Heavy metals are so ubiquitous in the environment that nowadays it has become almost impossible to avoid exposure to them in everyday life. You are exposed to heavy metals from myriad sources: for example, through inhaling air pollutants and consuming contaminated drinking water and foods, or being exposed to contaminated soils or industrial waste. Food sources such as grains, vegetables, fruits, fish and shellfish can easily become contaminated by accumulating metals from the surrounding soil and water.
Many toxic heavy metals are associated with particulate matter emitted from industrial and domestic sources, which are then inhaled. This includes the particulate matter from fossil-fuel combustion, mining, industrial chemical manufacturing, oil and gas extraction, petroleum refining and motor vehicle exhausts (including diesel), to name just a few. These particles are respirable and able to be transported over very long distances.
Chronic, low-level exposure to toxic metals is an increasing problem worldwide. The symptoms associated with the slow accumulation of toxic heavy metals are multiple and nondescript, yet they affect a vast array of biochemical processes with overt symptoms often not appearing until later in life. Since symptoms of chronic exposure often develop slowly over months or years, heavy-metal toxicity is often overlooked. Heavy-metal accumulation may be the underlying cause of persistent ill-health, particularly if associated with chronic symptoms of fatigue, musculoskeletal pain, neurological disorders, depression, poor cognitive function, poor memory and allergic hypersensitivity.
Chronic heavy metal exposure can result in serious health effects, including reduced growth and development, cancer, organ damage and nervous system damage. Exposure to certain metals, such as mercury and lead, can also be a potential factor in the development of autoimmune diseases. Heavy-metal burden can cause impairment to every system in your body as well as weaken your detoxification processes, energy-production processes and enzyme pathways.
Hair mineral analysis is useful to screen for the initial detection of heavy-metal exposure, but because heavy metals are often stored in your organs and tissues they are not always freely available to be picked up in hair mineral-analysis tests. Results, therefore, may not accurately reflect your current heavy-metal status. Urine and blood tests can also screen for the presence of heavy metals.
Mercury is the most toxic non-radioactive element because it has a higher propensity to bond with protein components in your body, which causes their irreversible inhibition and prevents them from carrying out their functions. Sources of mercury exposure include mercury vapour from dental amalgams, contaminated water, food sources such as seafood, and occupational exposures from dental offices, fluorescent lamp factories and mercury mining.
Most people are exposed to mercury via food. There are various forms of mercury, including methylmercury, elemental mercury and other inorganic and organic mercury compounds. Methylmercury is found in fish that have been exposed to the metal from streams and oceans as they feed. Large, predatory fish that are at the top of the food chain therefore tend to contain higher levels of mercury than smaller fish. Fish that contain higher levels of mercury include shark (flake), swordfish, barramundi, gemfish, orange roughy, ling and southern bluefin tuna. Methylmercury usually accumulates in fish through the food chain, but consumption of farmed fish can also lead to methylmercury exposure due to the presence of methylmercury in feed.
Other foods that have been cultivated in areas contaminated with mercury can contain relatively high levels of methylmercury. Rice, for example, is a common source of mercury contamination due to the large quantities of water required for its cultivation. Methylmercury has also been reported in organ meats, chicken and pork, most likely due to the use of fishmeal as livestock feed.
Health effects of mercury exposure include brain and central nervous system damage and kidney damage, with children and foetuses whose brains are still developing most at risk.
In June 2003, a review was carried out by the Joint Food and Agricultural Organisation (FAO) and the World Health Organization (WHO) Expert Committee on Food Additives on the effects of prenatal mercury exposure. As a result of this review, the researchers recommended reducing the amount of fish known to contain mercury in the diet, particularly for pregnant women. The Australian guidelines for safe levels of mercury in the diet currently reflect the Joint FAO and WHO Expert Committee on Food Additives research.
Health effects of prenatal mercury exposure
- Vision, speech and hearing impairments
- Auditory function and auditory processing impairments
- Visual/motor integration
- Learning disabilities
- Impaired learning and memory
Mercury, in the form of elemental mercury, is used in dental amalgams for the treatment of dental caries. Mercury comprises about 50 per cent of amalgams. Every time you chew your food, mercury vapours are released from your amalgam fillings into your oral cavity. The mercury from dental amalgams is easily vaporised from the mouth and absorbed into the bloodstream via the lungs. Once absorbed, mercury has a low excretion rate. Mercury is known to significantly accumulate in the kidneys as well as in neurological tissue and the liver.
A study published in Human and Experimental Toxicology in April 2013 found that amalgams contribute to ongoing damage to the proximal tubules of the kidneys. Autopsy studies carried out on dentists occupationally exposed to mercury through the use of dental amalgams also found high levels of mercury in cardiac, thyroid and pituitary tissues.
Various studies have confirmed that the average daily exposure to mercury vapour in people with amalgam fillings is well above the Health Standard for mercury vapour established by the US Agency for Toxic Substances and Disease Registry (ATSDR). In 1997, a large study was undertaken in which the level of mercury in saliva of 20,000 individuals with amalgam fillings was measured. The average amount of daily total exposure to mercury was above 10 micrograms a day, which is more than two-and-a-half times the Health Standard for mercury vapour established by the ATSDR.
Mercury-containing vaccine preservatives
Thiomersal is a mercury-based preservative used in some vaccines. The type of mercury found in thiomersal is known as ethylmercury. In 2000, Australia removed thiomersal from most childhood vaccines as a precautionary measure due to the mercury content, but it’s still found in one type of hepatitis B vaccine. Other vaccines in Australia that contain thiomersal include the Japanese encephalitis and Q fever vaccines.
Ethylmercury does not accumulate in the body to the same extent as methylmercury due to its shorter half life of only about seven to 10 days. Despite this lower level of bioaccumulation it has been suggested that ethylmercury exposure may cause neurological problems and autism in children who have been injected with thiomersal-containing vaccines. While some investigations have shown a link between these vaccines and the development of autism, other studies have not demonstrated the same correlation.
Sources of mercury exposure
- Food crops cultivated with mercury-contaminated water
- Meat from livestock fed mercury-contaminated feed
- Dental amalgams
- Vaccines containing thiomersal
- Old acrylic (latex) paint
- Contact-lens solutions containing thiomersal
- Fluorescent light bulbs
- Skin-lightening creams
- Mercury thermometers
- Switches and relays in electrical goods
- Fossil fuels
Animal studies have shown that mercury accumulation can result in brain lesions that closely resemble those found in patients with Alzheimer’s disease. Research has also revealed that individuals with Alzheimer’s disease can have elevated levels of mercury in brain tissue, with an average mercury load of 20–178 micrograms of mercury per gram.
In 2010, a systematic review published in the Journal of Alzheimer’s Disease found that inorganic mercury is significantly associated with the pathogenesis of Alzheimer’s disease and recommended that the industrial and medical use of mercury should be eliminated as soon as possible as a primary public health preventive measure.
Constant low-dose mercury exposure — from dental amalgams, for example — has been considered a possible cause of certain autoimmune diseases, including multiple sclerosis (MS), rheumatoid arthritis and systemic lupus erythematosus. Animal studies have shown that methylmercury and inorganic mercury both suppress immune functions and produce an autoimmune response. Exposure to inorganic mercury may also cause a loss of Schwann cells, which are components of the myelin sheaths and implicated in the development of MS. Mercury levels have been found to be seven-and-a-half times higher in the cerebrospinal fluid of individuals with MS.
Mercury inhibits the production of haem, which plays several important roles in the body. Haem is a component of haemoglobin, which is responsible for transporting oxygen around the body. It is also an important cofactor for the P450 class of enzymes that are responsible for detoxification, while also being a necessary cofactor required for cellular energy production. It’s due to these many roles that mercury inhibition of haem is thought to cause a multitude of health effects, including anaemia, fatigue and increased oxidative stress throughout your body.
Mercury and cadmium are both able to inhibit the conversion of thyroid hormone thyroxine (T4) to triiodothyroxine (T3). Mercury irreversibly binds to selenium resources, which are required for the conversion of T4 into T3. These mercury-induced disruptions to thyroid hormone metabolism can also contribute to chronic fatigue, one of the features of mercury burden.
Mercury is also able to disrupt progesterone metabolism by binding to the progesterone receptor, a protein found inside cells. Mercury thereby decreases progesterone binding and cellular response to progesterone, resulting in an imbalance between your oestrogen and progesterone levels and putting you at an increased risk of oestrogen-dominant disorders.
Hypertension and myocardial infarction — significant mercury accumulation has been found in heart tissues with a form of heart insufficiency.
Research published in 2008 in Mutation Research demonstrated that dental amalgam fillings caused DNA damage in human blood cells, a carcinogenic effect. Significantly elevated mercury levels have also been observed in breast cancer tissues.
Your metabolism of minerals is also affected by toxic metal burden. Mercury and cadmium both displace zinc and copper, which are required for the antioxidant enzyme superoxide dismutase. Copper in trace amounts is also required by the body for neurotransmitter synthesis. Zinc is important for wound healing and has many immune functions in your body. Mercury can also cause selenium and magnesium deficiencies. This not only contributes to mineral-deficiency-related disorders but also further diminishes your detoxification capacity.
Health effects of mercury exposure
- Chronic fatigue
- Muscle and joint pain
- Poor memory and cognitive function
- Compromised immune function
- Digestive disorders
- Sleep disorders
- Mood disorders
- Peripheral numbness or tingling
- Decreased senses of touch, hearing or vision
- Cardiovascular disease
- Oestrogen-dominant disorders such as uterine fibroids, endometrial polyps
- Thyroid/pituitary dysfunction
- Hypersensitivity reactions
Lead enters the body via inhalation or ingestion. Lead may be inhaled as a fume when it is burned or melted, or when dust that contains lead becomes airborne — for example, when dry leaded paint is being removed from a surface. Children may ingest lead if they play in contaminated soil. Cigarettes, food or food-preparation surfaces contaminated by dust containing lead are other sources of exposure.
Lead that is not excreted from the body and is absorbed into tissues is distributed primarily in bones and teeth, which typically contain the vast majority of the lead body burden. The bones and teeth of adults contain more than 95 per cent of the total lead body burden, while in children they contain about 73 per cent. Blood and soft tissues such as the liver, kidneys, lungs, brain, spleen, muscles and heart are also sites of lead accumulation. In times of stress, particularly during pregnancy and lactation, the body mobilises lead stores, thereby increasing blood levels of lead. The body accumulates lead over a lifetime and eliminates it very slowly.
Sources of lead exposure
- Before 1950, lead-based paint was used on the inside and outside of most homes.
- Soil near heavily used streets and roads may contain lead as a result of past use of lead in petrol, and when located near homes painted with lead-based paints.
- Drinking water is exposed to lead as a result of corrosion of plumbing materials containing lead, such as lead-based solder, lead pipes or brass and chrome-plated faucets. Water that has sat in lead-soldered pipes for longer than six hours should not be consumed.
- Lead contained in the glazes on ceramic cookware can leach out and enter food during the cooking process.
- Lead solder is still used in some countries to seal cans used in food canning. Acidic foods and drinks such as pickles or fruit juice enhance the leaching process.
- Certain cosmetics, eg kohl eyeliners
- Old toys
- Lead-glazed or lead-painted pottery
- Lead crystal
- Leaded petrol
- Industrial processes such as lead smelting, coal combustion
Living in or renovating an older home increases your risk of lead exposure as older homes often retain remnants of lead-based paint. Other risk factors include hobbies such as stained-glass making, which requires the use of lead solder, and your country of origin. If you live in a developing country you are at higher risk of lead poisoning, since the regulations in these countries tend to be less rigorous.
Lead exposure is commonly higher in infants and younger children compared to older children and adults, due to chewing on lead-based toys or paint chips from lead-based paint. Young children also absorb lead more easily and sustain more harm from it. The WHO states that childhood lead exposure is estimated to contribute to about 600,000 new cases of children developing intellectual disabilities every year.
Health effects of lead exposure
Lead toxicity primarily affects your central nervous system, hepatic system, renal system and haematopoietic system (blood), and produces serious disorders at high levels of toxicity. Lead toxicity can cause a range of symptoms with the degree of damage being dependent on the amount of lead accumulation in your body over time.
Low levels of lead exposure are associated with anaemia, headaches, general weakness, fatigue, learning disabilities, joint pain, muscle aches, nervousness, irritability, impotence, insomnia, decreased fertility, miscarriage, impaired development of the nervous system, and slowed movement of nerve impulses. Signs to look for in children include irritability, apathy, loss of appetite, abdominal pain, clumsiness, behavioural problems, learning disabilities and constipation. Lead toxicity as a cause of these symptoms is easily overlooked as they mimic several other paediatric disorders.
High levels of lead exposure can include symptoms such as vomiting, abdominal pain, kidney damage, immune-system damage, short-term memory loss and decreased visual-motor co-ordination. Advanced cases of nervous system damage can manifest in “wrist drop” or “foot drop”, the inability to maintain the hand or foot in a normal position due to weakness of muscle tone because of nerve damage. If blood levels become excessive, seizures, impaired muscular co-ordination, erratic behaviour, blue colouration to the gums and skin under fingernails, and even coma or death can occur.
As with mercury accumulation, lead toxicity also causes anaemia by impairing the ability to synthesise haem. Furthermore, lead toxicity also renders the red blood cell extremely vulnerable to oxidative stress, which increases the fragility of cell membranes and leads to cell death.
Renal damage occurs most often at high levels of lead exposure, though damage at lower levels has also been reported. Kidney abnormalities following lead exposure potentially lead to irreversible kidney breakdown. In cases of long-term high exposures to lead in childhood, those children may show kidney disease later in life as adults.
Research has showed that low-level lead exposure contributes to hypertension, ischaemic heart disease, stroke and peripheral vascular disease.
Reproductive system effects
Lead causes many reproductive and fertility health problems in both women and men, including reduced libido, reduced motility and number of sperm, abnormal prostate function, miscarriage, pre-eclampsia and premature delivery
Nervous system effects
Lead’s ability to cross the blood–brain barrier and its accumulation in brain cells cause various neurological and nervous system effects. The toxic effects of lead are greater in developing nervous systems and therefore particularly harmful to the developing brains of foetuses and young children. Lead also affects crucial neurotransmitters involved in regulating memory storage.
Lead toxicity causes significant effects on essential cellular processes.
Common symptoms associated with lead toxicity
- Loss of appetite
- Poor memory
- Poor concentration
- Behavioural disorders
- Decreased co-ordination
- Abdominal pain
- Bone and muscle pain
Minimising lead exposure
- Never sand, burn or heat a surface that you suspect contains lead-based paint.
- Repaint surfaces where lead-bearing paint is cracking, chipping or peeling.
- Prevent children from using lead-based toys and other objects that may contain lead.
- Ensure adequate iron and calcium intakes to help decrease the amount of lead absorbed into the body.
- Don’t wear lead-contaminated clothing home from the workplace.
- Use filtered water for drinking.
Aluminium is difficult to avoid in everyday life as it is used widely in cooking utensils, pharmacological medications such as antacids and consumer products such as antiperspirants and deodorants.
Aluminium inhibits more than 200 biologically important functions, and causes various adverse health effects, particularly of the central nervous system. Aluminium accumulates in lung, bone and brain tissue. High exposure to aluminium can cause problems with your kidneys, muscles, bones and digestive system.
Health effects of aluminium toxicity
- Neurodegenerative diseases
- Impairment to brain development
- Apoptic death of nervous system cells — neurons and glial cells
- Impairment of various enzymes, including those related to neurotransmitter synthesis
- Spatial memory deficit (the part of memory related to recording information about your environment, for example, that is required for navigating around a familiar neighbourhood)
- Influence on emotional reactivity
- Impairment to various brain functions related to learning and memory
The hypothesis that aluminium contributes to the pathogenesis of Alzheimer’s disease was first proposed in the 1960s based on various findings from neurotoxicological, analytical and epidemiological studies, with more recent research confirming the role of aluminium in Alzheimer’s disease.
Pathological features of Alzheimer’s disease include the deposition of extracellular senile plaques and intercellular neurofibrillary tangles in the brain. In 2009, a study published in the Journal of Inorganic Biochemistry found that aluminium was located in the senile plaques in the brains of patients with Alzheimer’s disease. Aluminium has also been discovered in the neurofibrillary tangles.
In 2011, the Journal of Alzheimer’s Disease reported that very small amounts of aluminium are needed to produce neurotoxicity and this amount is often ingested through dietary aluminium intake. Aluminium is able to cross brain barriers, with exposure to small amounts of aluminium over a lifetime promoting its accumulation in brain tissues.
Aluminium is also thought to be a factor in other neurodegenerative diseases, such as amylotrophic lateral sclerosis (ALS) and Parkinson’s disease.
Minimising aluminium exposure
- Aluminium cans that hold carbonated softdrinks are coated in a protective polymer, but if the can is dented or damaged, aluminium can leach into the drink. The same applies for aluminium water bottles. Avoid beverages in aluminium cans and opt for stainless-steel water bottles.
- Avoid aluminium cookware and use cast-iron or glass cookware instead. Use wax paper instead of aluminium foil for baking.
- Some baking powders are made with aluminium in the form of sodium aluminium sulphate. Check your baking powder is aluminium-free before use.
- Avoid antiperspirants and deodorants that contain aluminium.
- Avoid antacids containing aluminium.
In trace amounts, copper is necessary in the body. It’s used to help produce cellular energy and is involved in nerve conduction, connective tissue, the cardiovascular system and the immune system. For its role in cellular energy production, copper must be bound to special binding proteins — ceruloplasmin and metallothionine — in order to enter the cells. If these two proteins are lacking due to poor liver function, then unbound copper will accumulate in the blood and then begin to build up in all soft tissues of the body.
If you are not occupationally exposed to copper, the major route of exposure is oral. Drinking water can contribute substantially to your total daily intake of copper. High copper may occur naturally in water supplies, but more commonly it is introduced into the water supply via old copper plumbing. Vegetarians are also more likely to be exposed to high copper levels, since vegetarian diets contain up to five times the amount of copper than non-vegetarian diets. Nutritional deficiencies in zinc, manganese and other trace minerals can also contribute to copper toxicity due to the role they play in preventing excess copper accumulation.
Excessive oestrogen levels due to endocrine dysfunction or the use of the oral contraceptive pill is a risk factor for excess copper accumulation, due to the role of oestrogen in increasing copper retention in the kidneys. External sources of chemicals that mimic oestrogen when in the body, known as xenoestrogens, also increase the retention of copper. Sources of xenoestrogens include pesticides, plastic bags, volatile organic compounds, growth hormones in animal meats and petrochemical waste products.
Animal studies have demonstrated that copper accumulation contributes to inflammation of the liver and degeneration of the kidney tubule epithelium, testicular degeneration, reduced neonatal body and organ weights, immune function impairment, neurochemical changes and, at high doses, foetal malformations.
Copper also increases the production of adrenalin, noradrenalin and dopamine and decreases histamine production. Symptoms arising from the effect of copper on these neurotransmitters can include mood swings, depression, mental agitation, anxiety and insomnia.
Copper excess conditions
- Attention deficit disorder
- Candida overgrowth
- Male infertility
- Chronic infections
Factors contributing to copper excess
- Hormonal disturbances
- Adrenal gland insufficiency or exhaustion
- Zinc deficiency
- Vegetarian diets
- Occupational exposure
- Copper interuterine devices
- Oestrogen oral contraceptive pill
- Primary biliary cirrhosis
- Vitamin deficiencies
- Liver disturbances
- Hormone therapy
Arsenic toxicity arises mainly from contaminated drinking water in industrialising countries and affects millions of people worldwide. Chronic arsenic toxicity produces a variety of symptoms ranging from hyperpigmentation of the skin through to cancer of the skin and various internal organs. The pigmentation of chronic arsenic toxicity usually presents as a finely freckled “raindrop” pattern of pigmentation or depigmentation that is pronounced on the trunk and extremities. Pigmentation may sometimes be blotchy and involve mucus membranes such as the undersurface of the tongue. Chronic arsenic toxicity leads to irreversible damage in several vital organs.
Common symptoms of arsenic toxicity
- Muscle weakness
- Increased salivation
- Strong “garlic” breath
Cadmium, like mercury, accumulates heavily in the kidneys. The biological half life of cadmium in the kidneys is extremely lengthy, hence it will take many decades for your body to excrete the metal. Unlike mercury, cadmium does not cross the blood–brain barrier and is therefore more strongly associated with peripheral neuropathy than central nervous system disorders.
Cadmium toxicity can result in zinc deficiency as it replaces zinc in various important enzyme systems, impairing the functioning of these enzyme systems and consequently resulting in a wide range of health effects.
In 1998, a study published in the British Journal of Ophthalmology found that copper, lead and cadmium are all involved in the development of cataracts. Copper, lead and cadmium concentrations were measured in 37 lenses with cataracts and nine normal human lenses. It was found that the accumulation of copper, lead and cadmium all occurred in cataracts.
Common sources of cadmium include cigarette smoke, car fumes and pigment in oil paint. Cadmium is used in fungicides and for many industrial uses, including as a component of copper alloys and as a coating for iron, copper and steel and in many other industrial products.
Common symptoms of cadmium toxicity
- Kidney damage
- Decreased fertility
Detoxification of heavy metals
Detoxification of heavy metals depends on specific proteins and enzymes that bind the metals and transport them out of your cells into the bloodstream. All chelating agents, whether synthetic or natural, form chemical bonds with metal ions, rendering them much less chemically reactive. The resulting complex is water-soluble, which allows it to enter the bloodstream and, if your detoxification organs such as the liver, kidneys and gut are functioning well, these complexes are then removed from your body via urine and stools.
The most common synthetic heavy metal chelators are EDTA, DMPS and DMSA. In cases of acute metal poisoning, these chelators can potentially be life-saving. They bind to heavy metals in the body and they all have a very rapid mobilising activity. While they eliminate metals from your body quickly, they also place a huge burden on your detoxification systems. Metals enter the bloodstream rapidly, which can overwhelm the organs of excretion such as the liver and kidneys. Consequently, instead of being properly excreted, they may be redistributed and reabsorbed by vital organs, potentially damaging these organs further and rendering you in a worse state of health. Heavy metal chelators also bind to and remove beneficial minerals such as zinc, copper, manganese, iron, selenium and magnesium.
DMPS is available in intravenous and oral forms and was developed in the former Soviet Union as a mercury chelating agent. It’s not approved by the US Food and Drug Administration, which classifies it as an experimental agent. DMPS is primarily used for the treatment of arsenic and mercury poisoning.
DMSA is a pharmaceutical chelator, which is the US standard treatment of lead, arsenic and mercury poisoning. DMSA is unable to cross the blood–brain barrier, thus it has limited use in the treatment of the central nervous system. It also has low efficacy in removing lead from inside cells. Side-effects may include major brain fog, memory problems during detoxification, and depression due to redistribution of metals. In patients with chronic lead intoxication, haemolytic anaemia has been observed, with a return to normal blood values after termination of treatment. In children, it has also caused seizure disorders.
EDTA is primarily used for the chelation of lead. It’s usually administered intravenously over about one-and-a-half to three hours. Anywhere between five and 30 sessions may be required. EDTA produces substantial loss of essential minerals, including zinc, with plasma zinc levels decreasing by up to 30–40 per cent. It’s only able to chelate extracellular lead and not the lead from inside your cells. Side-effects may include dizziness, headache, mild nausea or irritation at the IV site. The most adverse effect from EDTA is the redistribution of lead to the brain. EDTA can also cause kidney toxicity.
Natural chelators & detoxification agents
When chelating heavy metals from your body, they need to be mobilised and eliminated very gently so your body reabsorbs less and you are not flooded with toxic metals that cause further damage to your vital organs. There are many natural chelating nutrients and herbs that help to reduce your metal burden. However, even some of these can be strong chelating agents and need to be used with caution and under the supervision of a health practitioner.
Mineral deficiency allows heavy metals to attach to specific binding sites in your body’s tissues. If you have a healthy mineral base, it can help prevent these attachments and heavy metal accumulation in vital organs. Electrolytes such as sodium, potassium, calcium and magnesium are also important in helping to transport toxic waste across the extracellular space towards the lymphatic and venous vessels.
Glutathione is produced naturally in the body, has many antioxidant functions and is a significant factor in heavy metal mobilisation and excretion, particularly mercury, cadmium and arsenic. If you have impaired production of glutathione you are more susceptible to heavy metal accumulation since one of the ways in which they leave your body is by being bound to glutathione and eliminated via the faeces or urine. A high level of glutathione is therefore needed to effectively eliminate heavy metals from the body.
L-cysteine/N-acetyl cysteine (NAC)
Cysteine is a sulphur-containing amino acid that chelates heavy metals and acts as a free-radical scavenger, thereby promoting detoxification. It is converted in the body into metabolites capable of stimulating glutathione synthesis and is also a key nutrient to support the production of metallothionein, a protein in the body responsible for “scavenging” certain heavy metals that enter the cells. Studies have shown that cysteine also protects against liver and kidney damage.
It’s imperative that you talk to your health practitioner before supplementing with L-cysteine or NAC as animal studies have shown that supplementation at high doses can actually increase the transport of mercury into the brain and exacerbate adverse neurological effects.
Chlorella has many mechanisms by which it is able to bind to metals. It is effective at removing toxic metals from the gut and transporting them out of the body. Chlorella binds all known toxic metals and increases glutathione.
Animal studies have shown that chlorella intake suppresses methylmercury transfer to the foetus during pregnancy, as well as suppressing methylmercury accumulation in the brain tissue of mothers. Pregnant mice were fed diets containing 10 per cent of chlorella powder, or a diet without chlorella powder, along with methylmercury in their drinking water. The blood and brain mercury levels of neonates and mothers in the chlorella-powder-diet group were significantly lower.
Coriander is a strong chelator that’s effective in mobilising mercury, cadmium, lead and aluminium stored in both bones and the central nervous system, including the brain. A recent animal study showed that rapid removal of aluminium and lead from the brain and skeleton by coriander was superior to any other known detoxification agent.
If your eliminatory systems are poorly functioning, coriander may mobilise more toxins than it can transport out of the body, resulting in heavy metal retoxification and further organ damage. It’s advisable to consult with your health practitioner about ways to reduce this risk, for example, by optimising your bowel function, consuming a high-fibre diet and simultaneously administering an intestinal toxin-absorbing agent such as chlorella.
Alpha lipoic acid (ALA)
Alpha lipoic acid is a sulphur-containing antioxidant synthesised in small amounts in the body. It regenerates other antioxidants, such as vitamin C and E, and increases cellular glutathione levels. Alpha lipoic acid binds with metals such as copper, mercury, lead and cadmium. Studies have demonstrated that it’s more effective at removing lead from brain tissues than other organs such as the liver, kidneys and other soft tissues. In 2010, research published in the Journal of American Science demonstrated that alpha lipoic acid reduces copper and lead levels in blood and tissues of the body and is able to minimise the toxic effects of both of these metals.
Other chelating nutrients
- Vitamin B6 (pyridoxine). Stimulates the production of glutathione. Moderate chelator.
- Vitamin B1 (thiamine). Protects against short-term implications of lead poisoning and lead-induced damage to liver and kidneys.
- Ascorbic acid (vitamin C). Animal studies have shown it protects against DNA damage and cell death of liver cells caused by lead. Prevents lead-induced oxidative stress. Regulates copper levels and removes excess copper.
- Vitamin E (alpha-tocopherol). Protects against free-radical damage to the cell membrane.
- Flavonoids. Naturally occurring constituents of fruits and vegetables. Antioxidants that chelate heavy metals and prevent free-radical generation.
- Quercetin. A bioflavonoid found in fruits, vegetables and tea.
Garlic & other sulphur-rich foods
Garlic and other foods rich in sulphur bind to mercury, cadmium and lead and reduce the heavy-metal burden in soft tissues such as the liver and kidney, as well as from blood and bone. They support glutathione production, protect against liver damage caused by lead-induced oxidative stress and protect blood cells from oxidative damage caused by metals in the bloodstream.
A constituent of turmeric, curcumin is an antioxidant and metal chelator that chelates lead from brain tissues and protects against lead-induced neurotoxicity.
Centella asiatica (gotu kola)
A heavy-metal chelator that ameliorates lead-induced oxidative stress, gotu kola is able to cross the blood–brain barrier and restore altered neurotransmitters and the impaired antioxidant balance caused by lead exposure.
Selenium has many antioxidant functions and helps recycle and produce more glutathione.
EPA and DHA found in fish oil induce the formation of peroxisomes in your cells and replace the damaged ones. It is at this level of the cell that toxic metals attach and thereby prevent the cell from functioning properly.
Improve toxin elimination
- Have one to two bowel movements a day.
- Drink at least eight glasses of water a day.
- Exercise regularly and improve your lymph flow through yoga or lymphatic massage to help flush toxins out of your tissues into your circulation for detoxification.
- Increase your fibre intake: eat more beans, whole grains, vegetables, fruits, nuts and seeds to enhance bowel elimination.
- Eat celery to increase urine flow and aid detoxification.
- Consume rosemary, which contains carnosol, to help boost detoxification enzymes.
- Consume chlorophyll to help cleanse the blood.
If you have a known body burden of heavy metals, a metal detoxification process should be undertaken only under the guidance of a qualified practitioner who can help support all systems of your body while the heavy metals are being mobilised and excreted in order to prevent re-toxification, exacerbation of your symptoms and damage to the organs to which the metals are redistributed.
Saskia Brown is a naturopath, nutritionist and health writer. W: saskiabrown.com