Credits: Hunter, W. 2017. Self Hacked Blog

Heavy Metal Toxicity - The signs and symptoms

Heavy metals are present in our environment, the foods we eat and in the cleaning agents we use. These metals wreak havoc on the body, interfere with our ability to detox and generate a myriad of emotional and physical dis-eases. In this article, we will explore how these symptoms present themselves and what you can do about it (Part 2).

According to Hunter (2017), heavy metals are metals or metalloids (having properties of metals and nonmetals) that have a density of at least 5 g/cm3 and adversely affect the environment and living organisms if present in large of quantities.

Heavy metals are everywhere and originate from both natural and human sources, such as volcanic eruption, or coal burning and gold mining. In recent years, the amount of metals in the environment has increased significantly, necessitating strategies to mitigate the harm caused by them as well as to remove them from the body.

A few examples of heavy metals include:

  • Arsenic
  • Mercury
  • Cadmium
  • Lead

Other metals that are vitally important to health in small quantities, however, may become toxic in excess: 

  • Iron
  • Zinc
  • Copper
  • Magnesium
  • Chromium
  • Manganese


Arsenic and cadmium are classified as carcinogens (causes cancer). Other possible carcinogens are lead and mercury.

One large observational study amongst 1578 healthy women found high levels of lead and cadmium in the placenta, which may affect the growth and development of the fetus. Lead was found in all cord blood and 96% of placental tissue, while cadmium was found in 95% of cord and 98% of maternal blood samples.

Heavy metals have been shown to bind proteins, prevent their functioning and disrupt cellular function by interfering with necessary minerals like zinc and magnesium and causing oxidative stress.

Symptoms of heavy metal intoxication include:

  • Intellectual disability in children
  • Dementia
  • Kidney and liver diseases
  • Insomnia, emotional instability
  • Depression
  • Vision abnormalities



Mercury is considered to be the most toxic heavy metal in the environment.
The majority of exposure to mercury is due to seafood, with additional sources including occupational exposure such as small-scale gold mining and dental amalgam installation and removal. Mercury is passed on from mother to child during pregnancy too, so although you may not have amalgams, if your mother does (and got them before she fell pregnant), chances are you have mercury toxicity to some degree.

Mercury accumulates in organisms as you go up the food chain, meaning larger fish such as tuna, shark, and swordfish have proportionally more mercury than smaller fish like sardines, mackerel, and anchovies.

Because it’s attracted to fat (lipophilic), the metal accumulates in the fat and liver of fish, and when consumed by humans it accrues in the brain and nerves (specifically the myelin sheaths of nerves, which are made of fats). The brain, kidneys, and liver are the major storage sites for mercury accumulation.

Mercury poisoning can cause:

  • Depression
  • Memory problems
  • Fatigue, headache
  • Hypertension
  • Hair loss
  • Permanent brain damage
  • Kidney damage
  • Loss of balance and coordination

Chronic mercury exposure is associated with:

  • Heart attacks
  • Arterial dysfunction
  • Atherosclerosis
  • Alzheimer’s Disease

Higher mercury levels were found in the brain and blood of Alzheimer’s patients. In animals, low levels of mercury are able to cause cell deterioration similar to what is seen in Alzheimer’s disease.

Moreover, mercury levels range from 2-10 times higher in individuals with dental amalgams, and women with dental amalgams had a 13% increased risk for Alzheimer’s disease compared to women without them.


Chronic exposure to arsenic causes a variety of symptoms and health conditions.
Foods grown in contaminated soil and water are the main sources of intake for most people.

In recent years, there were scandals where high levels of arsenic were found in rice and apple juice. It’s recommended that babies don’t drink rice-based drinks because of this.

The primary targets for arsenic and compounds containing arsenic are the kidneys and the liver, because they are generally processed by the liver and excreted in the urine. Excessive exposure during childhood can lead to behavioural dysfunction during puberty even lasting into adulthood.

Arsenic exposure has also been associated with:

  • Deficits in verbal intelligence long-term memory in children
  • Diabetes
  • Increased fetal mortality and preterm birth

Long-term exposure can cause:

  • Inflammation of the nerves, causing pain and loss of function
  • Skin lesions, darkening of the skin (hyperpigmentation)
  • Internal cancers including bladder, kidney, liver prostate, and lung
  • High blood pressure
  • Increased risk of mortality
  • Toxic effects on genes, which can cause mutations


Up until recent years, lead was often used in paints, ceramics, and pipes. Although its use in these products has been significantly reduced, a report found that 25% of homes in the US have significant amounts of lead-contaminated paint, dust, or soil.

The majority of lead poisoning cases in adults are due to occupational exposure, such as inhaling lead-contaminated dust, while lead exposure in the general population is mainly through processed food and beauty products.
Lead can accumulate in the kidneys, liver, heart, brain, and especially in the bones.

Symptoms of lead exposure on the brain include:

  • Headaches
  • Poor attention span
  • Irritability
  • Memory Loss

Lead exposure is of particular concern in pregnant women, as it easily crosses the placental barrier and enters the developing fetus. Both human and animal studies show that lead exposure during pregnancy is associated with reduced birth weight and preterm delivery, as well as cognitive deficits in the offspring.


Cadmium is a relatively highly water-soluble metal. In smokers, tobacco is the main source of cadmium because tobacco plants tend to accumulate the metal from the soil.

For non-smokers, the main source is through diet and occupational exposure, including metal industries, soldering, battery manufacturing, and cadmium-contaminated workplaces. Cadmium is highly toxic to the kidneys and preferentially accumulates in a specific type of cell (proximal tubular cells).

Long-term exposure can cause:

  • Kidney disease
  • Osteoporosis
  • Disrupted calcium metabolism
  • Kidney stones

Heavy Metal Toxicity Symptoms


Physicians often test for heavy metals using urine, whole blood, red blood cell, and less commonly, hair, or rarely, toenail samples.

  • Blood Tests for Heavy Metals
    In most cases blood testing is indicative of acute exposure rather than the total body burden (total amount of heavy metals accrued over one’s lifetime that is present in the body), however, there are exceptions.
  • Hair Testing for Heavy Metals
    If done correctly, hair analysis is the most reliable way to see if you have heavy metal toxicity. Hair testing mainly reflects past exposure, so it should be combined with urine or blood testing to confirm heavy metal toxicity.

Personally, I find looking at the symptoms is a pretty reliable way of determining whether you need a heavy metal detox. The reality is that most of us have some degree of heavy metal toxicity.