The use of heavy metals in industrial, domestic, agricultural, medical, and technological applications has led to a dramatic increase in our exposure. While elements, such as chromium (Cr), iron (Fe), magnesium (Mg), and manganese (Mn) are essential nutrients, studies show that chronic exposure and accumulation to heavy metals might lead to dysfunction and disease. 

According to the U.S. Environmental Protection Agency and the International Agency for Research on Cancer, heavy metals are known to induce multiple organ damage, even at lower levels of exposure. Take mercury for example. It can be found in the flesh of fish, especially in canned fish or tuna. Long-term exposure to mercury-contaminated fish and seafood might have persistent effects on cognitive function. [Environ Res. 2008 Nov;108(3):334-9]

Although studies on the effect of heavy metals accumulation show conflicting results, the U.S. Agency for Toxic Substances and Disease Registry (ATSDR) reported that inorganic or elemental mercury may promote a decline in cognitive function by inducing oxidative stress, lipid peroxidation, and mitochondrial dysfunction.

Another potentially harmful heavy metal is lead. Lead can circulate in the blood, accumulate in bones, and cross the blood-brain barrier, where it might increase oxidative stress, stimulate the death of neurons, and affect brain function. [Environ Health Perspect. 2007 Mar; 115(3):483-92]

Heavy metals accumulation might also lead to hormonal imbalance and endocrine disruption. A study published in 2014 in the Journal of Environmental Health Perspectives reported that pregnant women from lead-exposed towns had lower mean free thyroxine (FT4), higher mean TPO antibodies, together with higher lead concentration. The study suggested that chronic lead exposure might stimulation an autoimmunity thyroid condition (a condition referred to as Hashimoto).

Can heavy metals cause chronic inflammatory conditions?

The short answer is yes. 

Chronic exposure to lead, for example, even in small amounts, may be a risk factor in the development of chronic inflammation and autoimmune conditions, such as multiple sclerosis, rheumatoid arthritis, or systemic lupus erythematosus (SLE). [Neuro Endocrinol Lett. 2003 Feb-Apr; 24(1-2):65-7]

There are several theories for the mechanism of this inflammatory reaction to heavy metals, including an increase in free radicals, resulting in DNA damage, and depletion of protein (sulfhydryls) that protects your cells from damage, such as glutathione. This process may trigger an inflammatory reaction. (Current Medicinal Chemistry, vol. 12, no. 10, pp. 1161–1208, 2005)

Where do we get exposed to most of the heavy metals?

There are several sources of possible contamination in our and our patients’ environment. The number one source of lead poisoning in children is reported to come from dust and chips from deteriorating lead paint on interior surfaces. [Environ Res. 1998 Oct; 79(1):51-68]

Adults may absorb 35 to 50% of lead through drinking water. (Lead: Chemistry, Analytical Aspects, Environmental Impacts, and Health Effects. Netherlands: Elsevier Publication; 2006. pp. 158–228)

Furthermore, approximately 80% of mercury vapor is released from amalgams (dental fillings) and is absorbed through inhalation. (Journal of Dental Research, vol. 67, no. 9, pp. 1235–1242, 1988)

A study published in 2006, reported that individuals with more amalgam fillings have higher mercury levels in several tissues including the brain, thyroid, and pituitary glands. [Am J Forensic Med Pathol. 2006 Mar; 27(1):42-5; Environ Health. 2007 Oct 11; 6:30]

How to properly measure levels of heavy metals?

Measurement of levels of heavy metals might include testing of blood, urine, hair, or fecal samples. Since levels of heavy metals can fluctuate daily, we do not recommend using blood samples. 

According to an article published in the Journal of Occupational Medicine and Toxicology, no correlation was found between mercury levels in blood or urine and levels in body tissues or the severity of clinical symptoms. [Journal of Occupational Medicine and Toxicology (London, England). 2011;6:2]

Although controversial, hair analysis might be the most effective way to conduct testing for levels of heavy metals for certain elements. Hair analysis for heavy metals is affordable for most patients and is a simple and non-invasive test. [International journal of environmental research and public health, 14(8), 914; Maedica, 6(4), 247–257; Toxicology and Industrial Health. 2006 Oct;22(9):381-93]

How can I treat heavy metals accumulation?

There are several factors to consider when addressing environmental exposure. The first question we must ask ourselves is: ‘is the patient still exposed to these elements through their diet, environment, or lifestyle?’ A study published in 2017 reported that diet and lifestyle were the strongest factors that led to higher amounts of heavy metals. [PLoS ONE 12(12): e0189169]

Therefore, the first step must be reducing the accumulation of heavy metals and other environmental factors from water, food, and the patient’s environment. The second step should be to support the elimination and detoxification pathways to allow a reduction in these chemicals. The third would be nutrients and herbs that could support a reduction in inflammation and oxidative stress, reduce inflammation, and support healthy function. This should be done with a professional healthcare provider who was trained in Functional and Nutritional Medicine.

Interested in learning Functional and nutritional medicine?

During the Functional Medicine Certification Course, our trainers Tal Cohen, DAOM, MS-HNFM and Heather Zwickey, Ph.D. will teach you about environmental chemicals, their effect on the immune system and chronic inflammation, and recommendations for nutritional, lifestyle, and herbal supplements to guide your patients toward better health. 

Heather Zwickey, Ph.D. is a researcher and professor of immunology. She earned a Ph.D. in Immunology and Microbiology, completed a postdoctoral fellowship at Yale School of Medicine, and established the Helfgott Research Institute for research in integrative medicine. She holds a teaching position in multiple universities and colleges.

Tal Cohen, DAOM, MS-HNFM is an author, presenter, and a healthcare provider with 16 years of clinical experience. He is the author of several books and patient guides, including ‘Treating Pain and Inflammation with Functional Medicine: The Complete Clinical Guide’ and ‘The Complete Guide to Removing Toxins & Improving Your Health.’ Tal completed a Master of Science in Human Nutrition and Functional Medicine and a Doctorate in Acupuncture and Oriental Medicine. 

Resources:

• Berglund, L. Pohl, S. Olsson, and M. Bergman, “Determination of the rate of release of intra-oral mercury vapor from amalgam,” Journal of Dental Research, vol. 67, no. 9, pp. 1235–1242, 1988. 
• Afridi HI, Kazi TG, Jamali MK, Kazi GH, Arain MB, Jalbani N, Shar GQ, Sarfaraz RA. Evaluation of toxic metals in biological samples (scalp hair, blood and urine) of steel mill workers by electrothermal atomic absorption spectrometry. Toxicol Ind Health. 2006 Oct;22(9):381-93.
• Agency for Toxic Substances and Disease Registry. Toxicological profile for mercury (update) Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service; 1999.
• Blaurock-Busch, E., Amin, O. R., & Rabah, T. (2011). Heavy metals and trace elements in hair and urine of a sample of arab children with autistic spectrum disorder. Maedica, 6(4), 247–257.
• Bornschein RL, Succop P, Mahaffey KR, Dixon S, Galke W, Rabinowitz M, Farfel M, Rohde C, Schwartz J, Ashley P, Jacobs DE. The contribution of lead-contaminated house dust and residential soil to children’s blood lead levels. A pooled analysis of 12 epidemiologic studies. Lanphear BP, Matte TD, Rogers J, Clickner RP, Dietz B, Environ Res. 1998 Oct; 79(1):51-68.
• Bradl H, editor. Heavy Metals in the Environment: Origin, Interaction and Remediation Volume 6. London: Academic Press; 2002.
• Chang JW, Pai MC, Chen HL, Guo HR, Su HJ, Lee CC. Cognitive function and blood methylmercury in adults living near a deserted chloralkali factory. Environ Res. 2008 Nov;108(3):334-9. doi: 10.1016/j.envres.2008.06.006.
• Cumulative lead dose and cognitive function in adults: a review of studies that measured both blood lead and bone lead. Shih RA, Hu H, Weisskopf MG, Schwartz BS. Environ Health Perspect. 2007 Mar; 115(3):483-92.
• Dental amalgam and mercury levels in autopsy tissues: food for thought. Guzzi G, Grandi M, Cattaneo C, Calza S, Minoia C, Ronchi A, Gatti A, Severi G. Am J Forensic Med Pathol. 2006 Mar; 27(1):42-5.
• Dental amalgam as one of the risk factors in autoimmune diseases. Bártová J, Procházková J, Krátká Z, Benetková K, Venclíková Z, Sterzl I. Neuro Endocrinol Lett. 2003 Feb-Apr; 24(1-2):65-7.
• Flora SJS, Flora GJS, Saxena G. Environmental occurrence, health effects and management of lead poisoning. In: Cascas SB, Sordo J, editors. Lead: Chemistry, Analytical Aspects, Environmental Impacts and Health Effects. Netherlands: Elsevier Publication; 2006. pp. 158–228
• Fløtre CH, Varsi K, Helm T, Bolann B, Bjørke-Monsen A-L (2017) Predictors of mercury, lead, cadmium and antimony status in Norwegian never-pregnant women of fertile age. PLoS ONE 12(12): e0189169. https://doi.org/10.1371/journal.pone.0189169
• Liang, G., Pan, L., & Liu, X. (2017). Assessment of Typical Heavy Metals in Human Hair of Different Age Groups and Foodstuffs in Beijing, China. International journal of environmental research and public health, 14(8), 914. https://doi.org/10.3390/ijerph14080914
• Valko, H. Morris, and M. T. Cronin, “Metals, toxicity and oxidative stress,” Current Medicinal Chemistry, vol. 12, no. 10, pp. 1161–1208, 2005.
• Mercury in human brain, blood, muscle and toenails in relation to exposure: an autopsy study. Björkman L, Lundekvam BF, Laegreid T, Bertelsen BI, Morild I, Lilleng P, Lind B, Palm B, Vahter M. Environ Health. 2007 Oct 11; 6():30.
• Mutter J. Is dental amalgam safe for humans? The opinion of the scientific committee of the European Commission. Journal of Occupational Medicine and Toxicology (London, England). 2011;6:2. doi:10.1186/1745-6673-6-2.