Detox considerations for amalgam induced mercury toxicity

Detox considerations for amalgam induced mercury toxicity

It is estimated that currently one in ten people have amalgam restorations in their mouth, tooth fillings that are 50% mixed metals and 50% mercury, something that more than thirty years ago the World Health Organization recognized as “the biggest source of mercury, exposing the people to mercury levels significantly exceeding those set for food, air and water” (Jirau-Colón et al., 2019). Higher mercury levels in blood and urine have been strongly associated with the number of amalgam fillings in a large 23 year-long German study, which also noticed a trend of decreasing mercury levels over the years in parallel with the trend of moving slowly away from amalgam fillings in dental practices (Bartel-Steinbach et al., 2022).

Elemental mercury vapors from amalgam fillings are highly absorbed in the lungs and,  because of their high fat solubility, pass quickly through to the blood and “[attach] to sulphydryl groups on proteins which facilitate [its] subsequent distribution … through the body” and can from there cross the blood brain barrier and placenta (Crowe et al., 2017). Intracellularly, elemental mercury is oxidized to inorganic mercury ions (Crowe et al., 2017). Mercury ions can change protein structures and affect enzyme activities (Berlin, 2020). In the oral cavity, elemental mercury is methylated and converted to organic mercury by the oral bacteria (Jirau-Colón et al., 2019), which like elemental mercury can cross the blood brain barrier (Bjørklund et al., 2020). Mercury in all its forms is considered toxic (Mehrandish et al., 2019). A very unethical prospective case-control study measured mercury levels in patients before and at several timepoints in the two weeks following amalgam placement and found that the amalgam group had mercury levels that were “higher than the non-amalgam users and exceeded the permissible limit set for the Hg concentration in the biological samples by WHO” (Gul et al., 2016). People with amalgam fillings absorb 16-70 times more mercury daily than people without amalgam who are only exposed to the naturally low levels of mercury found in the environment (Bates, 2019).

An ex-vivo study found that there is a twofold increase in mercury leakage in the presence of electromagnetic fields/ WIFI, citing also other studies that made similar observations on X-ray and MRI exposure, in humans and ex-vivo (Paknahad et al., 2016). These findings have been confirmed by a recent systematic review (Keshavarz et al., 2022). Some researchers theorize that this contributes to the epidemiology of autism as a result of increased mercury leakage from a mother’s amalgam restorations and mercury exposure in utero has been linked to autism (Mortazavi et al., 2016); Indeed, an Egyptian case-control study found that 70% of the 40 autistic children studied had mothers who had amalgam fillings during pregnancy, while none of the mothers of the children in the control group had amalgam fillings (Khaled et al., 2016).

Amalgam induced toxicity does not present in the same intensity in all people, and certain health conditions or genetic traits could affect the severity of side effects one would experience as a result of amalgam restorations (Bjørklund et al., 2020). Mercury could impair heme production for people with CPOX4 gene variants and people BNDF gene variants could also be more vulnerable to even low levels of mercury (Mutter, 2011). Other genes that influence mercury metabolism are GCLC, MT1M, and MT4 (Jirau-Colón et al., 2019).

APO-E protein variant also plays a role; APO-E 2 protein has to “two cysteines with metal binding sulfhydryl-groups” as opposed to the  4 variant which has none, and it is believed that this is why the first genetic variant decreases while the later one increases the risk for Alzheimer’s, because of the different ability of the types of this protein to remove heavy metals, like mercury, from the CSF (Mutter, 2011). While not a protein, glutathione also contains cysteine with sulfhydryl-groups, and people with genetic polymorphisms that affect glutathione production such as the Glutathione-S-Transferase gene could have lower glutathione levels and might be therefore more susceptible for amalgam side effects, seeing that mercury needs to be bound either to glutathione or selenium to be excreted from the body (Mutter, 2011).

In addition to Autism, amalgam fillings have been linked to a variety of chronic diseases and is sometimes recognized as a potential risk factor for developing them: both retrospective and prospective studies have found increased incidences of Parkinson’s disease in correlation to amalgam fillings, with limited evidence connecting amalgam fillings to Alzheimer’s, Multiple Sclerosis and infertility (Bates, 2019; Prochazkova et al., 2004). Symptoms that have been linked to amalgam fillings include “Chronic fatigue, headache, migraine, increased susceptibility to infections, muscle pain, lack of concentration, digestion disorders, sleeping disorders, low memory capacity, joint pain, depression…” (Mutter, 2011).

In their review, Bjørklund et al. (2020) cite several case studies and a review that found that mercury, alone or along with other heavy metaly, to be inductive of autoimmunity. A case series/ comprehensive review on autoimmunity caused by foreign material in the body finds that “ amalgams may act as a first or second “hit” and induce these kinds of disorder” (Alijotas-Reig et al., 2018). Several studies found regression of several symtoms and autoimmune conditions post amalgam replacement (Bates, 2006; Björkman et al., 2022; Kristoffersen et al., 2016; Lichtenberg, 1993 ; Lindh et al., 2002; Melchart et al., 2008; Prochazkova et al., 2004; Sterzl et al., 2006; Zwicker et al., 2014).

Mutter (2011) points out the very obvious and unfortunate fact that the only way to know if there is mercury toxicity in an organ/tissue, the only accurate way to diagnose it is through autopsy, which is not an option for the living. Still, these autopsy data are invaluable as they show empirically that mercury leeches from amalgam fillings to a variety of tissues in a way that is not observed in those without those fillings. To cite a few of the scarce postmortem studies, some found that brain and thyroid tissues of deceased subjects had more mercury levels the more amalgam fillings they had in their mouths (Björkman et al., 2007; Guzzi et al., 2006; Nylander et al., 1987), proving that amalgam fillings are a risk factor for heavy metal body burden. While the authors of the most recent autopsy finding concludes that there is “no correlation between the presence of amalgam fillings and brain Hg level” (Ertaş et al., 2014), closer reading of the paper and data makes it impossible to agree with such a statement because the authors present no p values or statistical analysis of the data, the methodology is extremely flawed as they only looked at the parietal lobe and they did not have actual dental records to see if control subjects had amalgams replaced or how long anyone had had amalgam fillings, control group subjects had missing teeth, and still, 6 out of 10 amalgam treated but only 8 out of 22 of the subjects without amalgam at the time of death had detectable mercury levels in the autopsied brain tissue. Without statistical analysis it is hard to understand how a difference in 0.06 mcg/g in mean levels between the two groups is significant, yet it is interesting that, despite the previously mentioned methodological flaws, the maximum concentration of mercury detected in the amalgam group was 2.34 mcg/g, yet in the control group it was 1,76 mcg/g.

There is no autopsy study or a systematic review or metanalysis of such to date that says “we have looked at a variety of tissues and organs at once, had complete dental histories of the subjects/controls and their birth mothers, excluded those with occupational exposure to mercury, and found that there is no correlation between tissue mercury levels and number of amalgam fillings over a period of time, and can therefore say with certainty that amalgam fillings are not a significant contributor to mercury load” (not an actual quote, 2022).

Still, there are some methods for the living to assess how mercury from amalgam is showing up in their bodies. Taking blood samples over time, before and up to a year post removal, has revealed that mercury levels decline steadily once the amalgam restoration has been safely replaced (Ekstrand et al., 1998). It was through blood and urine samples that the researchers of the large epidemiological study cited earlier (Bartel-Steinbach et al., 2022) monitored mercury levels, so these two measure can be utilized and can also be helpful to evaluate a client/patient’s condition before and after safe amalgam replacements. A study that found that patient complaints improved a year post amalgam removal found that mercury urine levels declined steadily, even if levels were not considered high to begin with (Zwicker et al., 2014).  A recent study from Iran found that hair mercury levels were significantly higher in people with amalgam fillings (Rafiee et al., 2022), suggesting that a hair analysis could reveal how much mercury a body is holding and excreting. Another one on women only found that hair analysis coupled with superoxide dismutase-1 activity analysis could reveal if a woman is experiencing mercury induced oxidative stress, as increased levels of SOD-1 could show the body is upregulating this enzyme to address this issue (Cabaña-Muñoz et al., 2015).

MELISA testing, which tests how memory lymphocytes react to mercury, is a test that can detect hypersensitivity and a specific immune reaction to mercury when the results show a stimulation index higher than 2, and it has been used as an objective way to assess the body’s immune reaction to mercury before and after amalgam removal in autoimmune patients (Prochazkova et al., 2004). A study on autoimmune thyroiditis patients with positive MELISA test showed that amalgam removal led to a decrease in thyroid antibodies (Sterzl et al., 2006).

It is beyond the scope of this paper to discuss the details of safe amalgam removal, but it is crucial to point out that improper removal without the use of a rubber dam, among other precautionary measures, exposes the patient to a high load of mercury. Safe amalgam removal causes less blood mercury peaks (Halbach et al., 1998) during the procedure and less mercury in fecal excretions (Ekstrand et al., 1998) after.

While amalgam is still in the mouth, studies have found that chewing hard boiled eggs and avoiding chewing gum decrease the load from mercury vapors (Chapman & Chan, 2000).

To help the body metabolize and detox the mercury after prolonged exposure, several nutraceutical agents and nutritional interventions have been found to be helpful. Sulfur rich foods like broccoli, onions and garlic especially have been proven effective in enhancing mercury detoxification (Mehrandish et al., 2019), with the researchers also mentioning studies on cilantro that showed that it enhanced mercury clearance, albeit less effectively than garlic and milk thistle. Other helpful foods that decrease oxidative stress and trap heavy metal are turmeric and green algae in the form of chlorella (Mehrandish et al., 2019). A Spanish trial using a specific supplemental regiment that contained among other things chlorella with other algae and fiber, a formulation of multi minerals and vitamins containing selenium, zinc, b vitamins and taurine, and a formulation of numerous food extracts from foods like artichoke and dandelion found that it decreased mercury and heavy metal load over 3 months as patients had their old amalgams and dental implant safely removed and a decrease in SOD-1 levels was interpreted as a decrease of oxidative stress (Merino et al., 2019). Interestingly, even though selenium was part of the regiment, Se levels were lower after the intervention, but the Se/Hg ratio was higher, suggesting that the higher Se levels at baseline reflect the body’s way of dealing with excess mercury by binding it to selenium to mitigate toxicity, and the higher ratio with intervention meaning that the supplemental regiment is successful in metabolizing and eliminating mercury (Merino et al., 2019).

A recent review that compares traditional western medicine thiol chelators like dimercaprol and its derivatives DMPS and DMSA to selenium and acetylcysteine found that dimercaprol often has negative side effects and can cause mercury to redeposit in the brain, and its derivatives are helpful in removing mercury from blood and the kidneys, but cannot penetrate the brain and other tissues (Spiller et al., 2021). NAC is similar in that it can complex with mercury in the kidneys to eliminate it, but offers more advantages as it can demethylate organic mercury and it can cross the blood brain barrier, where its beneficial effect of increasing glutathione production means that glutathione can complex with organic mercury to facilitate its exit from the brain, but it cannot do so for mercury ions (Spiller et al., 2021). On the effects of selenium, Spiller et al. (2021) write that it can restore the action of selenoproteins which are affected by mercury, protect the DNA, increase GSH production and as previously mentioned, selenium is a shuttle that removes mercury. They find the effects of selenium and NAC to be synergistic and suggest different protocols of different doses depending on the form of mercury that needs to be detoxed and patient’s symptomology. A trial on post amalgam removal protocols found the following protocol to be helpful in increasing antioxidant capacity and reducing symptoms: Vitamin C 1900 mg/day ,Vitamin B-complex: B1 30 mg/day, B2 30 mg/day, Niacin 150 mg/day and B6 6 mg/day, pantothene 30 mg/day , Vitamin E 400–600 mg/day and sodium selenite 400 μg/day (Lindh et al., 2002).

On a last note, fiber acts as a chelator of heavy metals and can help enhance the detoxification process along with other interventions to reduce the possibility that mercury will recirculate from the gut back to the body (Mehrandish et al., 2019). My approach to a post amalgam removal protocol would therefore focus first on a client’s bowel movement regularity and adequate hydration to ensure first and foremost that mercury can be excreted. Foods to increase would be garlic and cilantro, as well as the use of chlorella as a chelating agent. Depending on the client’s bio-individual needs, I would recommend supplemental glutathione, selenium, NAC, B vitamins, and vitamin E, and request that the client monitor their blood, urine and/or hair mercury levels over time with their physician to assess the effectiveness of their tailored protocol.


Alijotas-Reig, J., Esteve-Valverde, E., Gil-Aliberas, N., & Garcia-Gimenez, V. (2018, 2018/02/01). Autoimmune/inflammatory syndrome induced by adjuvants—ASIA—related to biomaterials: analysis of 45 cases and comprehensive review of the literature. Immunologic Research, 66(1), 120-140.

Bartel-Steinbach, M., Lermen, D., Gwinner, F., Schäfer, M., Göen, T., Conrad, A., Weber, T., von Briesen, H., & Kolossa-Gehring, M. (2022, 2022/05/01/). Long-term monitoring of mercury in young German adults: Time trend analyses from the German Environmental Specimen Bank, 1995–2018. Environmental Research, 207, 112592.

Bates, M. N. (2006, 2006/07/19/). Mercury amalgam dental fillings: An epidemiologic assessment. International Journal of Hygiene and Environmental Health, 209(4), 309-316.

Bates, M. N. (2019). Dental Amalgam Fillings: An Under-Investigated Source of Mercury Exposure☆. In J. Nriagu (Ed.), Encyclopedia of Environmental Health (Second Edition) (pp. 25-36). Elsevier.

Berlin, M. (2020, 2020/12/01/). Mercury in dental amalgam: a risk analysis. NeuroToxicology, 81, 382-386.

Bjørklund, G., Dadar, M., Chirumbolo, S., Aaseth, J., & Peana, M. (2020, 2020/08/01/). Metals, autoimmunity, and neuroendocrinology: Is there a connection? Environmental Research, 187, 109541.

Björkman, L., Lundekvam, B. F., Laegreid, T., Bertelsen, B. I., Morild, I., Lilleng, P., Lind, B., Palm, B., & Vahter, M. (2007, Oct 11). Mercury in human brain, blood, muscle and toenails in relation to exposure: an autopsy study. Environ Health, 6, 30.

Björkman, L., Musial, F., Alræk, T., Werner, E. L., & Hamre, H. J. (2022). Mercury, silver and selenium in serum before and after removal of amalgam restorations: results from a prospective cohort study in Norway. Acta Odontologica Scandinavica, 1-13.

Cabaña-Muñoz, M. E., Parmigiani-Izquierdo, J. M., Bravo-González, L. A., Kyung, H. M., & Merino, J. J. (2015). Increased Zn/Glutathione Levels and Higher Superoxide Dismutase-1 Activity as Biomarkers of Oxidative Stress in Women with Long-Term Dental Amalgam Fillings: Correlation between Mercury/Aluminium Levels (in Hair) and Antioxidant Systems in Plasma. PLoS One, 10(6), e0126339.

Chapman, L., & Chan, H. M. (2000, Mar). The influence of nutrition on methyl mercury intoxication. Environ Health Perspect, 108 Suppl 1(Suppl 1), 29-56.

Crowe, W., Allsopp, P. J., Watson, G. E., Magee, P. J., Strain, J. J., Armstrong, D. J., Ball, E., & McSorley, E. M. (2017, 2017/01/01/). Mercury as an environmental stimulus in the development of autoimmunity – A systematic review. Autoimmunity Reviews, 16(1), 72-80.

Ekstrand, J., Björkman, L., Sandborgh-Englund, G., & Edlund, C. (1998, 01 / 01 /). Toxicological aspects on the release and systemic uptake of mercury from dental amalgam [Article]. European Journal of Oral Sciences, 106(2), 678-686.

Ertaş, E., Aksoy, A., Turla, A., Karaarslan, E., Karaarslan, B., Aydın, A., & Eken, A. (2014). Human brain mercury levels related to exposure to amalgam fillings. Human & Experimental Toxicology, 33(8), 873-877.

Gul, N., Khan, S., Khan, A., Nawab, J., Shamshad, I., & Yu, X. (2016, 2016/10/01). Quantification of Hg excretion and distribution in biological samples of mercury-dental-amalgam users and its correlation with biological variables. Environmental Science and Pollution Research, 23(20), 20580-20590.

Guzzi, G., Grandi, M., Cattaneo, C., Calza, S., Minoia, C., Ronchi, A., Gatti, A., & Severi, G. (2006, Mar). Dental amalgam and mercury levels in autopsy tissues: food for thought. Am J Forensic Med Pathol, 27(1), 42-45.

Halbach, S., Kremers, L., Willruth, H., Mehl, A., Welzl, G., Wack, F. X., Hickel, R., & Greim, H. (1998, 1998/05/01/). Systemic Transfer of Mercury from Amalgam Fillings before and after Cessation of Emission. Environmental Research, 77(2), 115-123.

Jirau-Colón, H., González-Parrilla, L., Martinez-Jiménez, J., Adam, W., & Jiménez-Velez, B. (2019). Rethinking the Dental Amalgam Dilemma: An Integrated Toxicological Approach. International Journal of Environmental Research and Public Health, 16(6), 1036.

Keshavarz, M., Eslami, J., Abedi-Firouzjah, R., Mortazavi, S. A., Abbasi, S., & Mortazavi, G. (2022, Jun). How Do Different Physical Stressors’ Affect the Mercury Release from Dental Amalgam Fillings and Microleakage? A Systematic Review. J Biomed Phys Eng, 12(3), 227-236.

Khaled, E. M., Meguid, N. A., Bjørklund, G., Gouda, A., Bahary, M. H., Hashish, A., Sallam, N. M., Chirumbolo, S., & El-Bana, M. A. (2016, 2016/12/01). Altered urinary porphyrins and mercury exposure as biomarkers for autism severity in Egyptian children with autism spectrum disorder. Metabolic Brain Disease, 31(6), 1419-1426.

Kristoffersen, A. E., Alræk, T., Stub, T., Hamre, H. J., Björkman, L., & Musial, F. (2016). Health Complaints Attributed to Dental Amalgam: A Retrospective Survey Exploring Perceived Health Changes Related to Amalgam Removal. Open Dent J, 10, 739-751.

Lichtenberg, H. (1993 ). Elimination of symptoms by removal of dental amalgam from mercury poisoned patients, as compared with a control group of average patients. Journal of Orthomolecular Medicine, 8(3), 145-148.

Lindh, U., Hudecek, R., Danersund, A., Eriksson, S., & Lindvall, A. (2002, Oct-Dec). Removal of dental amalgam and other metal alloys supported by antioxidant therapy alleviates symptoms and improves quality of life in patients with amalgam-associated ill health. Neuro Endocrinol Lett, 23(5-6), 459-482.

Mehrandish, R., Rahimian, A., & Shahriary, A. (2019, 2019/3/15). Heavy metals detoxification: A review of herbal compounds for chelation therapy in heavy metals toxicity. J Herbmed Pharmacol, 8(2), 69-77.

Melchart, D., Vogt, S., Köhler, W., Streng, A., Weidenhammer, W., Kremers, L., Hickel, R., Felgenhauer, N., Zilker, T., Wühr, E., & Halbach, S. (2008, Apr). Treatment of health complaints attributed to amalgam. J Dent Res, 87(4), 349-353.

Merino, J. J., Parmigiani-Izquierdo, J. M., Toledano Gasca, A., & Cabaña-Muñoz, M. E. (2019, Apr 16). The Long-Term Algae Extract (Chlorella and Fucus sp) and Aminosulphurate Supplementation Modulate SOD-1 Activity and Decrease Heavy Metals (Hg(++), Sn) Levels in Patients with Long-Term Dental Titanium Implants and Amalgam Fillings Restorations. Antioxidants (Basel), 8(4).

Mortazavi, G., Haghani, M., Rastegarian, N., Zarei, S., & Mortazavi, S. M. (2016, Mar). Increased Release of Mercury from Dental Amalgam Fillings due to Maternal Exposure to Electromagnetic Fields as a Possible Mechanism for the High Rates of Autism in the Offspring: Introducing a Hypothesis. J Biomed Phys Eng, 6(1), 41-46.

Mutter, J. (2011, Jan 13). Is dental amalgam safe for humans? The opinion of the scientific committee of the European Commission. J Occup Med Toxicol, 6(1), 2.

Nylander, M., Friberg, L., & Lind, B. (1987). Mercury concentrations in the human brain and kidneys in relation to exposure from dental amalgam fillings. Swed Dent J, 11(5), 179-187.

Paknahad, M., Mortazavi, S. M., Shahidi, S., Mortazavi, G., & Haghani, M. (2016). Effect of radiofrequency radiation from Wi-Fi devices on mercury release from amalgam restorations. J Environ Health Sci Eng, 14, 12.

Prochazkova, J., Sterzl, I., Kucerova, H., Bartova, J., & Stejskal, V. D. (2004, Jun). The beneficial effect of amalgam replacement on health in patients with autoimmunity. Neuro Endocrinol Lett, 25(3), 211-218.

Rafiee, A., Delgado-Saborit, J. M., Aquilina, N. J., Amiri, H., & Hoseini, M. (2022, 2022/08/01). Assessing oxidative stress resulting from environmental exposure to metals (Oids) in a middle Eastern population. Environmental Geochemistry and Health, 44(8), 2649-2668.

Spiller, H. A., Hays, H. L., & Casavant, M. J. (2021, 2021/01/01). Rethinking treatment of mercury poisoning: the roles of selenium, acetylcysteine, and thiol chelators in the treatment of mercury poisoning: a narrative review. Toxicology Communications, 5(1), 19-59.

Sterzl, I., Hrda, P., Stejskal, V., Matucha, P., Prochazkova, J., & Bartova, J. (2006, 12 / 01 /). Removal of dental amalgam decreases anti-TPO and anti-Tg autoantibodies in patients with autoimmune thyroiditis [Article]. Neuroendocrinology Letters, 27(SUPPL. 1), 25-30.

Zwicker, J. D., Dutton, D. J., & Emery, J. C. (2014, Nov 18). Longitudinal analysis of the association between removal of dental amalgam, urine mercury and 14 self-reported health symptoms. Environ Health, 13, 95.