Essential and Toxic Elements: What Your Body Might Be Telling You

Our bodies rely on a careful balance of essential elements to function optimally, but we're also exposed to potentially toxic elements through everyday environmental and dietary sources. Identifying the right levels of these elements can have a profound impact on health. Let’s explore what each element reveals and how advanced testing methods like dried urine and dried blood spot (DBS) testing provide critical insights.

Essential Elements

Iodine

Iodine is critical for thyroid hormone production (T4 and T3). Found in dairy, seafood, iodized salt, and grains, this nutrient must be present in the right amount: too little can cause thyroid deficiency, goiter, cognitive issues, and pregnancy complications; too much can paradoxically cause similar thyroid problems. Because over 90% of iodine is excreted in urine, dried urine testing offers an accurate snapshot of recent intake.

Selenium

This trace element is a key player in the body's antioxidant defenses and thyroid hormone activation. Selenium is found in foods like Brazil nuts, seafood, eggs, and whole grains. A narrow therapeutic window means that deficiency or excess can lead to problems. DBS and urine testing help monitor selenium levels and ensure it’s available to counteract the negative effects of toxic metals like mercury and arsenic.

Magnesium

Magnesium is vital for over 600 enzymatic processes including energy production, nerve function, and heart rhythm. Many people are unknowingly deficient. Common in green vegetables, nuts, and whole grains, magnesium is better assessed through DBS, which reflects intracellular stores—something serum testing often misses.

Zinc

Zinc supports immune health, wound healing, and cellular repair. Found in meat, beans, seafood, and whole grains, zinc must be balanced with copper to avoid issues like impaired immunity or cholesterol imbalance. Low zinc or high copper levels have been linked to conditions such as autism spectrum disorders. DBS testing provides a more complete picture of zinc status.

Copper

Copper is essential for energy metabolism, connective tissue development, and nervous system function. Too little can lead to neurological issues, while too much may cause liver damage. Zinc and copper balance is especially important, as excess zinc can lead to copper deficiency. Good dietary sources include shellfish, seeds, and whole grains.

Bromine

Bromine, found in flame retardants, certain medications, and food products, may have biological significance at low levels but can disrupt thyroid function—especially when iodine levels are low. Urinary bromine testing can help identify excessive environmental exposure.

Lithium

In trace amounts, lithium may promote brain health and mood regulation. Low environmental lithium levels have been associated with increased rates of mood disorders and violent behaviour. Dietary sources include grains, vegetables, and well water. Dried urine testing can help determine recent lithium intake and exposure.

Toxic Heavy Metals

Arsenic

A naturally occurring toxin, arsenic is found in water, rice, seafood, and fruit. It interferes with thyroid function, damages vital organs, and may contribute to cancer and diabetes. Urinary testing is the best way to assess arsenic exposure, as most of it is excreted in urine within 72 hours.

Cadmium

Cadmium exposure comes from smoking, industrial pollutants, and contaminated foods like leafy vegetables and shellfish. It accumulates in the kidneys, liver, and thyroid and may interfere with reproductive health and hormone balance. DBS and urinary cadmium levels reflect both short- and long-term body burden.

Mercury

Mercury exists in three forms—elemental, inorganic, and organic (methylmercury)—with exposure mainly from dental fillings, seafood, and some vaccines. It is highly toxic, especially to the brain and kidneys. Mercury competes with selenium, reducing thyroid function. Blood spot testing helps detect methylmercury (from fish), while urinary tests assess inorganic mercury exposure.

Creatinine: The Key to Accurate Urine Testing

Creatinine is a metabolic byproduct that reflects kidney function and hydration status. It’s used to normalize urine test results, ensuring that element levels are not skewed by how much water you've consumed.

Why Use Dried Urine and Dried Blood Spot Testing?

• Simple collection at home – No need for 24-hour urine collection.

• Stability – Samples remain stable at room temperature for weeks.

• Convenient shipping – Easy to send by mail from anywhere in the world.

• Accurate normalization – Urinary results are adjusted for hydration using creatinine (µg/g).

In Summary
Understanding your body's exposure to essential and toxic elements is a vital component of personalised healthcare. With cutting-edge testing methods like those from ZRT Laboratory, individuals and practitioners can better detect imbalances and make informed decisions to support optimal health.

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