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Trace Elements



Key substances in the body such as vitamins and trace elements NEVER function/work on their own. They always "work/function" closely with OR against a small group of elements or substances, which I call "SISTERS". In addition key substances are also influenced by a larger group of elements or substances which I am calling "COUSINS" and these are all governed by bodily systems which I am calling "AUNTS"


Bound as aluminosilicates and oxides, aluminum is the most abundant metal in the earth's crust. Aluminum is not an essential nutrient for humans. However, goats fed low aluminum diets have been reported to have depressed growth, decreased life expectancy, lack of co-ordination and weakness in their hind legs and an increased number of spontaneous abortions. Chicks on low aluminum diets have depressed growth. In humans the typical daily intake is 2-8mg, much of this is often from food additives. Toxic effects can occur in patients with chronic renal failure, the aluminum coming from the dialysis fluids and/or medications that they receive. Although still controversial, aluminum in the diet does not seem to be a contributing factor in such disorders as Alzeheimer's disease.


They put arsenic in his meat
And stared agast to watch him eat;
- I tell the tale that I heard told,
Mithridates, he died old!
- A.E. Housman (1859-1936)

Arsenic is an essential trace element and too little is toxic, just as, too much is also toxic. It was one of the world's first medicines (in China and Egypt for a start) as well as one of its notorious poisons. However, in Arsenic and Old Lace, the entity was probably strychnine not arsenic.

For many years we have been told that arsenic is a deadly carcinogen. At best (or worst), it is a type of co-carcinogen and only produces tumors under fairly well defined, metabolic circumstances. There are millions of third world people who are at risk from arsenical poisoning, mainly due to the stupidity of officials, whose minds dwell in neatly compartmentalized areas of responsibility and who refuse to look at problems and their possible solution as a whole.

It is nearly exactly a year ago, that I sat opposite an official in another land, who feared for his own life and those near and dear to him, because there had been many deaths in his village due to incorrect installed of tube wells, which had thus spread arsenic pollution even further, rather than solving the problem. He want a magic elixir from me to keep them safe. It was with great reluctance, that he slowly started to answer my questions. How does your family's diet compare with those who are ill? - We eat fairly well, those who are dying were malnourished to begin with. What are the present levels of arsenic and selenium in the water in your village tube wells? - arsenic 2x WHO (World Health Organization) drinking water standard levels, but, selenium we could not measure, it was so low. My guess is that most of the "middle and upper" economic classes, because of their reasonable food intake will be OK healthwise. However, the number of deaths in the rest of the population will continue to mount.

What do I base my crystal ball predictions on? The figures we base our risk assessments on, come from a dirt poor third world community. Their occupations required them to stand in arsenic containing water and mud for many hours a day. Their drinking water stood in uncovered vats, filthy with green slime and red algae and fungi. They ate meat (pork) once per year. They ate fish heads and tails only (the rest of the fish was sold). They had no fruit in their diet and their vegetables were reed type grasses. The bulk of what they ate was a sweet potato type tuber, which was dried for storage, except most of the time it was moldy. Why is this not told in the scientific papers? Yes, it was told right at the beginning by a US naval doctor. However, then 2 things happened, (a) the local national government started sending in free rice and improving the water supply, the reason why this had not been done previously, was because the population at risk, was the local aboriginal peoples, who counted for little in the eyes of the fairly new central government and (b) all descriptions of the diet etc were expunged for good from documents - the diet had "always" included rice, etc, etc, was what it states in all the papers from 1963 on!!!

I have been in many parts of the world, seeking to understand from a practical point of view, when do you see arsenic toxicity and when do you not. The old standard levels of arsenic in drinking water are borderline toxic (that is when you add up the total arsenic content in food plus drinking water per day etc) for a long-term malnourishing, low selenium, low vitamin, low calorie diet. If the person is well nourished, with normal to high levels of selenium, normal vitamin levels and a reasonable caloric intake, the arsenic oral intake may be increased from 2 to 4 fold before chronic toxicity becomes prevalent.

Yes, I am deeply concerned about the levels of arsenic in the drinking water of at least 6 nations, but the U.S. is not one of them!!! I would much prefer public funds to be spent on any of a score of "good" causes, rather than be used in yet another round of "lower the arsenic drinking water standard". This does *not* mean, I don't think industrial arsenic pollution should not be cleaned up. I definitely do! However, I just don't think cleaning up Mother Nature's natural arsenic levels, a worthwhile endeavor.


This is a dietary trace element found mainly in plant foods. It is essential for plant growth and in at least some fish. It may also be essential in humans. In recent research boron has been found to be promoter of bone and joint health and it can influence the cellular transport of calcium. Nutritional forms of boron are readily and nearly completely absorbed. There is no evidence that boron promotes the development of lean muscle mass. However, there are findings that boron can mimic and enhance the effects of estrogen in post-menopausal women and that estrogen replacement therapy used in conjunction with boron may produce synergistic results. Boron appears to be of help in the treatment of osteoarthritis by modulating the response of antigens in key immune cells and hlping to control the inflammatory process. Boron should be taken with calcium and magnesium (what I call its sisters) and perhaps also Vitamin D (what I call its cousin). A deficiency level of boron would be 1-2mg per day, a toxic level about 100-180mg per day. A normal level is probably about 3mg per day.


Cadmium is of the same chemical family as zinc and mercury. It is considered one of the 189 listed hazardous air pollutants in the US. However, food and cigarette smoke are normally our largest sources of exposure. Smokers can double their daily intake of cadmium, since about half the amount breathed in is absorbed by the lungs, whereas gut absorption is less than 20% and some recent research indicates less than 2%. Our food intake per day is about 2-40ppb (or Ug/Kg or mcg/Kg), the highest levels coming from leafy vegetables and potatoes and lower levels from fruits and beverages. Unpolluted soils normally contain about 250ppb. The risk of health damage from intake of cadmium in day-to-day foods is really non-existent.


Almost all of the calcium in our bodies (99%) is in our teeth and bones. However, we should not overlook the very important 1%, which is key in such vital functions as, nerve impulse conduction, muscle contraction, blood clotting, membrane permeability, cell division regulation, secretion of hormones and other metabolic processes. Please remember our gut (intestines) only allow a certain amount of calcium into our bodies, unless the regulation system has gone crazy, which usually does not happen. Take in huge "gobs" of calcium and usually it just goes out the other end, even if it is "chelated" or some other "wonder product".

Traditionally, we are told, we must be deficient in calcium if: we suffer from pains in our joints, muscle cramps and twitching (tetany); numbness and tingling (paresthesia), hyperirritability, convulsions, bone disorders, such as, rickets in children, osteomalitis and osteoporosis (demineralization) in adults, heart palpitations and slow pulse rates. Also during pregnancy, lactation, PMS, for aging, arthitis, during aging, insomnia and with some dental and gum disorders. However, the answer is *usually* not so *simple*. The first things to consider is *not only* absolute amounts, BUT RATIOS. Calcium *never* works in a vacuum and its "sisters (VERY close working partners/allies), cousins (close working allies/partners) and aunts" (the key metabolic systems within which it works) MUST be taken into account!!!

SISTERS: Magnesium, Vitamin D and phosphorus
Cousins: Potassium, Vitamin A, Vitamin C, lysine, arginine and lactose
Aunts: Nervous system, cellular metabolic system, skeletal system and many others

Some factors that can cause our bodies to lack calcium:

  1. High phosphorus:calcium ratio (excess calcium is removed from skeletal tissue, which demineralizes the bones and the excess calcium is excreted). High phosphorus foods include soda and diet pop and many convenience foods, for example, cheese spreads.
  2. Incorrect calcium:magnesium balance, sometimes due to imbalances in the subsystems of the body. Total balance may appear to be correct, but ratio, say, available to the muscles may be incorrect and hence, cause problems.
  3. High protein diet can increase urinary loss of calcium.
  4. Poor fat absorption, which reduces Vitamin D uptake by mucosal cells.
  5. Stress, both physical and emotional
  6. Lack of excercise.

Good natural sources of calcium include, milk and its products, dark green vegetables, nuts, seeds, grains and beans, sardines and egg yolks.

Officially Recommended Dietary Allowance (RDA) for calcium is 1.2g (grams) per day. The ratio of calcium to phosphorus is 1:1. The ratio of calcium to magnesium is officially about 1:3 or lower, although in many supplements it is 1:2.


This is one of the most interesting Trace Elements. Chromium occurs as a metal (+0), in the trivalent form (+3) which is an essential element and as the chromate (+6) which has many industrial uses. Today, I will write ONLY on the trivalent form, which is an essential trace element.

Chromium (+3) is a critical component of the glucose tolerance factor (GTF). This factor contains niacin, glycine, glutamic acid and cysteine, in addition to, chromium (+3). Chromium (+3) and insulin are both involved in glucose metabolism. Chromium (+3) is also important in the metabolism of cholesterol and is an integral part many enzymic and hormonal reactions.

The proper functioning of chromium (+3) is important in diabetes, hypoglycemia, heart disease and pregnancy. But too much is as bad as too little!!! Thus excess chronic ingestion of chromium (+3) can reverse the normal function and inhibit rather than enhance insulin activity.

Marginal chromium deficiency is now common place, particularly in the elderly and probably also in people who regularly excise strenuously and do not eat particularly healthy diets.

The major depleting factors are refined foods, refined sugars and aging. However, please do not believe all the health food store adverts, rather eat a healthy diet and watch your intake of refined foods and snacks and refined sugars.

Natural sources of chromium (+3) included, Brewer's yeast, whole grained foods, wheat germ, grape juice, molasses, mushrooms, oysters, egg yolk and thyme.

Sisters: Vitamin B3 (niacin), amino acids (glycine, glutamic acid, cysteine)
Cousins: Magnesium, zinc, Vitamin B6 (pyridoxine) cobalt, and iron
Aunts: Glucose, insulin and cholesterol

Officially Recommended Daily Allowance (RDA) - 50 to 200ug/day (50 to 200mcg/day)

Usual daily amounts eaten by the elderly seem to be as low as 10 to 25ug/day (10 to 50mcg/day) and many people have diets with amounts below 100ug/day.

What should a person do? Try to eat more whole grained rather refined products or add Brewer's yeast or wheat germ to your cooking or if you want to take a supplement, choose a plain one (no fancy amino acid chelates or GTF) and a value of about 100ug/day (100mcg/day), certainly no higher than 200ug/day (200mcg/day).

(NOTE: There have been a few reports of kidney damage at 1200 mcg/day or more taken daily for several months).


Copper is an essential element for all animals and plants. It is a co-factor in many ezymes. Copper is necessary for the absorption and utilization of iron. It helps absorb and carry oxygen as a component of the hemoglobin system. Copper functions as an important blood antioxidant. It helps maintain the integrity of cell membranes and the myelin sheath around nerve fibers, partially at least, through being a co-factor in the synthesis of phospholipids. Copper helps prevent peroxidation of polyunsaturated fatty acids (PUFA), is involved in collagen formation for bone and connective tissue and in protein metabolism healing processes of the body.

While true copper excess and deficiency diseases exist, most impaired use of copper in bodily systems is due to ratio imbalances of copper and certain other key trace elements, such as copper together with iron or iron and zinc or molybdenum and sulfate, as well as the type of carbohydrate consumed.

High intakes of zinc or calcium or Vitamin C can inhibit copper absorption, (as do mercury and silver). However, zinc deficiency can also accentuate an excess of copper.

Imbalances have been known to occur in certain bone diseases, atherosclerosis, heart disease, blood diseases and breathing difficulties.

Copper is found in nuts, wheat bran, wheat germ, Brewer's yeast, soybeans, seafood and liver and kidneys.

Sisters - Iron, zinc, molybdenum-suphate complex
Cousins - Calcium, manganese, magnesium
Aunts - Blood system, cell and nerve membranes.

Officially Recommended Dietary Allowancea (RDA) - 2mg/day
High Amounts - 3mg/gay
Super Amounts - 5mg/day


(This is a *very* hot political topic. I have given my professional opinion on this issue in years gone by and will no doubt do so again. However, in this vignette I will NOT state an opinion, but rather attempt to pose questions and give information, so that you can ask questions of the opposing sides and then make informed judgements).

Fluoride is a trace element ion and hence it has a deficiency toxicity level (which could be lower, equal or greater than the normal background level of fluoride in food plus water intake) and an excess toxicity level. The difference between these two levels is the normal safe range. Please always remember the first rule of toxicology - "Only the dose makes the poison". However, *both* toxicity levels and hence the safe range can and will be modified by a whole range of factors. Consideration needs to be given to:

  1. How much fluoride is absorbed and in what form
  2. How is it metabolized and where do the products go, does metabolism change with age and/or disease
  3. How much is retained and what is the time frame, short term and long term and
  4. What are the key factors influencing 1. through
  5. Some that immediately come to mind, are the levels of protein, magnesium, calcium phosphorus, iron, molybdenum, aluminum and Vitamin C and that is just a start!

In any human bone or tooth studies, magnesium and protein need to be considered along with calcium and phosphorus. In cancer and other human disease studies, it is also necessary to discover if *all* possible causes have been considered.

When determining legal or proposed limits it is *extremely* important to compare "apples" with "apples" and ask what assumptions have been made. How much does the adult male and female, the various ages of children and infants, weigh, eat per day and drink per day. Watch out for mg or ug per day versus mg or ug per kilogram of weight per day. If the so called "market basket" of foods is being cited, what years are being used and what is the range of values across country. Also are safety factors included, if so, what are they and how were they derived? *One very big problem in assessing data is that TOTAL INTAKE should always include food + water + toothpaste*. However, it OFTEN includes *only* water or *only* food, so watch out!

Normally, the assumption is made that an adult male weights 70kg, an adult female 55kg (although I have seen from 50 to 60kg) and that both drink 2 liters of water (liquid) per day, although in hot climates 3 liters is often used. It is also often assumed that adults eat 1kg of food per day. Children and infants are often scaled by weight off these figures.

What have to be determined are the deficiency and excess toxicity levels for (food + water). This is not as simple as it seems. For example, if we know there is a high prevalence of reduced bone density and collapsed vertebrae in humans in an area with low-fluoride water (0.15-0.30mg per liter), how do we determine the highest level at which this will not happen? And how do we build in safety factors?
(*Note* water only, so food must be added, say about 1.0 to1.5mg per day for an estimated total of 1.3-2.1mg per day).

Then at the other "end", if we know that a *total* intake of 20-50mg per day may lead to severe bone and kidney problems in humans, how again do we determine the lowest level at which this will not happen? And how again do we build in adequate safety factors? Other studies of minimal effects in humans, seem to indicate a no-adverse-effect-level (NOAEL) to a lowest-adverse-effect-level (LOAEL) of 8-10mg per day total intake of food and water.

All these studies exist, *but* none have been adequately confirmed. The problem is that the ranges between deficiency toxicity, background and excess toxicity are VERY SMALL and total intake, food plus water, are often not measured using the same groups of people (population).

A *sample* set of levels might be as follows:
Water 0.8-1.2mg per day (2 liters x 0.4-0.6mg per liter)
Food 0.2-0.3mg per day
Total 1.0-1.5mg per day or 0.02mg per kg of human weight per day
But we need estimates from both food and water (plus perhaps toothpaste) all together.

The following *Contaminant* Regulation is of interest:
EPA Maximum Drinking Water Level - 4mg per liter
EPA Integrated Risk Information System (IRIS)
No-Adverse-Effect - Level (Food plus Water) = NOAEL = 0.06mg/kg/day = 4.2mg per day
Lowest-Adverse-Effect-Level (Food plus Water) = LOAEL = 0.12mg/kg/day = 8mg per day

Recommended Dietary Allowances (RDA) are the people who are saying total intake:
Adult males - 4.0mg per day;
Adult females - 3.0mg per day
Children 7-10year - 1.0mg per day
Infants - 0.5mg per day

The food data and natural background water levels and the deficiency toxicity and excess toxicity levels need very careful accessment. Any discussion on fluoridation (AND AT WHAT LEVEL OF ADDITION, for example, 0 or 0.25mg or 0.5 or 1mg per liter) needs to have a firm basis for argument (pro or con). Please note, the discussion on fluoridation should always include a LEVEL, and a Risk Assessment.

(PLEASE always remember TOTAL oral intake = Water (2 liters) + Food (+ toothpaste) *not just one section of it*!!!)


Germanium has not been found to be an essential nutrient for humans. However, rats fed a germanium deficient diet had altered mineral composition of the bone and liver and decreased DNA in the tibia. For humans the daily dietary intake of germanium seem to be in the range 0.4-1.5 mg, mainly from vegetables, grains a fruits. There is no indication that humans become deficient. Some forms of germanium, such as the dioxide, citrate and lactate can be given in amounts toxic to the human liver and kidneys, resulting in death.


Iodine is an essential element for all mammals. About 80% of the bodies iodine is found in the thyroid. Iodine is an integral part of the thyroid hormones, thyroxine and triiodothyronine. The thyroid regulates energy production and the rate of body metabolism, including that of excess fat (thus also partially body weight).

Iodine is present in foods mainly as the iodide, but also, organically, bound to amino acids.

Iodide is rapidly and almost completely absorbed orally and also, which is unusual, via the skin.

Iodine is unevenly distributed in the environment. It is estimated that there are 1,000 -2,500 million people who suffer from iodine deficiency, mainly, "deficiency" goiter. However, in some developing countries, the deficiency may be at least partially due to the "excess" consumption of plants containing natural goitrogens, such as the staple food cassava. The goitrogens interfere in the iodine-thyroid-hormone production. These compounds are present in cabbage, rutabagas, cauliflowers, turnips and some nuts.

Just to increase the general confusion, a *high* intake of iodine can lead to another type of goiter. Normally this "toxic" intake must be greater than *1mg/day*.

Natural sources of iodine include, seafood, kelp, sea weeds, fish liver oils, eggs, cheddar cheese, peanuts, sunflower seeds and pineapples. The most usual, first world, source is iodized salt. It should be noted that iodates are sometimes used as bread dough oxidizers, iodine-containing disinfectants may be used in commercial milk production and iodine may be an additive in animal feeds.

The metabolism of iodine can be antagonized by large intakes of nitrates, resorcinol and cobalt.

The Officially Recommended Dietary Allowance (RDA) for iodine is 150ug/day (150mcg/day), with pregnant and lactating women 175-200ug/day. A high to "super" amount would be 300-400ug/day, a deficiency, for an adult, would be about 50ug/day.

Sisters and cousins - Various hormones such as, insulin, progesterone, cortisol and serotonin
Aunts - Thyroid hormones


Some of the major functions of iron include the production of hemoglobin and myoglobin, which transport oxygen in the blood and muscle, respectively, its role in collagen synthesis and its use as an enzymic cofactor, particularly in protein metabolism and in neurotransmitter synthesis for serotonin, dopamine and noradrenalin.

Iron, like several other essential elements, is actively, rather than passively, transported across the gut wall. This means that there is a regulatory system which controls the uptake of iron. Normally about 10% of the iron fed, is absorbed. The regulatory mechanism also acts as a type of "gate-keeper" - body deficient, let more iron in; body excess, cut back on iron absorbed. Now there are times when the gate-keeper does not or can not do its job properly, for example, there is a genetic condition which results in excess iron in the body, or times in our life cycle when we could be more prone to iron deficiency (infancy, adolescence and pregnancy) or the iron presents itself to the gate-keeper as an eye-catching person (correct co-factors such as Vitamin C or in the form of heme) and more iron is temporarily let in or as an ugly person (co-factors such as phytates, oxalates and phosphates) less iron is let in. But in general, the iron intake is pretty well regulated, a *fact forgotten in most lay texts* and also in some high level ones. With regard to the latter, I had a good laugh when a National Research Council (NRC) text stated, "..without genetic defects that increase iron absorption, there are no reports of iron toxicity from foods other than long-term ingestion of home brews made in iron vessels", the NRC did not realize that these particular people *actually had the genetic defect too*.

I have seen many articles claiming, iron-xyz is *the* iron product to use. Don't you believe it, unless they have well conducted absorption experiments to prove it. I have seen too many experiments where the "wonder" product comes in, well down the list of absorbability. Also, I remember too well, a series of experiments seeking to prove the iron deficiency in a particular population was caused solely by the high phytates in their food supply. Unfortunately that was only part of the puzzle.

The RDA total dietary levels plus supplementation for iron are:
Infants -- 6-10mg/day
Children -- 10mg/day
Men -- 10-12mg/day
Women -- 15mg/day
Pregnant -- 30mg/day
Lactating -- 15mg/day

In general, if you believe you need more iron in your diet, perhaps think about:

  1. A heme containing product - once was liver (I would not touch it these days),
  2. A vegetable product, high in iron and Vitamin C - dried fruits or a citrus fruit drink with red wine, (my mother as a teenager, on coming home from school, was given a glass of port - a good source of iron) be creative!!! or
  3. If you really want a pill, choose the cheapest pill with a water soluble iron compound in it. Save you money, amino-acid chelates are not the answer here!!! Also iron in the so-called "fortified" foods is usually poorly absorbed by our bodies.

Other factors to consider are:

  1. Antacids reduce iron absorption
  2. Chronic liver diseases, including alcoholism reduce absorption
  3. Deficiency in Vitamin B6 (pyridoxine) and/or zinc, mimic iron deficiency symptoms
  4. Excess zinc and/or excess Vitamin E can interfere with iron absorption
  5. Anemia is most often not just an iron deficiency

Iron's sisters are: Copper, zinc and Vitamin C
Iron's cousins are: Manganese, molybdenum, Vitamin E and Vitamin B complex
Iron's aunts are: Calcium and phosphorus, which together with iron must form a balance


Why do I call it the wonder element? It is the catalyst for more enzymes in our bodies than any other element. The magnesium activated enzymes are particularly important in the metabolism of carbohydrates, amino acids and the regulation of protein synthesis.

Magnesium plays a critical role in muscular and neuromuscular contractions, and hence, in the functioning of the heart muscles and vasodilation of the blood vesels.

Magnesium plays an important role in the regulation of cellular sodium, potassium and calcium. It helps in preventing the formation of calcium-oxalate kidney stones. It plays a major part in the initial hardening of tooth enamel and resistance to decay.

My first "knowledge encounter" with this hidden wonder element was in the 1950s, when so many women in southern Africa were dying horribly, in late pregnancy, from eclampsia. One of my mentors was involved in using an injection containing magnesium in the crisis, out in the "field", that is, in the hovels of dirt-poor townships and saving the mother and often the child too. A multi-nutrient pill containing magnesium plus other minerals (all magnesium's "sisters, counsins and aunts") was given free to as many pregnant moms as the various teams of workers could get their hands on - this helped too. Not all the pregnant women who got eclampsia were poor. At least one ex-high school classmate of mine suffered from it, but I suspect she did not eat nutritious foods during pregnancy.

Why do I say, all magnesium's "sisters, cousins and aunts"? Magnesium, chromium, cobalt, copper, fluoride, iodide, iron, manganese, molybdenum, selenium, vanadium, zinc and also calcium, potassium, sodium, phosphorus and sulfur *never* work/function on their own! They always "work" closely with or against a small group of elements and substances (sisters), are influenced by by a larger group of elements and substances (cousins), governed by bodily systems (aunts). This is also true for aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, bromide, cadmium, gallium, germanium, gold, lead, lithium, mercury, nickel, platinum, rubidium, silver, strontium, tellurium, thallium, tin, titanium and zirconium. It is *very* important to understand as much as we can about all these relationships, in fact it is *very dangerous* to our health to ignore these relationships, because health, be it on the subcellular or metabolic level or the whole person level, requires balance and moderation. ONLY THE DOSE MAKES THE POISON! Too little is often as bad as too much!!!

In 1993, I was taking part in a high level trace element conference in Europe and at the end of nearly every paper, either I or a young Prof (who it turned out was trained by one of my two PhD classmates) would jump up and ask the following two key questions:

  1. What was the standard - meaning what was the true dose, including how much was absorbed.
  2. What were the levels of x, y and z - that is, did you measure the levels of the "sisters" and what were they? Cruelly it meant, did you have a valid experiment or were your results due to a metabolic imbalance you did not know you had created.

Well, who are magnesium's sisters? Calcium, phosphorus, and Vitamin D. Whereas close cousin's include manganese, zinc, Vitamin B6 and Vitamin C. The aunt's are the muscular systems etc, described above.

What foods are high in magnesium? Whole grains, seafood, brown rice, green leafy vegitables, apples, lemons, soybeans and almonds are all good sources, but not the only ones.

Next question is obviously, should I take a supplement and if so what should I take? Ideally our foods should provide all we need. However, it does not always work out that way, for many reasons. I hope later down the series you will get a better feel for what it is correct for your own body. I need to write on absorption, excretion and metabolism. I *will* recap after I have written on calcium, copper, iron, potassium and zinc, which together with magnesium, make up what I call the major trace elements. Later I will deal with the minor trace elements, such as chromium and again recap. I will also write on the vitamins (then recap) and the major "building blocks", such as fatty acids, fats, fiber etc. So please be patient with me, because I want to give you background information, before talking about integrating the "picture" for your own particular needs.

I leave you today with some passing thoughts. Multi-vitamin-mineral pills serve the same purpose as a one-size-fits-all muu-muu. In addition, taking high levels of vitamins-minerals all the time leaves you nowhere to go when your body really need them. Also they become like a child's safety blanket - just a habit with little true safety attached, except what is in the mind, which is very important too. Yes, I do have both Vitamin and Mineral tablets in the house and I do use them, but not every day.

RDA levels:
Men - 400-420 mg/day
Women - 310-320 mg/day
Pregnancy - 400 mg/day
Lactating - 360 mg/day

Recommended "upper" limit of supplementation for men, women, pregnancy and lactating females - 350 mg/day


PLEASE NOTE: In this series on trace elements, I write ONLY about ORAL comsumption of the element and ONLY about the INORGANIC form of the element.

Manganese is a trace element we hear toxic warning about, in its *organic* forms and also about in its *inhaled inorganic* forms. But in this vignette, I am *only* talking about *oral inorganic* manganese. You may well ask, once an element gets into the body, does the body care about the route of entery or whether it was inorganic or organic? The answer is both yes and no. Crudely, with inhalation, very often the toxicity of the element(s) occurs in the lungs before they are fully absorbed into the body. Also crudely, certain organic forms of elements are often toxic because the organic part of the molecule increases the toxicity of the inorganic part and/or the whole molecule mimics an essential entity of the body in size or shape or other key property.

Oral inorganic manganese is *essential* to the mammalian body. It is involved as an enzyme catalyst in carbohydrate, mucopoly- sacharide, fat and protein metabolism, in reproduction, including sex hormone production and the functioning of the mammary glands and in the nourishment of nerve and brain cells. It is vital to thiamine (Vitamin B1) metabolism and Vitamin E utilization. Known manganese metallo- enzymes, include pyruvate carboxylase and superoxide dismutase and there are many enzymes requiring less specific catalysis by inorganic manganese.

Both human deficiency and excess toxicities exist, but rarely "happen". Little is really known about "borderline" deficiencies, because of the interlinking of nutrients which invalidates many of the normal experimental procedures. Testing for 3 or more components for interactions (say, manganese, iron, zinc - deficiency, normal, excess) is costly and seldom done. Perhaps now, as modelling improves, more can be accomplished. Model and find out certain key entities we need to test for and do those experiments first.

Manganese is present in tea, nuts, whole grain products, green leafy vegetables, bananas, apricots, blueberries, pineapples, egg yolk and brussel sprouts.

Depletion may occur from eating an excess of refined foods, excess soy protein and abnormally high amounts of calcium and phosphorus.

Sisters - Chromium, iron, choline, thiamine
Cousins - Magnesium, zinc, selenium, Vitamin E, Vitamin K
Aunts - Carbohydrate, fat and protein metabolism

Officially Recommended Dietary Allowances (RDA) - 2mg/day
High Amounts - 5mg/day
Super Amounts - 10mg/day


Mercury is of the same chemical family as zinc and cadmium. There are three forms of mercury, metallic mercury, inorganic mercury and organic mercury (including methylmercury). Metallic mercury was used in tooth filling amalgams. Health problems appear to have arisen from these mercury amalgam fillings in a small percentage of people, but are of a different type to those that can arise from the intake of methylmercury.

Among the many uses of organic mercury was its use as a fungicide on seed grains. In the early 1970s several thousand people in Iraq were poisoned, when they ate US supplied seed grain, rather than planting it. This happened elsewhere too, but not in such large numbers.

The most publicized "mercury" poisoning arises from the ingestion of fish containing methylmercury (NOT mercury), whose food chain has become contaminated with mercury from natural, industrial or waste sources. The big question becomes, "Will I get poisoned if I eat fish, every day or every week or every month?". Please remember, only the dose makes the poison, but the effect dose is modified by what else one eats (for example, how much zinc) and what the general state of ones health is, particularly, in this instance, is one pregnant. Standards have been setup based on human research on 3 communities in widely separate areas of the world and safety factors have been added.

If you feel safer eating only fish-farmed fish, with a sea fish meal thrown in as a treat several times a month, please do so. However, having your blood and/or urine tested is in my opinion a waste of money, even insurance money. Also, PLEASE do not fall for the chelation therapy fad. Chelation treatment in cases of true mercury poisoning is very specialized and the type used depends on the specific type of mercury received. Chelation therapy, particularly if you do not need it could seriously damage your health!


Molybdenum is a little known essential trace element, that is a constituent of several enzyme systems, particularly, aldehyde oxidase, xanthine oxidase and sulfite oxidase. There is also an interesting triad balance system involving molybdenum, copper and sulfur metabolism.

There are, at least, two types of known human molybdenum deficiency toxicities. Following long-term total parenteral feeding, lack of molybdenum led to an amino acid intolerance, with increased urinary excretion of xanthine and sulfite and decreased urinary excretion of uric acid and sulfate. Whereas, in the second type a rare inborn metabolic error led to a lack of molybdopterin, the molybdenum co-factor of the enzymes sulfite oxidase and also xanthine oxidase.

At the other end of the spectrum, excess levels of molybdenum (10-15mg/day) have led to a goutlike syndrome associated with high levels of molybdenum, uric acid and xanthine oxidase in human blood. However, even at 540ug of molybdenum per day (540mcg/day or 0.54mg/day) losses of copper in the urine have been observed.

In the US the average dietary intake is in the average range 100-200ug per day.

The Official Recommended Dietary Allowances are as follows:
Infants 0-0.5 years -- 15-30ug per day
Children 1-3 years -- 25-50ug per day
7-10years -- 50-150ug per day
Adults -- 75-250ug per day
Supplementation IS NOT RECOMMENDED

Sisters - Copper and sulfur
Cousins - Chromium(?), Vanadium(?), manganese(?), lead(?), tungsten(?), selenium(?) Br> Aunts - Purines and other systems involving the key enzymes of which molybedenum is the cofactor.

It is obvious more research needs to be done on this trace element. Analytical problems have deterred many a research project up to now.


(From Selene, the Greek moon-goddess, often portrayed with a scepter in her hand and riding in a chariot drawn by two white horses).

This is a particularly interesting element, because we have very well documented human cases of deficiency (toxicity) as well as, (excess) toxicity. In addition, the minute you say or think Vitamin E, the next words should be, "and selenium".

In the Western U.S.and elsewhere in the world, there are many areas where the soils are overly blessed with selenium and/or there are plants which accumulate selenium. This often leads to stock poisoning, sometimes called "alkali disease" or "blind staggers".

In Keshan, China, where they have one of the soil selenium "deficiency" spots in the world, the local people, particularly, the pregnant women and children, developed an endemic cardiomyopathy. This finding was first international presented to scientists in Perth, Australia in May 1981. It was extremely frustrating to be unable to understand a single word of the paper!!! Even written questions, proved "non-rewarding". What was also strange, was that there appeared to be no other scientist present, who spoke a common language with these particular delegates, something which was unlikely to have occurred even 5 years later!

Key uses of selenium, include binding or complexing with several heavy metals, thus protecting and detoxifying certain vital systems. It is a component of the glutathione peroxidase system, which protects against certain oxidative reactions. Selenium and Vitamin E work together in growth, fertility and other metabolic functions of the body. And selenium is involved in the general cytochrome P450 detoxification of xenobiotics, a loose term often applied to pollutants. Many people consider selenium is helpful in heart disease and as a protection against cancer. It is very difficult to prove or disprove this, since most often, key parts of the puzzle get left out. It is reasonably easy to test for 2 interlinking factors (selenium plus say, Vitamin E and the glutathionine system), but harder to test for 3 (selenium plus say, Vitamin E, the glutathione system and sulfur amino acids), etc, etc. Usually one ends up with at least 6 probable interlinking factors and the costs of experimentation go skyward and hence are unlikely to take place. Except now, as computer modelling improves, various possibilities arise, so here is hoping! Yes, I think selenium and Vitamin E, in moderation, can be of help in some "heart" problems. In certain "cancers", which are known to be probably due, in some measure, to metallic overexposure, yes, selenium could be of use, but ratios of metals to selenium and other factors need to be considered. Hence, for "heart" problems, a probable yes, and for certain "cancers", a qualified yes.

Good food sources of selenium - Brewer's yeast, nuts, cheddar cheese, sea foods, grains (if not over-purified), garlic, etc.

Sisters - Vitamin E, glutathione, arsenic
Cousins - Mercury, cadmium, copper, silver, Vitamin C, zinc, sulfur containing amino acids
Aunts - Proteins and sulfur metabolism, particularly, the enzyme systems, succinic dehydrogenase, choline oxidase and proline oxidase.

*Please remember* selenium is measure in *micrograms* per day not milligrams/day. The usual symbol for micrograms is ug, but the health food people write it as mcg, (milligrams are written as mg).

The Official Recommended Dietary Allowance (adult males) is 70ug/day;
The measured daily amounts in the normal US diet is about 50-100ug/day
Excess Toxicity might probably occur as low as the range 750-1000ug/day (0.75-1.00mg/day) - hence you want your TOTAL intake to be less than say 375ug/day, so best if you want a supplement, have one containing no more than say 200-300ug/day OR *better yet*, see that your food intake of selenium is increased.
Deficiency Toxicity would probably occur in the range 10-25ug/day BUT depends on many factors.


The trace mineral silicon is found in both plants and animals. Silicon is not currently considered to be an essential element in humans, but deficiencies have been reported in experiments performed on rats and chicks. Silicon deficient chicks had abnormalities in their bones and joints, which appeared to involve collagen and glycosaminoglycan formation. Silicon is essential for some plants. In human diets, the daily intake of silicon is in the 20-50mg range. Silicon is poorly absorbed from the diet. Claims that supplemental siliconmight be of benefit in osteoporosis and in diseases of the joints have not been confirmed.


Tin is not considered essential for humans. Tin deficiency has been created in rats, leading to poor growth, alopecia and lowering of response to sound. In humans, the daily dietary intake of tin is in the 1-40mg range. Although studies in rats have suggested that tin may have an immune-modulating activity, this has not been confirmed in humans. Supplemental tin is not recommended for humans.


Vanadium is widely distributed in nature. Vanadiun has not been established as an essential trace element in humans. However, in goats deficient animals had elevated spontaneous abortion rates and depressed milk production, whereas deficient rats had decreased growth. Vanadium compounds can mimic insulin, but since vanadium and its compounds are poorly absorbed from the gut (less than 5%) an effective oral dose would likely be toxic. However, some compounds such as vanadium-ligand-L-glutamic acid gamma-mono-hydroxamate and a picolinato compound, both of which have a higher therapeutic to toxicity ratio are being developed. The average daily intake of vanadium is about 15mcg. Chromium (+3 not +6), iron (+2) and aluminum hydroxide and chloride all decrease absorption of vanadium. It should be noted that claims that vanadium increases muscle mass have been refuted by scientific research.

ZINC - Sometimes called the Male Sexy Element.

Zinc is an important essential macro trace element required by many enzymes in our bodies. It is important for the normal function of the prostate gland, and the growth and maturity of the male sex organs, in burn and wound healing and in protein, carbohydrate and energy metabolism. High levels of zinc are present in the retina and it may be important in diseases of the macular. Zinc is also a factor in how we perceived taste and smell. In addition, it is needed for cell growth and the proper metabolism of Vitamin A and phosphorus.

As with all essential elements, deficiency diseases can exist, but they are fairly rare. In additional, our gut absorption processes actively regulate how much we absorb, thus for the most part our bodies get neither too little nor too much! However, the general rule remains, too little and also too much is bad for us.

Zinc is sometimes thought to be able to produce "wonders" on its own, for example, pop a zinc pill and cure a cold! Sorry it does not work that way. In general, you would need at a minimum, Vitamin A as well, next you would to have to fool the "gut gatekeeper" and unfortunately, a cold lasts a week, if you take pills, you may feel better, but the cold will still last 7 days!

Factors that help deplete our bodies of zinc include stress, alcohol, diabetes, high cholesterol and high amounts of copper, iron, cadmium and calcium.

Natural sources of zinc, include, oysters (hence they are sometimes called aphrodisiacs), herring, sprouted seeds and grains, pumpkin and sunflower seeds, nuts, eggs, brewer's yeast, soybeans, etc.

Sisters - Vitamin A, copper, phosphorus
Cousins - Vitamins D, C and B6, calcium and iron
Aunts - Insulin, testosterone, growth hormone, protein

In general, males require slightly more zinc than non-pregnant, non-lactating females. But please do not take supplements greater than these values.

Recommended Daily Allowances (RDA)
Males - 15 mg/day
Females - 12 mg/day
Pregnant - 15 mg/day
Lactating 16-19 mg/day

But please don't take supplements greater than these values. Home Page

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email Dr. Inge Harding-Barlow