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Heavy Metal Toxicity and Hypothyroidism

Learn the link between heavy metal toxicity and the impact on your thyroid health.
 Heavy Metal Toxicity and Hypothyroidism
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Understanding metals and their role

Heavy metals are naturally occurring elements that are often applied to industrial, domestic, agricultural, medical, and technological uses. Because of their wide presence in our daily environment, there are multiple concerns raised about their potential effects on human health. Though these metals are naturally occurring, meaning found on the Earth, potential environmentally harmful activities such as nuclear power generation, wood preservation, paper processing plants, mining, and fracking cause more atmospheric deposition of toxic metals, soil erosion, and metal evaporation into the soil and groundwater.

When metal load becomes toxic

The toxicity of heavy metals depends on the dose, route of exposure, and the genetics of the exposed person. The metals that usually present the most significant degree of toxicity include arsenic, cadmium, chromium, lead and mercury. At varying rates of exposure, these toxic metals have adverse effects, including organ damage. Heavy metals are even classified as human carcinogens. On a more biological level, heavy metals have the potential to affect cellular health and the enzymes involved in metabolism, detoxification, and damage repair.

The largest method of exposure of these heavy metals occurs through environmental exposure, and the average daily intake is 50µg (microgram), coming from exposure to contaminated air, water, soil, and foods.  

How heavy metals affect the thyroid gland

A study from Iran concluded that toxic metals such as lead, cadmium, and chromium can increase the risk of both hypothyroidism and thyroid cancer. Mercury can trigger autoimmune reactions and oxidative damage, which plays a role in the pathogenesis of thyroid cancer, autoimmune thyroiditis, and hypothyroidism. Thyroid tissue was collected from 105 participants in a unique study that looked to see whether there was a prevalence of exposure to mercury. The study concluded that the proportion of those with measurable levels of mercury in their thyroid cells increased with age and it was well present in over one-third of those aged 60 years or older. Additionally, a 5 year-long study of over 4,000 participants with thyroid disease evaluated participants’ blood and urine samples for metal exposure. The study concluded that environmental heavy metal exposure may pose a particular risk to thyroid problems, especially that of cadmium. Cadmium especially is known to disrupt thyroid hormone secretion, as it interrupts thyroid function entirely by disturbing the conversion of T4 into active T3. Manganese at toxic levels can also affect TSH levels.

Common symptoms of heavy metal toxicity include:

  • Abdominal pain
  • Chills or low body temperature
  • Dehydration
  • Diarrhea
  • Feeling weak
  • Nausea or vomiting
  • Scratchy feeling in your throat
  • Numbness in hands and/or feet

More severe symptoms include:

  • Arrhythmia or abnormal heartbeat
  • Anemia
  • Brain damage and memory loss
  • Difficulty breathing
  • Kidney and/or liver damage
  • Miscarriages

If you have thyroid disease and haven’t been tested for elevated levels of heavy metals, or you suspect that you might have measurable heavy metal exposure, it’s always best to test and not guess. A heavy metal test usually consists of both serum (blood) and urine samples to check for the most prevalent heavy metal levels, including arsenic, cadmium, chromium, lead, and mercury. It is advised to avoid consuming seafood or wine 24 hours before collecting test samples, as both can interfere with the results.

How to safely reduce metal toxicity

Limiting your exposure to unnecessary high amounts of heavy metals is always the best cause of staying safe and reducing your toxic load.

1) Limit the amount of high mercury fish such as tuna and instead always opt for low mercury fish. To help remember, think " SMASH"  -- sardines, mackerel, anchovies, salmon, and herring.

2) Invest in a water filtration system for both tap and drinking water in your home. If a sophisticated system is not accessible, you can also purchase filters that easily snap onto a shower head and sink faucet and drinking water systems such as Berkey.

3) Read ingredients on all products purchased, and inspect for any signs of metal usage, such as baby food containers.

4) Check for adequate levels of zinc, iron, selenium and calcium. These minerals, especially when low, can lead to greater absorption of heavy metals such as cadmium and lead. Zinc alleviates oxidative stress, iron reduces the expression of cadmium absorption, selenium is a cofactor of glutathione which helps protect against oxidative stress and calcium helps prevent tissue damage.

5) In addition, be sure your vitamins are in check too. Deficiencies in vitamins C, B1 and B6 are reported to enhance the sensitivity of both cadmium and lead toxicity. Vitamins C and E especially are both non-enzymatic antioxidants that search for free radicals and reduce oxidative stress. B vitamins help to decrease lead levels in the liver, kidneys, bone and blood.

6) Increase intake of herbs, spices, and plants. Because of the phytochemical profile of plants, this can promote adequate vitamin and essential mineral levels. Consume more garlic, ginger, onion, green tea, grapes, curry leaves, and honey.

A note from Paloma

Mother Nature always presents us with the primarily medicinal needs for our body. If you are wanting to prevent your exposure to high metal load, focus on the guidance above. If you are experiencing uncomfortable and unwanted symptoms and suspect that you might be experiencing the effects of toxic metal exposure, reach out to your healthcare provider for testing. And when it comes to hypothyroidism care, you can turn to our team of thyroid-savvy doctors at Paloma Health for your thyroid health and a healthy thyroid lifestyle.

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Neeyaz Zolfaghari

Holistic Nutritionist and Nourishment Coach

Neeyaz Zolfaghari is the founder of Unspoken Nutrition, a nutrition and lifestyle brand dedicated to helping others find and create harmony with their daily habits to support their wellbeing and ‘health’. Her journey began over a decade ago, when she was diagnosed with two autoimmune diseases. Knowing what she learned from her upbringing, Neeyaz turned to nutrition as the first pillar of her healing. As her body began to heal on a physical level, she began to learn how our minds, bodies and souls are all innately connected.  

Now as an Integrative Nutritionist and Patient Advocate, Neeyaz offers the people she works with the support, guidance, and tools they need in order to live a fulfilled life. While Neeyaz initially endeavored to make a difference at the individual level, her vision grew to embrace broader community impacts. She is currently pursuing her Masters in Public Health, serving as a testament to her unwavering commitment to instigate change on a grander scale.

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