Dietary Minerals Do We Need Them?


While vitamins usually take center stage in any discussion of dietary supplements, minerals too are essential for good health and for growth. Just the right amounts of minerals in our diets are necessary.

Some minerals are needed in relatively large amounts in the diet such as calcium, phosphorus, sodium, chloride, potassium, magnesium, and sulfur. "Large" is measured in a range of milligrams to one gram.

Other minerals called "trace minerals," are needed in small amounts. These are iron, manganese, copper, iodine, zinc, cobalt, flour-ine, selenium, and perhaps others.

Some minerals such as lead, mercury, and cadmium, are regarded as harmful.

Too much can be harmful

Even minerals that the body requires for good health can be harmful if we get too much of them.

For example, if all the potassium the body requires in one day is taken in a single, concentrated dose, severe illness can result. Many children under 5 years of age are hospitalized each year due to iron poisoning caused by accidental ingestion of multiple daily dietary supplements. Some of these children die.

Other minerals can cause adverse health effects if an individual takes as little as twice as much as is required to maintain good health.

Taking too much of one essential mineral may upset the balance and function of other minerals in the body. Excess mineral intake can reduce an individual's ability to perform physical tasks and can contribute to such health problems as anemia, bone demineralization and breakage, neurological disease, and fetal abnormalities.

The risks are greatest for the very young, pregnant or lactating women, the elderly, and those with inadequate diet or chronic disease.

There are a number of things we do not know about the function of minerals in the body, particularly the trace elements. It is clear, however, that people who take mineral supplements should not use them in amounts greatly in excess of what the body requires.

The function of minerals in your body

Mineral elements have two general body functions - building and regulating. Their building functions affect the skeletal and all soft tissues. Their regulating functions include a wide variety of systems, such as heartbeat, blood clotting, maintenance of the internal pressure of body fluids, nerve responses, and transport of oxygen from the lungs to the tissues.

Minerals that are present in relatively large amounts in the body and are required in fairly large amounts in the diet (more than 100 milligrams per day) are generally classified as macrominerals. The others are classified as "trace elements."

MACROMINERALS

CALCIUM is present in the body in greater amounts than any other mineral. Almost all of the 2 or 3 pounds present in the body are concentrated in the bones and teeth.

Small amounts of calcium help to regulate certain body processes such as the normal behavior of nerves, muscle tone and irritability and blood clotting. Although growing children and pregnant and lactating women have the highest calcium needs, all people need calcium in their diets throughout their life.

Milk and milk products are good sources of this mineral.

PHOSPHORUS is present with calcium, in almost equal amounts, in the bones and teeth, and is an important part of every tissue in the body. It is widely distributed in foods, so a sufficient supply is easily obtained in the diet.

Good sources are meat, poultry, fish, eggs, and whole-grain foods.

SODIUM & CHLORIDE are the two elements which combine to form sodium chloride (table salt), but each has separate functions in the body.

Sodium is found mainly in blood plasma and in the fluids outside the body cells, helping to maintain normal water
balance inside and outside the cells.

Chloride is part of hydrochloric acid, which is found in quite high concentration in the gastric juices and is very important in digestion of food in the stomach.

POTASSIUM is found mainly in the fluid inside the individual body cells. With sodium, it helps to regulate body fluid's balance and volume. A potassium deficiency is very uncommon in healthy people but may result from prolonged diarrhea or from diuretics (which cause high urine volume).

Potassium is abundant in almost all foods both plant and animal.

MAGNESIUM is found in all tissues, but principally in the bones. It is an essential part of many enzyme systems responsible for energy conversions in the body. A deficiency of magnesium in healthy humans eating a variety of foods is uncommon, but it has been observed in some post surgical patients, in alcoholics, and in certain other disease conditions.

SULFUR is also present in all body tissues and is essential to life. It is related to protein nutrition because it is a component of several important amino acids. It is a part of two vitamins, thiamine and biotin. The complete function of sulfur has not yet been established.

TRACE ELEMENTS

The essential trace elements are present in extremely small amounts in the body, but, as with the other essential nutrients, we could not live without them. Most of them do not occur in the body in their free form, but are bound to organic compounds on which they depend for transport, storage, and function.

IRON is an important part of compounds necessary for transporting oxygen to the cells and making use of the oxygen when it arrives. It is widely distributed in the body, mostly in the blood, with relatively large amounts in the liver, spleen, and bone marrow.

The only way a significant amount of iron can leave the body is through a loss of blood. This is why people who have periodic blood losses or who are forming more blood have the greatest need for dietary iron.

Women of child-bearing age, pregnant women, and growing children are most likely to suffer from iron-deficiency anemia because of their higher needs.

MANGANESE is needed for normal tendon and bone structure and is part of some enzymes. Manganese is abundant in many foods, especially bran, coffee, tea, nuts, peas, and beans.

COPPER is involved in the storage and release from storage of iron to form hemoglobin for red blood cells. The need for copper is particularly important in the early months of life and, if the intake of the mother is sufficient, infants are born with a store of copper. Copper occurs in most unprocessed foods. Organ meats, shellfish, nuts, and dried legumes are rich sources of this mineral.

IODINE is required in extremely small amounts, but the normal functioning of the thyroid gland depends on an adequate supply. With a deficiency of dietary iodine thyroid enlargement (goiter) occurs.

ZINC is an important part of the enzymes that, among other functions, move carbon dioxide, via red blood cells, from the tissues to the lungs where it can be exhaled.

Zinc is usually associated with the protein foods.

COBALT by itself is not essential in the body, but it is a part of vitamin B-12 which is an essential nutrient.

CHROMIUM acting with insulin, is required for glucose utilization. A deficiency can produce a diabetes-like condition.

SELENIUM appears to have a "sparing action" on vitamin E. A variety of problems occur in selenium and vitamin E deficient animals. Most of these are cured by either selenium or vitamin E. From the important functions that have been shown in animals, it is reasonably certain that selenium is equally important for man.