The Adverse Health Effects Of Heavy Metals & How To Avoid Them

The health effects of heavy metals are on many people’s minds, but it is difficult to know if heavy metals are something you need to worry about. Heavy metals are naturally-occuring on earth and our bodies evolved to be able to live and thrive with tiny amounts of them. Unfortunately, our environment is no longer optimal for health; industrial processes, mining, and the use of metal-containing products has made heavy metal exposure a real health concern.

This article explains what heavy metals are, covers the adverse health effects of certain key heavy metals, offers tips to reduce heavy metal exposure, and briefly touches on heavy metal detoxification, the role of essential minerals, and chelation therapy. 

What Are Heavy Metals? 

Heavy metals are naturally occurring and have an atomic weight at least five times the density of water. Some heavy metals are important for human health and others are toxic. 

Copper, zinc, nickel, manganese, molybdenum, cobalt, selenium, iron, and chromium are heavy metals that are essential for life and only have adverse effects with excessive exposure. These metals are commonly called essential minerals, rather than heavy metals, to emphasize their importance for health and to differentiate them from toxic heavy metals. 

Other heavy metals like lithium and barium may have positive health effects when taken in small doses, though they aren’t essential for life. 

At the other end of the spectrum, we have heavy metals with no known benefits — like mercury, lead, cadmium, and arsenic — that are highly toxic, even in tiny amounts. Finally, there is tin and aluminum, which are less toxic to the human body but still problematic if they accumulate enough (1).  

Where Do Heavy Metals Come From?

As previously mentioned, heavy metals are naturally occurring in the earth’s crust. They are released into the air and water through natural processes, like rock weathering and volcanic explosions.

However, the real issue with heavy metals stems from human activities, including industrial processes; mining; pollution; agricultural activities; and wastewater from textiles, leather tanneries, sewage, etc, which cause large amounts of heavy metals to contaminate the air, soil, food-chain, and water (1). 

Common Heavy Metal Exposures

Mercury

Mercury exposure may happen when consuming seafood contaminated with methylmercury, dental amalgams, industrial processes, and certain multi-dose flu vaccines that contain thimerosal (ethylmercury) as a preservative (2). According to the Environmental Working Group (EWG) thimerosal was banned for use as a cosmetic preservative in 2007 but is still allowed in certain cosmetic products for use around the eye. 

Health effects of mercury exposure include issues with brain, nerves, muscles, kidneys, immune function, hormones, and skin. For a thorough review of symptoms, see this article: Mercury Toxicity And Treatment: A Review Of The Literature. 

Note: Thimerosal-containing flu vaccines approved by the FDA include Afluria (multi-dose), Afluria Quadrivalent (multi-dose) Fluvirin (multidose), Fluvirin (single dose), FluLaval Quadrivalent (multidose), Fluzone Quadrivalent (multidose). Thimerosal-free flu vaccines include Afluria (single-dose), Fluad (single-dose), Flublok (single-dose), Fluzone High Dose (single-dose), Afluria Quadrivalent (single-dose). Fluarix Quadrivalent (single-dose), Flublok Quadrivalent (single-dose). Flucelvax Quadrivalent (single-dose). Info retrieved from the FDA website in June 2024. 

Lead

Lead exposure occurs through lead-based paints, occupational exposure, and from lead-based hobbies (fire arms, soldering, home renovation of structures older than 1978). 

Lead is particularly damaging to children and may cause brain and neurological problems, slow growth, learning and behavior problems, hearing and speech problems, and more (3). Excess lead exposure has also been linked with hypertension (4), kidney issues (5), and reproductive issues (6,33). 

Cadmium 

Cadmium exposure may occur via cigarette smoke, contaminated foods (particularly rice and vegetables), and industrial emissions. 

Cadmium exposure increases the risk of several types of cancer; causes kidney and liver problems; damages mitochondria; and is involved with the development of diabetes, heart disease, hypertension, certain eye issues, and gum disease (7-9). Elevated cadmium levels increase the risk of miscarriage and recurrent pregnancy loss (33).

An interesting finding is that in women who took a multivitamin & mineral formula while lactating, cadmium passed through breast milk was significantly lower than in women who did not (10). 

Arsenic 

Arsenic exposure occurs through contaminated water and soil (particularly in certain regions), pesticides, and industrial processes. 

Arsenic exposure is of particular concern due to its strong association with many types of cancers, cardiovascular disease, and damaged neurological development and function. It is also associated with hypertension, diabetes, and anemia (11,12). Arsenic is a major concern for pregnant women as it crosses the placental barrier and has been associated with miscarriage, low birth weight in infants, congenital abnormalities, gestational diabetes, and anemia (13). 

Aluminum

Aluminum is everywhere in modern life and contamination may come from food additives, antiperspirants, cookware, contaminated water, and pharmaceuticals — like subcutaneous allergy desensitization injections, aluminum-containing antacids, and certain vaccines.

Though aluminum is much less toxic than the above metals, large cumulative exposures may have adverse effects, primarily concerned with neurotoxicity, inflammation, and oxidative stress (14). There is also emerging evidence of bone and reproductive toxicity (15). 

Tin

Tin, like aluminum, is a less toxic heavy metal and is something that we are routinely exposed to through canned foods, industrial processes, and contaminated water. 

High urinary tin levels may be a factor promoting obesity in some people and have shown an association with certain chronic health problems, like diabetes, though the relationship is still unclear (16). 

Assessing Heavy Metal Toxicity

Heavy metal toxicity assessment begins with a thorough medical visit where your clinician will ask about symptoms, potential exposures, lifestyle, occupation, environment, and diet. If heavy metal toxicity is suspected, testing will be performed, which may include blood, urine, hair, or stool testing, as well as imaging. 

Symptoms that may indicate heavy metal toxicity are often non-specific and can include fatigue, joint pain, digestive symptoms, brain fog, slow growth in childhood, neurodevelopmental symptoms, and more. It is important to remember that while heavy metal toxicity is a possible cause of these symptoms, it is rarely the most likely cause, and many clinicians prefer to hold off on heavy metal testing until other more likely scenarios are explored.

The exception is when there is a clear source of exposure; for example, neurological symptoms that started after renovating an older home. In this case, heavy metal testing would be a wise first step. Additionally, screening tests may be performed in the absence of symptoms if a possible exposure has occurred; for example, a child living in a home with lead paint, family members of a person diagnosed with heavy metal toxicity, etc. 

Tips For Reducing Heavy Metal Exposure

Making mindful choices is the cornerstone of reducing heavy metal exposures. Some tips to keep in mind:

1. Regularly test your drinking water, particularly if you live in an area with known heavy metal contamination. Use water filters that reduce heavy metals, if necessary. 
2. Limit foods known to be high in heavy metals, including high-food-chain fish—like shark, mackerel, and swordfish which are high in mercury; choose brown rice from California, India, or Pakistan over white rice or rice from other areas to avoid arsenic contamination, or choose alternate grains like millet or quinoa; rinse rice thoroughly before cooking; opt for organic produce when possible to avoid metals in pesticides. 
3. Use safe cookware. Opt for stainless steel, glass, or cast iron instead of aluminum or non-stick pans that may release heavy metals when heated or scratched. 
4. Read labels of cosmetics, toys, pharmaceuticals, and jewelry to avoid heavy metals.
5. Shower and thoroughly wash clothes after occupational or hobby exposure to metals. 
6. Avoid smoking and exposure to second or third hand smoke. 
7. Use a HEPA air purifier, especially if you live in an area with high levels of pollution or wildfire smoke. 
8. Advocate for and support stricter environmental regulations; much of the global and local reduction in heavy metal toxicity is through changes mandated by the government. 

Chelation Therapy For Detoxing Heavy Metals

Chelation therapy is a treatment choice for heavy metal toxicity (17). In this type of therapy, a chelating agent is administered either orally or intravenously, which then binds to the metal so that it can be excreted from the body. 

Chelators may bind to and deplete essential minerals as well as heavy metals, so this type of therapy must be monitored by a professional, especially for children because chelation-induced mineral deficiencies may have serious long-term effects (18). 

Herbal Chelating Agents In Heavy Metal Detoxes

Herbal chelating agents commonly found in natural heavy metal detoxes include chlorella (19), spirulina (20,21), cilantro (22), maitake mushroom (23,24), garlic (35), turmeric, ginger (36), and others. These herbs are generally less potent than their pharmaceutical counterparts, meaning they likely carry less risk for mineral deficiency when used appropriately. Therefore, while herbal chelating agents may not be appropriate choices for treating outright heavy metal poisoning, they may be a better choice for mitigating the effects of our usual everyday heavy metal exposure. 

Essential Minerals & Heavy Metals

Supplements, especially those containing minerals, have the potential to help reduce the negative effects of heavy metals, and they also have the potential to be a source of heavy metal contamination. 

First, the good news: Multivitamins that contain minerals and/or multimineral formulations have the potential to reduce some — but not all — of the negative effects of heavy metal exposure (25). 

This is because, in our bodies, heavy metals and essential minerals compete for binding sites and absorption. When there are more minerals in the diet, they win more of the competition, meaning that heavy metals have less opportunity to be absorbed, bind to cellular structures, disrupt biological systems, or build up in the body (25). 

• Mercury competes with selenium (26)
• Lead competes with iron, calcium, and zinc (27-30)
• Cadmium competes with zinc and calcium (31,32)

It is worth noting that it doesn’t matter where your minerals come from, so a multivitamin-mineral formula isn’t essential as long as you’re consuming a varied diet full of mineral rich foods. Check out these articles about food sources of iron and zinc. 

Now, the bad news: Multivitamins and herbal supplements can be a source of heavy metal intake (34). This is why Dr. Green Life products are third-party tested, and the results are posted online for each of our products. Take a look at our test results here. 

Summary

Heavy metals are prevalent in our environment and may cause harm if we are exposed to high enough levels. Chelation therapy is used to treat heavy metal toxicity, while some herbs may be useful in helping our bodies cope with everyday heavy metal exposures. Consuming adequate minerals through diet and supplementation is an important way to reduce the bioaccumulation and impact of heavy metals in the body. 

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