Vitamins, Minerals
& Weight Loss

Below is an excerpt from Part Two of

The 2004 Multi-Diet

by Anderson A. Anonymous, M.D., Ph.D.

Magnesium

Recommended Dietary Intake

400-mg is the Daily Value (DV) for magnesium set by the U.S. Food and Drug Administration. The Food and Nutrition Board set the official scientific US RDA at 4.5-mg magnesium per kg of body weight. The healthy adult human body contains 20,000- to 30,000-mg (20–30 g) of magnesium. The chemical symbol for magnesium is “Mg”.

Usual Magnesium Intakes

The FDA’s Total Diet Study showed normal U.S. intakes of magnesium intakes to be in the 200-mg to 300-mg range. This is probably submarginal for most people. The U.S. Third National Health and Nutrition Examination Survey (NHANES III) also shows that U.S. adults over the age of 16 usually do not get enough magnesium in their normal diets. Marginal magnesium deficiency is therefore considered to be common.

Absorption, Metabolism, Excretion of Magnesium

About 50% of dietary magnesium can typically be absorbed by the small intestine. The kidney can easily excrete any excess that may be absorbed. Together these two organs can maintain tight homeostatic control over very wide dietary intake ranges. Because of this, it is considered extremely unlikely that anyone would get too much magnesium from food alone.

Magnesium Deficiency/Toxicity Symptoms

Known magnesium deficiency symptoms include: weakness, tiredness (lack of energy), dizziness, nervousness, irritability, muscle cramps, tremors, twitching, unsteady walking, irregular heartbeat, loss of hair, mental confusion, disorientation. (Magnesium supplements will reverse these clinical signs within a few days.)

Known magnesium toxicity symptoms include nausea, vomiting, slowed breathing, and coma. However, a toxic condition is difficult to achieve without taking pure magnesium salts.

Food Sources of Magnesium

The protein foods you eat on the Multi-Diet are relatively poor sources of magnesium. Fish, meat, milk, and most commonly eaten fruits have relatively little of it.. Vegetables and unrefined grains are somewhat better. However, in many such foods, the magnesium is in the outer skin or husk. Food processing techniques tend to remove this and thereby reduce the amount of magnesium available. It is not usually added back during enrichment. Diuretics, including alcohol and caffeine, also cause increased magnesium losses.

Supplemental Sources of Magnesium

Fortunately, magnesium supplements are easily available: dolomite, magnesium carbonate, magnesium citrate, magnesium aspartate, magnesium fumarate and magnesium amino acid chelates. (Note: the magnesium from magnesium oxide and magnesium hydroxide is not well absorbed, so these forms are more usually used as laxatives or antacids.) Magnesium tablets are available in supermarkets, drugstores, and health-food stores. The tablets that combine calcium and magnesium are usually the most convenient.

Deductive Advice about Magnesium

Your normal diet may well be marginally deficient in magnesium. A reducing diet will likely make this worse unless you supplement magnesium in some way. Therefore, a supplement of one-half the RDI is probably a minimum supplement. If you somehow get too much, your kidneys can usually remove it, so it probably isn’t dangerous. But don’t routinely overdo, because if your body has to excrete large amounts of magnesium, it may have to use up too much calcium, phosphorus, or other such resources in the process—and this can cause relative deficiencies of these things.