A woman in her 50s had multiple dental mercury amalgam fillings placed during childhood—the routine treatment at a time when dental care offered few alternatives. Although durable, the fillings can be a source of chronic mercury exposure.

Decades later, she had the amalgams removed by a dentist who was not trained in safe removal protocols. During drilling, toxic mercury vapor was released and rapidly absorbed through her oral cavity into her brain and nervous system.

Soon after, devastating symptoms emerged: sudden, profound memory loss, chronic insomnia, emotional turmoil, and roving, electric-shock-like neuropathic pain. Her immune system weakened sharply, leading to frequent illnesses, loss of appetite, and an inability to perform everyday activities. Her life unraveled.

The consequences extended beyond the patient—the treating dentist also suffered health complications from the unprotected exposure to mercury vapor.

Mercury: Acute and Chronic Hazards

Dr. Lin Shao-zhen, a neurologist and director of Pinxin Clinic, presented the above mercury-poisoning case—the most severe she has ever handled—to raise public awareness of the hidden dangers of mercury exposure.

In an episode of “Health 1+1” on NTD, a sister outlet of The Epoch Times, Lin recommended that people with mercury amalgam fillings should seek treatment only at dental clinics equipped with professional mercury-removal tools and staffed by trained practitioners.

For physicians, Lin suggested optimizing a patient’s nutritional status before proceeding with mercury removal. This ensures normal liver and kidney function and builds sufficient antioxidant capacity, thereby minimizing heavy metal damage during the procedure.

In addition to acute poisoning, chronic mercury overload is equally dangerous, potentially triggering a range of symptoms, including chronic pain, autoimmune disorders, insomnia, tremors, and impairments in liver or kidney function and blood sugar regulation. In children, mercury exposure may increase the risk of attention-deficit/hyperactivity disorder and learning difficulties.

Beware Heavy Metals in Fish

The adage claims that “eating fish boosts brainpower,” however, Lin said that selecting the wrong species can have the opposite effect—potentially harming memory and brain function. Environmental mercury enters the food chain via plankton, she said. Small fish accumulate it first, and concentrations rise dramatically with each step up the trophic ladder. As a result, large predatory species such as tuna, swordfish, and shark harbor the highest levels of methylmercury—the form most toxic to the nervous system.

Many mistakenly assume that heavy metals concentrate mainly in a fish’s head, skin, or organs; however, Lin said they primarily accumulate in the muscle tissue—the flesh we most often eat. By comparison, the skin is relatively safe, whereas organs tend to retain mostly inorganic mercury.

Occasionally eating large predatory fish poses little risk for most adults. However, Lin urged pregnant women and children to avoid them entirely. Safer choices are small fish about the size of an adult’s palm—lower on the food chain, they contain far less accumulated heavy metals.

Lead: The Ever-Present Threat

Beyond mercury, lead remains one of the most insidious and overlooked heavy metals. Lin recounted a case where a patient suffered rapid cognitive decline, slowed movements, profound memory loss, and disrupted circadian rhythms—symptoms closely mimicking atypical Parkinson’s disease. A detailed investigation identified the likely culprit as long-term use of lead-contaminated cookware.

Lead’s toxicity is far-reaching and multifaceted. Chronic exposure can impair vascular smooth muscle function, narrowing blood vessels and raising the risk of cardiovascular disease. In children during critical brain development stages, even low-level exposure can cause attention deficits, delayed language skills, and an increased likelihood of cognitive impairment later in life. For women of reproductive age, lead poisoning may elevate risks of infertility and miscarriage.

These health threats can stem from hidden sources within our homes. Lin said that many unexpected routes of lead exposure exist in daily life:

• Brightly Colored Cups and Utensils: To achieve brighter, more vivid hues and greater contrast, some manufacturers add lead and other heavy metals to glazes or coatings. If these coatings have poor adhesion, lead can gradually leach out during routine washing or when the vessels are used to hold acidic or hot foods.


• Lead Pipes in Older Houses: If an old house still has lead pipes, the water running through them may contain lead.


• Paints and Building Materials From Before the 1960s: When old, colorful paints chip off, touching them with bare hands or cleaning without proper protection can cause lead to enter the body through skin contact or inhalation.


• Cosmetics: For example, Kohl eye makeup contains ingredients such as lead powder. Applying it directly around the eyes poses significant health risks.


• Cheap Metal Jewelry: Some inexpensive jewelry uses lead alloys to increase weight. Prolonged contact with the skin can lead to absorption into the body.

How to Assess Heavy Metal Risk and Protect Yourself

If you’re struggling with chronic pain, memory decline, or autoimmune disorders, and are meeting any of the following conditions, you may be at high risk for heavy metal poisoning if you:

• Have Mercury Fillings: Lin routinely checks for and examines mercury fillings in consultations.


• Frequently Eat Large Fish: Certain fish and other seafood may lead to the accumulation of heavy metals.


• Smoke or Are Exposed to Secondhand Smoke: Tobacco smoke contains heavy metals.


• Have Occupational Exposure: Working with machinery, organic solvents, auto repair, or factory environments with metal dust may lead to heavy metal toxicity.


• Live in a Home Near Environmental Risks: Living near industrial zones or coal-fired power plants can lead to exposure.


• Take Herbal or Traditional Chinese Medicines of Unknown Origin: Some herbs may be contaminated with heavy metals during cultivation or processing.

For daily prevention of heavy metal poisoning, Lin suggested:

When purchasing everyday items, select only those bearing certified safety labels, and replace cookware and tableware regularly. Steer clear of vessels from unknown sources, those with excessively bright colors, or any showing scratches or wear. In older homes, keep children away from peeling paint to prevent contact or ingestion.

For cooking, Lin recommended stainless steel and cast-iron pots. Choose cast iron with a natural matte-black interior over colorful enameled versions. Even if scratched, it primarily releases iron—an essential trace element beneficial to the body. Scratched stainless steel may leach small amounts of iron, nickel, and chromium. While nickel can trigger reactions in sensitive individuals, cast-iron pots are generally safe for most people.

How to Safely Reduce Heavy Metal Burden

While eliminating stored heavy metals from the body often requires medical supervision, Lin noted that we can significantly reduce exposure risk and support the body’s natural detoxification through targeted diet and lifestyle changes.

Incorporate Detox-Supporting Foods

• Sulfur-Rich Foods: Garlic, onions, leeks, broccoli, cauliflower, coriander, and other sulfur-containing vegetables support liver function and maintain its detoxification capacity.


• Balanced Mineral Intake: Supplementing with iron, selenium, calcium, magnesium, and zinc enables these essential minerals to compete with heavy metals for cellular receptors, thereby reducing metal absorption.


• Antioxidants: Vitamins C and E exhibit potent antioxidant activity, neutralizing free radicals generated by heavy metals and thereby minimizing oxidative cellular damage.


• Liver-Supporting Nutrients: Alpha-lipoic acid, N-acetylcysteine, and glutathione promote detoxification processes.

Lin underscored the importance of dietary variety—aim for a broad range of foods and avoid eating any single item, even if it is considered healthy.

Revamp Your Lifestyle

• Stay Well-Hydrated: Water is the primary medium in which the kidneys filter and eliminate toxins.


• Support Gut Health: A balanced intestinal microbiome serves as a critical protective barrier in the body.


• Promote Regular Bowel Movements: This reduces the chance of toxins being reabsorbed in the intestines.


• Encourage Regular Sweating: Toxins can be excreted via sweating during exercise, foot baths, or sauna sessions.