Heavy Metal Toxicity

The term “heavy metal” assumes a variety of different meanings throughout the different branches of science. Although “heavy metal” lacks a consistent definition in medical and scientific literature, the term is commonly used to describe the group of dense metals or their related compounds, usually associated with environmental pollution or toxicity. Elements fitting this description include lead, mercury, and cadmium.

While data from the National Health and Nutrition Examination Survey shows a decade of encouraging year-over-year decreases in acutely toxic heavy metal exposure in the United States, there are still a significant number of people with blood levels that may put them at risk for chronic accumulation, and therefore toxicity, over time. For example, in the United States, children are exposed to lead in at least 4 million households. Children are particularly sensitive to lead intoxication, both acute and chronic, and there is no identified safe level of lead exposure in children Further, pregnant women risk toxic exposure to the developing fetus since the mobilization of stored lead from the mother’s bones can leach into the bloodstream, and this is more likely the result of chronic rather than acute lead exposure in the mother. With several toxic metals lacking robust pathways for elimination or otherwise remaining in the body for a long time, body burdens of some toxic metals (eg, lead, mercury, cadmium) increases with age.

Heavy metals (including lead, cadmium, mercury, and the metalloid arsenic) are persistent in the environment and have documented potential for serious health consequences. Heavy metal toxicity may damage:

• central nervous system
• cardiovascular system
• gastrointestinal system
• lungs
• kidneys
• liver
• endocrine glands
• bones

Fortunately, integrative interventions like selenium and garlic have been shown to decrease the buildup and increase the excretion of toxic heavy metals.

Risk Factors for Toxic Metal Exposure

Lead:

• Lead-containing plumbing
• Lead-based paints (in buildings built before 1978 and is the predominant source for children)
• Foods grown in lead-rich soil

Mercury:

• Eating fish or shellfish contaminated with methylmercury (includes shark, swordfish, king mackerel, tile fish, bass, walleye, pickerel)
• Breathing contaminated workplace air or skin contact during use in the workplace
• Release of mercury vapor from dental amalgam fillings

Cadmium

• Tobacco smoke
• Eating foods containing cadmium (levels are highest in grains, legumes, and leafy vegetables, fish and shellfish)
• Contact with cadmium from household products (electric batteries and solar panels)

Signs and Symptoms

These can be similar to other health conditions and may not be immediately recognized as due to heavy metal toxicity:

• Nausea
• Vomiting
• Diarrhea
• Abdominal pain
• Central nervous system dysfunction
• Heart problems
• Anemia

Diagnosis

• Blood testing
• Urine testing
• Hair and nail analysis

Therapies

• Chelation therapy, which enhances the elimination of metals (both toxic and essential) from the body, including:
  • DMPS, an oral medication for arsenic, cadmium, and mercury toxicity
  • Succimer (DMSA), an oral medication for mild-to-moderate lead, arsenic and mercury toxicity
  • Calcium-disodium EDTA for lead encephalopathy and lead poisoning

Dietary and Lifestyle Changes

• Avoid or replace mercury amalgam dental fillings with mercury-free composite material.
• Maintain nutrient sufficiency, as adequate intake of essential trace minerals may reduce toxic metal uptake.
• Limit consumption of high-mercury fish to no more than 1 serving/week.  (Consider using fish oil supplements as a substitute).

Integrative Interventions

Several dietary constituents have been investigated for their ability to mitigate metal toxicity. They work by reducing or inhibiting metal absorption from the gut, binding up toxic metals in the blood and tissues to help draw them out of the body, or reducing free-radical damage (a significant contributor to the pathology caused by heavy metals). Most studies have been limited to animal and cell culture models, although the results of human studies have been encouraging.

• Selenium: Selenium is an inhibitor of mercury accumulation and increases excretion of mercury and arsenic
• Vitamin C: A free-radical scavenger that has been shown to reduce lead levels in humans
• Folate: Higher blood folate levels in pregnant women were associated with lower blood mercury and cadmium levels
• Garlic: Garlic lowered lead levels in the blood of industrial workers as effectively as the chelator d-penicillamine
• Alpha-Lipoic Acid and Glutathione: In preclinical studies, these compounds reduced the adverse changes in blood parameters due to lead, cadmium, and copper.

This article was condensed from LifeExtension.com for Dr. David Jensen.

Tags: heavy metals, Nutrition, Probiotics, Supplements