Do you remember the Periodic Table in your high school chemistry class? It listed all the natural elements and minerals in nature. At present, there are about 109 of these elements that make up all matter. Some are gases such as oxygen and helium. Most are hard substances that you can see and touch. Not many are needed by the body,. Indeed, most will poison us. None of them are complex proteins or even a lowly amino acid. Each is simply a single atom with its own unique orbit of electrons flying around its central core. Except to chemists, physicists and those who tout and sell minerals as a health benefit, they are not very exciting. Gold and silver are the rather nice exceptions.
There are 15 minerals that the body does need in order to function properly. The ones needed in large amounts are calcium, phosphorus and magnesium. The body also needs much smaller amounts of magnesium, aluminum, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, zinc, chloride, potassium and sodium. Let’s look at them.
Adequate calcium is needed for strong bones and teeth and, in tiny amounts, to make many of the body’s cells function properly. Most importantly, especially in females, bones begin to lose calcium with age, especially after menopause so that osteoporosis develops frequently in older women. The danger of osteoporosis, aside from the disfiguring humpback, is that the person, usually a woman, is at increased risk for fracture of the spine and especially, the hip. A fractured hip in an older person is worse than cancer, as almost 50% of these people will be dead within a year. The risk factors for osteoporosis are being of the white or Asian race, having osteoporosis in a parent or sibling, cigarette smoking, excessive alcohol use and physician inactivity. A major factor beginning early in life is inadequate calcium intake. If you drink a quart of any type of milk each day, you get enough calcium, 1500 mg. Dairy products are high in calcium but, like whole milk, most also have lots of fat and calories. Shellfish, almonds, figs, broccoli, calcium-fortified soy and rice milk, kale and collard greens all are good sources of calcium. So, if dairy products and these other foods are not part of you regular daily diet, there is probably inadequate calcium intake.
You also need to remember that vitamin D works with calcium in the diet to increase intestinal absorption of calcium. Sunlight on the skin causes vitamin D to be formed in the body. For white individuals, as little as 15 minutes of sunlight a day on the skin is usually enough. It is probably worthwhile for those who get little sunlight to take a supplement. Dark-skinned and black individuals do not convert sunlight into vitamin D so they need to get vitamin D in their food or supplements. Calcium comes in many forms and dosages. Calcium carbonate is the cheapest and safest. Other forms of calcium such as oyster shell and dolomite often contain toxic substances such as lead – avoid them. 500-600 mg of calcium carbonate twice a day along with vitamin D 800-1200 IU per day is enough. The simplest thing is to drink a quart of vitamin D fortified milk each day. Choose the low-fat type. For those compulsive individuals who want to know the exact recommendation, the following 1997 guidelines have been published by the Institute of Medicine.
|Pregnant or lactating women||All Others|
|under 18 yrs||1300||14-18 yrs||1300|
|18-50 yrs||1000||19-50 yrs||1000|
|Over 50 Yrs||1200|
Phosphorus and Magnesium
You don’t have to worry about these as there is plenty in the regular foods you eat.
Iron is needed for the red blood cells which carry oxygen. It is also necessary in tiny amounts for many cell functions. For years it was felt that iron was necessary for strength and health. Premenopausal women do lose an average of 3 mg a day while men lose 1 mg a day in the stool. So menstruating and pregnant females need more iron. In addition, children from poor families are often deficient in iron as they may not have an adequate diet. A point to remember is that the body can lose only 1 mg of iron a day excreted in stool and, of course, more through the menses. This means that most people really don’t need to take iron. In fact, there is increasing evidence that high iron blood levels may be linked to heart disease. In addition, a common gene for the disease hemochromatosis can cause the build up of huge amounts of iron in the body, eventually seriously damaging the liver, heart and pancreas. If you are healthy and not a menstruating female, you don’t need extra iron, even in the small doses in a multivitamin-mineral preparation. The old adage that iron means good health is an unhealthy old wives’ tale.
Selenium can act as an antioxidant. The body needs very tiny amounts of this mineral, only 50-70 micrograms a day. That is less than one millionth of a gram. If you eat a fairly balanced diet, especially one with adequate grains, you usually get all the selenium you need. Except in certain parts of China, selenium deficiency is virtually unknown. A medical study suggests that selenium supplements decrease cancer risk. However, much more research needs to be done before the medical community accepts this as a fact. Further, if cancer risk is the objective, then by far the best thing to do is not to smoke cigarettes, eat lots of vegetables and fruits, reduce high fatty foods, do aerobic exercise, avoid excessive sunlight and sunburn, and have your colon and breast checked for cancer by proven means. These may not be very exciting ways to reduce cancer risk, but they have been proven by the Scientific Method. By the way, excessive selenium ingestion can make you lose your hair and nails. It is okay if your multivitamin-mineral supplement contains up to 200 micrograms of selenium.
Tiny amounts of chromium are needed to help regulate blood sugar, but it has never been clearly shown that taking extra is helpful in diabetes or heart disease. Chromium reacts with vitamin C and other antioxidants to produce changes in the body’s DNA, its genetic material. A tiny amount in a multivitamin-mineral supplement is no problem but you really get all you need in whole grain foods.
Zinc has been touted as preventing the common cold, Alzheimer’s disease and curing impotence. The medical studies are conflicting and not very impressive. An adequate amount of zinc is important for the normal function of taste and smell and , probably, to maintain the immune system. Vegetarians and the elderly perhaps may not get enough so they may need a supplement. Generally, you only need 12-15 mg a day. Let’s look at the down side. Even if you take a supplement with as little as 50-75 mg of zinc a day, this amount may decrease the good HDL cholesterol in your body. It is proven that this HDL cholesterol does protect you from heart disease, so you don’t want to lower it. You need very little zinc and you usually get all you need in the diet. A small amount in a multivitamin-mineral supplement is not harmful.
As an aside, preventing common colds is easier than treating them. Most colds occur when a person picks up the virus on their fingers (perhaps by shaking hands with someone who has just picked his nose or has a cold). The person then touches the corner of the eye. Humans have a natural tendency to touch their nose and eyes frequently during the day. The virus then flows down the lachrymal duct at the inside corner of each eye. This duct carries excessive tears and, of course, the virus from the eye into the nose. Presto! The virus has found a home and you have the common cold. So wash your hands often, avoid those with colds, and do not touch your nose or eyes. This is better advice than taking zinc.
Potassium is the most common mineral inside the body’s cells. We don’t need to take any supplements. At the same time, eating foods high in potassium such as citrus fruit and juices is a good idea. Medical studies show that high blood pressure may be more effectively treated if the diet is high in potassium. A potassium rich diet may also reduce the risk of stroke. So eat high potassium foods but do not take supplements unless discussed with your physician. See Diets in the Patient Education Section for high potassium foods.
At one time iodine deficiency was common in America leading to thyroid enlargement (goiter) and low thyroid hormone level in the body causing a medical condition called hypothyroidism. Years ago, this problem was corrected by the FDA and food industry by adding iodine to salt and foods. Physicians hardly every see iodine deficiency anymore. A small amount in a multivitamin-mineral capsule is fine.
It is well-proven that fluoride in the drinking water protects the teeth from cavities. Older folks can well remember the regularity with which the dentist had to drill teeth (with no anesthesia) to fill cavities. Now fluoride added in small amounts to municipal water has dramatically reduced the incidence of cavities. A small amount in a multivitamin-mineral supplement is safe.
Sodium & Chloride
Sodium and chloride are the most common minerals in the blood and body fluids but not within cells. The problem with sodium is that so much is available in the foods we eat especially prepared foods of almost every kind. It is a fact that you should use salt and sodium in moderation. In particular, patients with hypertension, fluid retention from any cause, and heart disease should keep their sodium intake at less than 2 grams per day. Do not add sodium or salt to food. Read the food labels. They will tell you how much sodium is in the food you eat. See the Diet Section for detailed information on sodium.
Copper, Manganese, and Molybdenum
Very small amounts of these are needed and you get them from many foods. These may be present in small minimum daily requirements in a multiple vitamin supplement. Do not take more than this as toxicity can occur.