Affects of Mercury Toxicity

By Cat, Aug 2007; moved to Cat’s Kitchen, and updated April 2022

Mercury may well be the most problematic of the toxic heavy metals, because it is a ubiquitous environmental pollutant.  Mercury poses a unique problem because it is routinely used in medical and dental practices.  Silver fillings are made with mercury; vaccines are preserved with thimerosol, a compound of mercury. 

For more detail on mercury toxicity:  disorders associated with toxic mercury, and how one can be exposed to mercury, refer to Mercury Toxicity:  Disease and Exposure.

Affect on Metabolic Processes

Mercury is very toxic to the metabolic processes of the cells.  It binds to sulfur atoms (in sulfhydryl, or SH, groups) in important intracellular molecules, disabling the action of the bound compound. And it’s very hard to remove it from the cells, once it is there. Affected molecules include (not a complete list):

  • glutathione (the body’s primary antioxidant and detox agent, made in the liver);
  • cysteine (an amino acid, precursor to glutathione and other important compounds);
  • biotin (a B Vitamin);
  • lipoic acid (an antioxidant, and important in energy production at the cellular level);
  • coenzyme A (also important in energy production).

Mercury’s affinity for glutathione is especially troubling because it, along with the enzyme glutathione peroxidase, is the most important antioxidant defense in the human body, and especially in the liver, the primary organ for detoxification.  Mercury causes a marked reduction in glutathione production, resulting in a marked rise in oxidative stress within the affected organs, which in turn results in a marked increase in free radical generation. (4)   (Refer to my article on inflammation for more on the subject of oxidative stress and free radicals). < I’ve not yet moved the inflammation article from iweb: Health-Metabolism section

Mercury (as well as other toxic metals) also binds to other molecular subgroups in addition to the SH group, such as hydroxyl (OH), amine (NH2), and chlorine (Cl), in enzymes, coenzymes, and hormones, to disrupt many cellular processes and trigger allergic/immune response.  For example, mercury (8): 

  1. Impairs conversion of inactive thyroid T4 hormone to the active T3 form (hypothyroidism), and causes autoimmune thyroiditis in the affected persons.  
  2. Causes abnormalities in the hypothalamus-pituitary-adrenal (HPA) axis, resulting in inappropriate cytokine release, which can in turn result in several problems including hypocortisolism (low cortisol), fatigue, and the autoimmune disorders:
    • Lupus
    • Scleroderma
    • Rheumatoid Arthritis
    • Chronic Fatigue syndrome (CFS)
    • Fibromyalgia Syndrome (FMS)

Also, mercury has detrimental effect on mitochondrial membranes.  Mitochondria are cell-like components of cells that produce energy from sugars, fats and protein. 8  It is through this problem that mercury may be involved in insulin resistance.

Affect on Central Nervous System Function

Elemental mercury (especially mercury vapor, such as from dental fillings) easily and rapidly crosses the blood brain barrier.  This is because it is fat soluble, and the blood brain barrier is comprised of a very sophisticated layer of fats.  Mercury is then stored in the pituitary gland, hypothalamus and occipital cortex.  The hypothalamus is the gland that regulates the function of the endocrine system, including the thyroid and adrenal glands. The occipital cortex is involved in visual function.  The frontal lobe is involved in memory function; it is here that mercury may play a significant role in Alzheimer’s. 4,8

Mercury is highly toxic to the cells of the central nervous system  Heres a list of just some of the toxic effects it induces (some of these terms are highly technical, sorry about that): 8

  • lipid peroxidation (oxidation of the fatty acids that form the protective barrier of nerve tissue);
  • excess dopamine toxicity (dopamine is a neurotransmitter);
  • excess glutamate toxicity (glutamate is a neurotransmitter and in excess, is an excitotoxin); more on this below..

Mercury (and other toxic metals) inhibit the function of astrocytes in the brain.  Astrocytes are a type of cell that keep the area around the nerve cells clean, for proper nerve transmission to occur.  They neutralize excess glutamate, by transforming it to glutamic acid.  When glutamate is allowed to accumulate in the absence of astrocyte function, it continually excites the neurons, causing them to fire inappropriately, and eventually leads to nerve cell death. Excess glutamate has been shown to cause increased sensitivity to pain and higher body temperature seen in patients with Chronic Fatigue Syndrome and Fibromyalgia. 8

For an excellent video on the damage mercury can do to your brain and nerve tissue, watch a video from the University of Calgary (11) (also available on Dr. Mercola’s web site (1b)).

Affect on Immune and Detox System Function

Mercury is also highly toxic to the liver and immune system.  Heres a list of just some of the toxic effects it induces (some of these terms are highly technical, sorry about that) (8):*

  • reactive oxygen species (free radicals) and oxidative stress;
  • lipid peroxidation 
  • excess free cysteine levels (cysteine is a sulfur-containing amino acid);
  • inducement of  inflammatory cytokine TNFa (Tumor Necrosis Factor alpha)
  • reduced glutathione levels (glutathione is the primary antioxidant used by the liver for detox; this problem is discussed above)
  • liver enzyme effects (by binding to sulfur in the enzyme)
  • inhibition of protein kinase C and Cytochrome P450
  • nitric oxide and  peroxynitrite toxicity
  • excess free cysteine levels
  • autoimmunity

Human and animal studies confirm that mercury: (8)*

  • increases effects of herpes simples-2 virus
  • facilitates infestation by pathogens such as viruses, harmful bacteria (such as chlamydia), candida, mycoplasma, and parasites.

‘* 2022 update: if link (8) doesn’t work, check out the following articles:

  • Effects of Mercury on the Immune System (12)
  • Mercury and Fatty Liver Disease (13)
  • Effects of Mercury Exposure on Blood Chemistry and Liver (14)


  1. Mercola: (note his articles may have been removed from his site)
    1. (note his articles may have been removed from his site)
  4. 2022 WARNING: this site might by risky:
  8. < link may no longer be valid
  11. YouTube video:  (original link no longer valid:
  12. Effects of Mercury on the Immune System:
  13. Mercury and Fatty Liver Disease:
  14. Effects of Mercury Exposure on Blood Chemistry and Liver:


About Cat

See my 'About' page
This entry was posted in Uncategorized and tagged , , . Bookmark the permalink.