Heavy Metal Toxicity is Responsible for Part of the Autistic and ADD Epidemic

In Dr. Henry Schroeder’s Book About Heavy Metals and Health, The Poisons Around Us, he Stated: 

"the five toxic trace metals, -- cadmium, beryllium, antimony, mercury, and lead -- are extremely important to the health of the public, being involved in at least half the deaths in the U.S. and much of the disabling disease."

The Best-Defined and Most Clinically Important Relationships Between Nutrition and Toxic Metals are Shown Below

These are the most studied metal-nutrient interactions, and there's both experimental and clinical evidence that the nutritional factors have an impact on health outcomes from toxic metal exposures.

Toxic metal-nutrient interactions: Health effect

• Lead opposes calcium, iron, zinc: Cognitive and behavior effects in children
• Cadmium opposes zinc, iron: Nephrotoxicity (kidney toxicity)
• Mercury opposes selenium: Central nervous system toxicity

For the three toxic metals, lead, cadmium, and mercury, humans have no nutritional requirement. With any level of tissue concentration, there's some toxic effect. The severity of toxic effects increases with the dose.

Metals are the Oldest Known Toxin

Many of the metals that are of toxic concern today have only been recently exposed to humans. Cadmium was first recognized in 1817.

The most significant sources of cadmium today are food: cereals, grains, leafy green vegetables, and tobacco.

Other sources include:

• fallout from the air
• cadmium content of water used to irrigate fields
• cadmium added to fertilizers
• cadmium contained in phosphate fertilizers.

These sources present a constant, daily exposure to cadmium that contributes to an ever-increasing bio-accumulation in body tissues of this toxic metal.

Historically, the toxic effect of metals was considered only during acute, high dose exposures that created significant reactions in the body.

But, today occupational and environmental standards prevent such significant exposures.

More important today, is the growing interest in subtle, chronic, or long-term effects in which cause-and-effect relationships are not obvious or may be sub-clinical

(see Concept of Thresholds for Toxic Effects)

Get Free Adobe Reader for many of my articles.

More information and research are necessary to develop methods of detection for sub-clinical defects from toxic metals. Since the damage created from exposure is usually at the level of cellular enzymes, it is important to develop additional biological indicators of cellular toxicity.

Factors Influencing Toxicity of Metals 

Most metals affect multiple organ systems, and the specific target of their action is biochemical processes, usually enzyme activity and membranes of cells and organelles.

Cells that are involved in the transport of metals, such as those of the gastrointestinal tract, liver, or kidney, are very likely to experience a toxic effect from exposure to heavy metals.

Age, diet, and the interaction with, and exposure to, other toxic heavy metal all influence the total toxic concentration and individual experiences. Young children and the elderly are more susceptible than adults to toxicity at any particular level of heavy metal exposure.

Dietary factors influence heavy metal toxicity:

• low protein intake increases cadmium and lead toxicitya
• dequate intake of Vitamin C reduces lead and cadmium absorption
• a decrease in dietary calcium will influence toxicity of major toxic metals, including lead and cadmium.

Toxic Effects of Metals

• metals affect multiple organ systems
• targets are specific biochemical processes
• they block sulfhydryl groups on enzymes
• they disrupt normal membrane activity of cells
• they disrupt intracellular organelles
• they introduce multiple mechanisms of toxicity

Here are some links to other pages about specific heavy metals.