Heavy metals are found naturally on Earth in soil, rocks, bodies of water, and in trace amounts in the atmosphere. However, human activities have altered their geochemical cycles, increasing their accumulation and potential for harm.¹ 

In this article, we'll discuss the pervasive issue of heavy metal exposure, its sources, and its significant impact on health through oxidative stress and disease development, alongside strategies for diagnosis and prevention.

Why Are Heavy Metals a Concern?

Certain metals like copper, zinc, and iron are essential in small amounts for human health. In contrast, others—lead, mercury, arsenic, cadmium, and aluminum—pose health risks even at low exposure levels.¹ 

Exposure to harmful heavy metals or toxic concentrations of safe metals can lead to cognitive impairment, several types of cancer, kidney damage, endocrine disruption, and immunological and neurological effects.² 

This article evaluates the effect of heavy metals on the body, including exposure sources, oxidative stress, and disease development. It also discusses diagnostic strategies to identify exposure and prevent damage. 

Sources of Heavy Metal Exposure 

Heavy metal exposure stems from both natural environments and human-made sources and is pervasive across the United States.²   

Everyday sources of heavy metal exposure in industrialized countries like the US include:   

• Dentistry materials used in crowns, bridges, fillings, and partial dentures 
• Prescription medicines, vaccines, contrast agents 
• Metal tungsten used in orthopedics, vascular medicine, and prosthodontics 
• Air pollution  
• Polluted food (cattle, fish, pesticide-laden produce)  
• Polluted groundwater/drinking water  
• Jewelry, cookware, lead-based paint, improperly coated containers, aluminum foil, and aluminum-containing products (health and beauty products) 

Additionally, there are many professions and hobbies with an elevated risk of heavy metal toxicity, including:   

• Fuel   
• Munitions  
• Painting 
• Rubber manufacturing   
• Industrial smelting
• Mining
• Photographic processing 
• Agriculture
• Semiconductor work  
• Welding 
• Work in waste or radioactive waste disposal sites
• Jewelry making
• Ceramics, pottery, and sculpting

The High Prevalence of Heavy Metal Exposure

Far from being rare, heavy metal exposure is a global concern. 

Both the World Health Organization (WHO)¹ and the Centers for Disease Control and Prevention (CDC)³ have highlighted the global prevalence of heavy metal exposure and its impact on health.  

Population studies indicate that most people have detectable levels of heavy metals in their bodies. Biomonitoring data from the National Health and Nutrition Examination Survey (NHANES) shows that lead and mercury are present in a significant portion of the population.⁴ 

This widespread exposure, even at low levels, is associated with various health risks, including oxidative stress, inflammation, and chronic diseases. 

The cumulative effects of low-level metal exposure over time can deplete the body's antioxidants, undermining its ability to neutralize free radicals and protect against oxidative damage.  

Antioxidants like glutathione are crucial in detoxifying heavy metals and mitigating their harmful effects. However, persistent exposure can overwhelm these defense mechanisms, leading to increased oxidative stress and various health consequences. 

How Heavy Metals Induce Oxidative Stress

Heavy metals contribute to various diseases and health issues, primarily through oxidative stress—a process that damages cells and accelerates aging. 

Oxidative stress occurs when the body experiences stress or inflammation due to an imbalance between harmful compounds called reactive oxygen species (ROS) and the body's ability to neutralize them with antioxidants. 

Over time, this imbalance can damage cells and tissues, potentially causing diseases, speeding up aging, and shortening lifespan.  

Heavy metals can induce oxidative stress through several mechanisms: 

1. Disruption of Cellular Functions: Heavy metals can interfere with cellular processes by binding to proteins and enzymes, altering their structure and function. This interference can inhibit the production of antioxidants, such as glutathione, reducing the cell's ability to neutralize free radicals. 
2. Direct Production of Reactive Oxygen Species: Some heavy metals can undergo redox cycling, directly generating reactive oxygen species. For example, redox-active metals like iron and copper can catalyze the Fenton reaction, producing hydroxyl radicals, that are highly reactive and can cause significant cellular damage. 
3. Depletion of Antioxidant Reserves: Heavy metals can deplete the body's antioxidant reserves. They increase the demand for antioxidants by elevating the production of free radicals, which in turn exhausts the available antioxidants, such as vitamins A, C, and E, and enzymes like superoxide dismutase and catalase. 
4. Inflammation and Cellular Damage: The oxidative stress induced by heavy metals can lead to inflammation and damage cellular components such as lipids, proteins, and DNA. This damage can trigger a cycle of oxidative stress and inflammation, further depleting antioxidant resources. 

How Heavy Metals Deplete Antioxidants 

Once the body is exposed to heavy metals, it’s reliant on antioxidants to remove them by neutralizing the free radicals and promoting the activity of specific enzymes.⁶ 

Yet, the heavy metals themselves deplete antioxidants, creating a vicious cycle. 

Heavy metals, such as methylmercury (MeHg), deplete the body's antioxidants by binding to critical groups within cells. These antioxidants are essential for maintaining our natural defense systems against oxidative stress.   

One example is MeHg, which specifically targets and binds to sulfhydryl (thiol) and selenohydryl (selenol) groups in proteins, impairing these proteins' functions.  

This binding disrupts the activity of key antioxidant enzymes like glutathione peroxidase (GPx) by impacting the balance between reduced glutathione (GSH) and oxidized glutathione (GSSG), tipping the scales toward a state of oxidative stress.⁶ 

When these enzymes are inhibited, the body's ability to neutralize harmful reactive oxygen species (ROS) is compromised, leading to increased cell damage.  

Continuous exposure to heavy metals, such as residing in a home with lead paint or working in a munitions factory, will, over time, deplete your body's antioxidants due to the relentless presence of these toxins.⁵ 

However, after exposure ends, the body's antioxidant levels slowly recover. It detoxifies and removes the metal using the liver and kidneys, either by binding it to bile for removal in the stool or by sweating it out via the skin's exocrine glands. 

Symptoms of Heavy Metal Exposure

Heavy metal exposure can weaken the immune system and damage DNA, leading to serious health issues, including a variety of neurological symptoms. 

These toxins deplete antioxidants, hindering the immune system’s ability to fight common illnesses such as the cold or flu. 

Further, when the body is compromised and has more heavy metals than available antioxidants to neutralize them, these unbound heavy metals can attach to and damage DNA, increasing the risk of developing various cancers.⁵ 

Free heavy metals also frequently cross the blood-brain barrier and cause damage to nerves and the myelin sheath around them, resulting in a variety of psychological and neurological inflammatory symptoms.⁵ 

Neurological symptoms can be some of the most debilitating effects of heavy metal toxicity. These symptoms can vary in severity and greatly impact an individual's quality of life. 

Neurological symptoms of heavy metal exposure include: 

• Cognitive decline 
• Memory loss 
• Ataxia 
• Tremors 
• Numbness 
• Tingling 
• Neuropathy 
• Myopathy
• Alzheimer’s disease 
• Multiple sclerosis 
• Paralysis 
• Parkinson’s disease 
• Tinnitus
• Irritability

Precision Testing for Heavy Metals

The most accurate way to identify levels of heavy metals in the body is through precision testing like Vibrant’s Heavy Metals panel. 

The Heavy Metals panel uses inductively coupled plasma mass spectrometry (ICP-MS) to test for 20 of the most harmful heavy metals and elements, including arsenic, lead, and mercury. 

View the complete markers list and key clinical messages here. 

Precision Testing for Antioxidants

In addition to testing for exposure to heavy metals, you can also test your intra- and extracellular antioxidant levels using the Micronutrient Panel. 

The Micronutrient Panel directly measures the intra- and extracellular nutrient status of common vitamins, minerals, co-factors, amino acids, essential fatty acids, and more. 

This unique panel measures levels of antioxidants and nutrients commonly depleted during heavy metal exposure. 

Both the Heavy Metals and Micronutrient panels can guide personalized detoxification plans to remove heavy metals from the body, alleviate chronic symptoms, and promote health and longevity. 

For a step-by-step guide on how to develop a detoxification food plan, see our article here. 

View the complete markers list and key clinical messages here. 

Future Directions and Research

The health ramifications of heavy metal exposure are profound, touching on nearly every aspect of physiological function and disease pathology. From contributing to oxidative stress to impairing neurological function, the evidence firmly establishes the need for heightened awareness and preventative measures against heavy metal exposure. 

Promising strategies for mitigating the effects of heavy metal exposure include the development of more effective chelating agents, antioxidants capable of crossing the blood-brain barrier, and targeted nutrition plans designed to bolster the body's natural defense systems. 

Heavy Metals and the Path to Longevity

As we gain new insights into identifying and combatting heavy metal exposure, we may not only counteract their damaging effects but also enhance our resilience against a broader spectrum of environmental toxicants, establishing a path toward a healthier, more sustainable future. 

Additional Resources

To learn more about heavy metals, read these next: 

The Link Between Heavy Metals & Autoimmune Disease 

References 

1. Rehman K, Fatima F, Waheed I, Akash MS. Prevalence of exposure of heavy metals and their impact on health consequences. J Cell Biochem. 2018;119(1):157-184. doi:10.1002/jcb.26234
2. Edelstein M, Ben-Hur M. Heavy metals and metalloids: Sources, risks and strategies to reduce their accumulation in horticultural crops. Scientia Horticulturae. 2018;234:431-444. doi:10.1016/j.scienta.2017.12.039. Available from: https://www.sciencedirect.com/science/article/pii/S0304423817307628
3. Centers for Disease Control and Prevention. NHANES 2009-2010: Cadmium, lead, & total mercury - blood data documentation, codebook, and frequencies. Centers for Disease Control and Prevention; 2011 Sept. Available from: https://wwwn.cdc.gov/Nchs/Nhanes/2009-2010/PBCD_F.htm
4. Jaishankar M, Tseten T, Anbalagan N, Mathew BB, Beeregowda KN. Toxicity, mechanism and health effects of some heavy metals. Interdiscip Toxicol. 2014;7(2):60-72. doi:10.2478/intox-2014-0009. PMID: 26109881; PMCID: PMC4427717.
5. Jan AT, Azam M, Siddiqui K, Ali A, Choi I, Haq QMR. Heavy metals and human health: Mechanistic insight into toxicity and counter defense system of antioxidants. Int J Mol Sci. 2015;16(12):29592-29630. doi:10.3390/ijms161226183

Regulatory Statement:

The general wellness test intended uses relate to sustaining or offering general improvement to functions associated with a general state of health while making reference to diseases or conditions. This test has been laboratory developed and its performance characteristics determined by Vibrant America LLC and Vibrant Genomics, a CLIA-certified and CAP-accredited laboratory performing the test. The lab tests referenced have not been cleared or approved by the U.S. Food and Drug Administration (FDA). Although FDA does not currently clear or approve laboratory-developed tests in the U.S., certification of the laboratory is required under CLIA to ensure the quality and validity of the tests.