the heart.
It is a fat-soluble antioxidant with no known toxicity even in high doses. To obtain therapeutic levels of CoQ10, it must be taken as a supplement since there is not enough of it in the few foods that contain it. As it happens with many other important antioxidants, its abundance in our bodies declines with age, so people should take higher doses as they get older.
Glutathione
Glutathione is one of the most important antioxidants in the body because it is found in virtually every human cell, especially in those comprising our immune system. Since this protein is in every cell, in theory it can stop free radicals from damaging DNA at every possible opportunity. Besides acting as an antioxidant, glutathione detoxifies heavy metals and chemicals, and it protects cell membranes. A long-term glutathione deficiency therefore increases cancer risk significantly. It also protects both normal and cancer cells from radiation, so glutathione and its precursors (see below) must not be taken by cancer patients undergoing radiation. It is also another one of those synergistic antioxidants that recycle vitamin C and E or protect them from becoming oxidized.
Our body generates glutathione, which is difficult to obtain from dietary sources. Supplements are not an option for this antioxidant because glutathione is destroyed during digestion and therefore cannot be absorbed. So why do we bring it up if we can't do anything about it? Well, there are other substances that you can take that raise your glutathione levels.
N-acetylcysteine (NAC) is a derivative of the amino acid cysteine. It is broken down during digestion and put back together as glutathione in our body, which is the reason that it is the best way to raise our levels of glutathione. It is also known to help prevent Alzheimer's disease and to reduce plaque build-up in arteries that leads to heart attacks. Women with high blood levels of cysteine have been found to have much lower breast cancer rates than the average woman as well.
Glutamine is one of the most important amino acids for building protein in our bodies. It is also converted to glutathione, making it very important in the cancer prevention process. Tumors need glutamine to grow, which means that they deplete the body's natural glutamine stores. The lack of glutamine probably leads to a lack of glutathione which in turn exacerbates the cancer process once it has started.
Alpha-lipoic acid is also involved in the body's production of glutathione and helps protect it and recycles it.
Whey protein is also partially converted to glutathione. Many protein powder supplements are made of whey protein, and this is probably the best way to obtain this kind of protein. Whey is one of the two primary proteins in milk and is usually sold in powder form.
Arginine
Arginine is a "non-essential" amino acid because it is manufactured by the body. It is believed to increase human growth hormone (HGH) levels in the body, which in turn enhance the body's immune system. Increased HGH levels also increase the number of natural killer (NK) cells and lymphocytes that help prevent and fight cancer. Arginine also reduces inflammation and dialates blood vessels, thus helping blood circulation and reducing the risk of heart disease.
Animal studies have shown that arginine reduces the number and size of tumors and that it increases the production of lymphocytes. It has also been found to prevent heart disease. Although it is manufactured by the body, it is not made in enough quantities for optimal health. Hence, supplementation is advisable. The most common form is L-arginine.
Calcium
Calcium is important for several bodily functions. It is a major component of our bones and teeth, but it also functions in cell-to-cell communications, lowers blood pressure in some individuals, decreases premenstrual symptoms in women, and is involved in muscle contraction, nerve impulse transmission and blood clotting. Several studies have found that calcium helps prevent colon cancer.
A 2004 study at the Dartmouth-Hitchcock Medical Center that included over 900 men and women demonstrated that high doses of supplemental calcium, in addition to the calcium most people obtain from their diet, reduces the risk of advanced polyps in the colon developing into cancer. A 2005 study from the University of Minnesota, which included over 45,000 women and took place over 8.5 years found that women who consumed over 800 mg of calcium per day, from either dietary sources or supplements, reduced their risk of colorectal cancer by over 45 percent. Those who had the highest intake and took calcium supplements had the greatest protection.
Calcium is found in dairy products, fish, shell fish, and broccoli among other foods. It is best absorbed when sufficient vitamin D is available in the body. Since most people cannot obtain enough calcium through their diet (adults require 1,000-1,500 mg per day), supplements of this important mineral are highly recommended. Dairy products have been linked to increased prostate cancer risk in some studies, so men should do their best to find other sources of calcium. This increase is probably due to the fat content of dairy foods or the hormones given to cattle, and not to the calcium they contain.
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