As the remarkable properties of vitamins have revealed themselves to investigators, so too have those of the various minerals in our food and water. The seven macrominerals-- calcium, chloride, magnesium, phosphorus, potassium, sodium and sulphur--now share the research spotlight with a longer list of essential trace minerals. These are needed only in minute amounts, but their absence results in many disease conditions. The number of trace minerals known to be essential to life now exceeds thirty, and some researchers believe that for optimum health we need to take in every substance found in the earth's crust. Along with familiar trace minerals, such as iron and iodine, the body also needs others less well known, like cobalt, germanium and boron.
Mankind ingests minerals in a number of different forms. He can take them in as salts; that is, as molecules in which a negatively charged atom is bonded ionically to a positively charged atom as in common table salt (sodium chloride) or less well-known salts such as magnesium chloride, calcium phosphate or zinc sulfate. In water and other liquids, these form a solution as the salts dissolve into positively and negatively charged mineral ions.
Minerals are also ingested as integral parts of the foods we eat, in which case the minerals are held ionically in a claw-like way or "chelated" by a large molecule. Examples include chlorophyll (which chelates a magnesium atom), hemoglobin (which chelates an iron atom) and enzymes that chelate copper, iron, zinc and manganese.
Minerals are usually absorbed in ionic form. If they are not in ionic form when consumed, they are ionized in the gut, with salts dissolving into their two components or chelates releasing their key elements. The system by which mineral ions are then absorbed is truly remarkable. If, for example, the body needs calcium, the parathyroid gland will send a signal to the intestinal wall to form a calcium-binding protein. That calcium-binding protein will then pick up a free calcium ion, transport it through the intestinal mucosa and release it into the blood.1 Manganese and magnesium have similar carriers and their absorption, retention and excretion is likewise governed by complex feedback mechanisms involving other nutrients and hormonal signals. Absorption and excretion of phosphorus is regulated in part by activity of the adrenal glands and vitamin D status.
There are a number of factors that can prevent the uptake of minerals, even when they are available in our food. The glandular system that regulates the messages sent to the intestinal mucosa require plentiful fat-soluble vitamins in the diet to work properly. Likewise, the intestinal mucosa requires fat-soluble vitamins and adequate dietary cholesterol to maintain proper integrity so that it passes only those nutrients the body needs, while at the same time keeping out toxins and large, undigested proteins that can cause allergic reactions. Minerals may "compete" for receptor sites. Excess calcium may impede the absorption of manganese, for example. Lack of hydrochloric acid in the stomach, an over-alkaline environment in the upper intestine or deficiencies in certain enzymes, vitamin C and other nutrients may prevent chelates from releasing their minerals. Finally, strong chelating substances, such as phytic acid in grains, oxalic acid in green leafy vegetables and tannins in tea may bind with ionized minerals in the digestive tract and prevent them from being absorbed.
Several types of mineral supplements are available commercially including chelated minerals, mineral salts, minerals dissolved in water and "colloidal" mineral preparations. A colloid is a dispersion of small particles in another substance. Soap, for example, forms a colloidal dispersion in water; milk is a dispersion of colloidal fats and proteins in water, along with dissolved lactose and minerals. Colloidal mineral preparations presumably differ from true solutions in that the size of the dispersed particles is ten to one thousand times larger than ions dissolved in a liquid. Colloidal dispersions tend to be cloudy; or they will scatter light that passes through them. Shine a flashlight through water containing soap or a few drops of milk and its path can be clearly seen, even if the water seems clear.
There is no evidence that the body absorbs colloidal mineral preparations any better than true solutions of mineral salts or minerals in chelated form. Many so-called "colloidal" formulas often contain undesirable additives, including citric acid , that prevent the mineral particles from settling to the bottom of the container. Furthermore, these products may contain an abundance of minerals that can be toxic in large amounts, such as silver and aluminum. Even mineral preparations in which the minerals are in true solution may contain minerals in amounts that may be toxic. If a product tastes very bitter, it probably should be avoided.
Some commercial interests sell minerals chelated to amino acids which they claim do not break down in the gut, but which pass in their entirety through the mucosa and into the blood, thus bypassing certain blocks to mineral absorption. However, such products, if they work, bypass the body's exquisitely designed system for taking in just what it needs and may cause serious imbalances. Obviously, such formulations should be taken only under the supervision of an experienced health care practitioner.
The proper way to take in minerals is through mineral-rich water; through nutrient-dense foods and beverages; through mineral-rich bone broths in which all of the macrominerals--sodium, chloride, calcium, magnesium, phosphorus, potassium and sulphur--are available in ready-to-use ionized form as a true electrolyte solution; through the use of unrefined Sea Salt ; and by adding small amounts of fine clay or mud as a supplement to water or food, a practice found in many traditional societies throughout the world. Analysis of clays from Africa, Sardinia and California reveals that clay can provide a variety of macro- and trace minerals including calcium, phosphorus, magnesium, iron and zinc.2 Clay also contains aluminum, but silicon, present in large amounts in all clays, prevents absorption of this toxic metal and actually helps the body eliminate aluminum that is bound in the tissues.3
When mixed with water, clay forms a temporary colloidal system in which fine particles are dispersed throughout the water. Eventually the particles settle to the bottom of the container, but a variety of mineral ions will remain in the water. These mineral ions are available for absorption, while other minerals that form an integral part of the clay particles may, in some circumstances, be available for absorption through ionic exchange at the point of contact with the intestinal villi.
Clay particles, defined as having a size less than 1-2 microns, have a very large surface area relative to their size. They carry a negative electric charge and can attract positively charged pathogenic organisms along with their toxins and carry them out of the body,4 Thus, clay compounds not only provide minerals but also can be used as detoxifying agents. As such, they facilitate assimilation and can help prevent intestinal complaints, such as food poisoning and diarrhea. They also will bind with antinutrients found in plant foods, such as bitter tannins, and prevent their absorption.
The seven macrominerals, needed in relatively large amounts, are as follows:
Calcium: Not only vital for strong bones and teeth, calcium is also needed for the heart and nervous system and for muscle growth and contraction. Good calcium status prevents acid-alkaline imbalances in the blood. The best sources of usable calcium are dairy products and bone broth. In cultures where dairy products are not used, bone broth is essential. Calcium in meats, vegetables and grains is difficult to absorb. Both iron and zinc can inhibit calcium absorption as can excess phosphorus and magnesium. Phytic acid in the bran of grains that have not been soaked, fermented, sprouted or naturally leavened will bind with calcium and other minerals in the intestinal tract, making these minerals less available. Sufficient vitamin D is needed for calcium absorption as is a proper potassium/calcium ratio in the blood. Sugar consumption and stress both pull calcium from the bones.
Chloride: Chloride is widely distributed in the body in ionic form, in balance with sodium or potassium. It helps regulate the correct acid-alkaline balance in the blood and the passage of fluids across cell membranes. It is needed for the production of hydrochloric acid and hence for protein digestion. It also activates the production of amylase enzymes needed for carbohydrate digestion. Chloride is also essential to proper growth and functioning of the brain. The most important source of chloride is salt, as only traces are found in most other foods. Lacto-fermented beverages and bone broths both provide easily assimilated chloride. Other sources include Celery and coconut.
Magnesium: This mineral is essential for enzyme activity, calcium and potassium uptake, nerve transmission, bone formation and metabolism of carbohydrates and minerals. It is magnesium, not calcium, that helps form hard tooth enamel, resistant to decay. Like calcium and chloride, magnesium also plays a role in regulating the acid-alkaline balance in the body. High magnesium levels in drinking water have been linked to resistance to heart disease. Although it is found in many foods, including dairy products, nuts, vegetables, fish, meat and seafood, deficiencies are common in America due to soil depletion, poor absorption and lack of minerals in drinking water. A diet high in carbohydrates, oxalic acid in foods like raw spinach and phytic acid found in whole grains can cause deficiencies. An excellent source of usable magnesium is beef, chicken or fish broth. High amounts of zinc and vitamin D increase magnesium requirements. Magnesium deficiency can result in coronary heart disease, chronic weight loss, obesity, fatigue, epilepsy and impaired brain function. Chocolate cravings are a sign of magnesium deficiency.
Phosphorus: The second most abundant mineral in the body, phosphorus is needed for bone growth, kidney function and cell growth. It also plays a role in maintaining the body's acid-alkaline balance. Phosphorus is found in many foods, but in order to be properly utilized, it must be in proper balance with magnesium and calcium in the blood. Excessive levels of phosphorus in the blood, often due to the consumption of soft drinks containing phosphoric acid, can lead to calcium loss and to cravings for Sugar and alcohol; too little phosphorus inhibits calcium absorption and can lead to osteoporosis. Best sources are animal products, whole grains, legumes and nuts.
Potassium: Potassium and sodium work together--inner cell fluids are high in potassium while fluids outside the cell are high in sodium. Thus, potassium is important for many chemical reactions within the cells. Potassium is helpful in treating high blood pressure. It is found in a wide variety of nuts, grains and vegetables. Excessive use of salt along with inadequate intake of fruits and vegetables can result in a potassium deficiency.
Sodium: As all body fluids contain sodium, it can be said that sodium is essential to life. It is needed for many biochemical processes including water balance regulation, fluid distribution on either side of the cell walls, muscle contraction and expansion, nerve stimulation and acid-alkaline balance. Sodium is very important to the proper function of the adrenal glands. However, excessive sodium may result in high blood pressure, potassium deficiency, and liver, kidney and heart disease; symptoms of deficiency include confusion, low blood sugar, weakness, lethargy and heart palpitations. Meat broths and zucchini are excellent sources.
Sulphur: Part of the chemical structure of several amino acids, sulphur aids in many biochemical processes. It helps protect the body from infection, blocks the harmful effects of radiation and pollution and slows down the aging process. Sulphur-containing proteins are the building blocks of cell membranes, and sulphur is a major component of the gel-like connective tissue in cartilage and skin. Sulphur is found in cruciferous vegetables, eggs, milk and animal products.
Although needed in only minute amounts, trace minerals are essential for many biochemical processes. Often it is a single atom of a trace mineral, incorporated into a complex protein, that gives the compound its specific characteristic--iron as a part of the hemoglobin molecule, for example, or a trace mineral as the distinguishing component of a specific enzyme. The following list is not meant to be exhaustive but merely indicative of the complexity of bodily processes and their dependence on well-mineralized soil and food.
Boron: Needed for healthy bones, boron is found in fruits, especially apples, leafy green vegetables, nuts and grains.
Chromium: Essential for glucose metabolism, chromium is needed for blood Sugar regulation as well as for the synthesis of cholesterol, fats and protein. Most Americans are deficient in chromium because they eat so many refined carbohydrates. Best sources are animal products, molasses, nuts, whole wheat, eggs and vegetables.
Cobalt: This mineral works with copper to promote assimilation of iron. A cobalt atom resides in the center of the vitamin B12 molecule. As the best sources are animal products, cobalt deficiency occurs most frequently in vegetarians.
Copper: Needed for the formation of bone, hemoglobin and red blood cells, copper also promotes healthy nerves, a healthy immune system and collagen formation. Copper works in balance with zinc and vitamin C. Along with manganese, magnesium and iodine, copper plays an important role in memory and brain function. Nuts, molasses and oats contain copper but liver is the best and most easily assimilated source. Copper deficiency is widespread in America. Animal experiments indicate that copper deficiency combined with high fructose consumption has particularly deleterious effects on infants and growing children.
Germanium: A newcomer to the list of trace minerals, germanium is now considered to be essential to optimum health. Germanium-rich foods help combat Rheumatoid Arthritis , food allergies , fungal overgrowth, viral infections and cancer. Certain foods will concentrate germanium if it is found in the soil--garlic, ginseng, mushrooms, onions and the herbs aloe vera, comfrey and suma.
Iodine: Although needed in only minute amounts, Iodine is essential for numerous biochemical processes, such as fat metabolism, thyroid function and the production of sex hormones. Muscle cramps are a sign of deficiency as are cold hands and feet, proneness to weight gain, poor memory, constipation, Depression and headaches. It seems to be essential for mental development. Iodine deficiency has been linked to mental retardation, coronary heart disease, susceptibility to polio and Breast Cancer . Sources include most sea foods, unrefined Sea Salt , kelp and other sea weeds, fish broth, butter, pineapple, artichokes, asparagus and dark green vegetables. Certain vegetables, such as cabbage and spinach, can block Iodine absorption when eaten raw or unfermented. Requirements for iodine vary widely. In general, those whose ancestors come from seacoast areas require more iodine than those whose ancestors come from inland regions. Proper iodine utilization requires sufficient levels of vitamin A, supplied by animal fats. In excess, iodine can be toxic. Consumption of high amounts of inorganic iodine (as in iodized salt or iodine-fortified bread) as well as of organic iodine (as in kelp) can cause thyroid problems similar to those of iodine deficiency, including goiter.5
Iron: As part of the hemoglobin molecule, iron is vital for healthy blood; iron also forms an essential part of many enzymes. Iron deficiency is associated with poor mental development and problems with the immune system. It is found in eggs, fish, liver, meat and green leafy vegetables. Iron from animal protein is more readily absorbed than iron from vegetable foods. The addition of fat-soluble vitamins found in butter and cod liver oil to the diet often results in an improvement in iron status. Recently, researchers have warned against inorganic iron used to supplement white flour. In this form, iron cannot be utilized by the body and its buildup in the blood and tissues is essentially a buildup of toxins. Elevated amounts of inorganic iron have been linked to heart disease and cancer.
Manganese: Needed for healthy nerves, a healthy immune system and blood sugar regulation, manganese also plays a part in the formation of mother's milk and in the growth of healthy bones. Deficiency may lead to trembling hands, seizures and lack of coordination. Excessive milk consumption may cause manganese deficiency as calcium can interfere with manganese absorption. Phosphorus antagonizes manganese as well. Best sources are nuts (especially pecans), seeds, whole grains and butterfat.
Molybdenum: This mineral is needed in small amounts for nitrogen metabolism, iron absorption, fat oxidation and normal cell function. Best sources are lentils, liver, grains, legumes and dark green leafy vegetables.
Selenium: A vital antioxidant, selenium acts with vitamin E to protect the immune system and maintain healthy heart function. It is needed for pancreatic function and tissue elasticity and has been shown to protect against radiation and toxic minerals. High levels of heart disease are associated with selenium-deficient soil in Finland and a tendency to fibrotic heart lesions is associated with selenium deficiency in parts of China. Best sources are butter, Brazil nuts, seafood and grains grown in selenium-rich soil.
Silicon: This much neglected element is needed for strong yet flexible bones and healthy cartilage, connective tissue, skin, hair and nails. In the blood vessels, the presence of adequate silicon helps prevent atherosclerosis. Silicon also protects against toxic aluminum. Good sources are grains with shiny surfaces, such as millet, corn and flax, the stems of green vegetables and homemade bone broths in which chicken feet or calves' feet have been included.
Vanadium: Needed for cellular metabolism and the formation of bones and teeth, vanadium also plays a role in growth and reproduction and helps control cholesterol levels in the blood. Deficiency has been linked to cardiovascular and kidney disease. Buckwheat, unrefined vegetable oils, grains and olives are the best sources. Vanadium is difficult to absorb.
Zinc: Called the intelligence mineral, zinc is required for mental development, for healthy reproductive organs (particularly the prostate gland), for protein synthesis and collagen formation. Zinc is also involved in the blood sugar control mechanism and thus protects against diabetes. Zinc is needed to maintain proper levels of vitamin E in the blood. Inability to taste or smell and loss of appetite are signs of zinc deficiency. High levels of phytic acid in cereal grains and legumes block zinc absorption. Zinc deficiency during pregnancy can cause birth defects. As oral contraceptives diminish zinc levels, it is important for women to wait at least six months after discontinuing the pill before becoming pregnant. Best sources include red meat, oysters, fish, nuts, seeds and ginger.
Not all minerals are beneficial. Lead, cadmium, mercury, aluminum and arsenic, while possibly needed in minute amounts, are poisons to the body in large quantities. These come from polluted air, water, soil and food; lead finds its way into the water supply through lead pipes. Sources of aluminum include processed soy products, aluminum cookware, refined table salt , deodorants and antacids. Baking powder can be another source of aluminum and should be avoided. Amalgam fillings are the principle source of toxic mercury in the system--linked to Alzheimer's and a number of other disease conditions. Minerals like calcium and magnesium, and the antioxidants--vitamin A, carotenes, vitamin C, vitamin E and selenium--all protect against these toxins and help the body to eliminate them. Adequate silicon protects against aluminum.
Linder, Maria C, ed, Nutritional Biochemistry and Metabolism with Clinical Applications, 2nd ed, 1991, Appleton & Lange, Norwalk, CT, 191-212.
Johns, T, and M Duquette, American Journal of Clinical Nutrition, 1991, 53:448-56.
Jacqmin-Gada, H, et al, Epidemiology, 1996, 7(3):281-85; Bellia, J P, et al, Annals of Clinical Laboratory Science, 1996, 26(3):227-33.
Damrau, F, Medical Annals of the District of Columbia, Jun 1961, 30:(6):326-328.
Ensminger, A H, et al, The Concise Encyclopedia of Foods & Nutrition, 1995, CRC Press, Boca Raton, FL, 586.