How Bad Are Amalgam Fillings?

You probably already know this. oral healthIt is one of my passions. I’ve had several dentists on the podcast to discuss common dental health questions, and one reoccurring topic is how to prevent tooth decay and cavities. What’s the big deal about cavities and amalgam fillings? Well, besides the pain, expense, and annoyance of getting a filling, there’s also what’s in the filling to consider (hint: it isn’t good).

What are Amalgam Fillings?

Dental amalgam is a tooth-filling material that contains about 50% mercury. The remaining 50% is a tin or copper alloy. These silver fillings are common in many people’s teeth. This material has been used for many years in dentistry.

How bad are amalgam fillings anyway?

Amalgam fillings, while very common, can also be toxic. Here’s what you need to know about them.


Mercury, a highly toxic substance for the body, is contained in amalgam fillings. Mercury is a neurotoxin, and also a reproductive poison. Studies have shown that mercury levels can be linked to inflammatory diseases.

Mercury is released into your body when:

  • The dentist places or removes the tooth amalgam.
  • You chew food or gum
  • You brush your teeth
  • You grind your teeth

The FDA reviewed scientific evidence regarding amalgam fillings in 2009. The FDA reclassified mercury as a class I risk (lowest risk) to a category II risk (higher risk). It also classified amalgam-filled cavities as a class 2 risk. The FDA wrote this in their guidance document.

“(D)ental amalgam also releases low levels of mercury vapor, a chemical that at high exposure levels is well-documented to cause neurological and renal adverse health effects. Mercury vapor concentrations are highest immediately after placement and removal of dental amalgam but decline thereafter.”

Strangely enough, the FDA still considers amalgam-fillings safe for adults over six years of age. Here’s a history of new regulations over the past decade:

  • The World Health Organization called in 2011 for the phasing out amalgam fillings.
  • The FDA was challenged by the public to protect them from amalgam fillings in 2011.
  • The United Nations Minamata Convention on Mercury was adopted as an international treaty in 2013. This treaty required all countries to define many mercury-containing products. It also requires that all mercury mining cease within 15 years. They reached the milestone of 50 ratification in May 2017. This means that at least 50 countries have signed the treaty, and the process of eliminating mercury mining could begin. Though the U.S. government has agreed to this treaty, we haven’t seen much done yet.

In 2016, researchers discovered (in a 2003-2004 study) that people with eight or more dental fillings had 2.4x the mercury in their blood compared to those who had none. In a 2011-2012 study, a second group found a similar correlation, but it was slightly lower, probably because composite fillings (nonmercury) were more common. The EPA considers mercury safe at.002 mg/L.

One of the researchers mentioned this was only an average, which means some people had levels higher than the EPA’s limit. Add in mercury from other sources, such as fish consumption and vaccines.Some people can have dangerous levels of mercury in their bodies.

This study also found increases in the more dangerous form of mercury—methylmercury—which is known to be dangerous at much lower levels.

The American Dental Association (ADA) responded to the research by releasing a statement reaffirming its position that “dental amalgam is a safe, durable, and effective cavity-filling option.” They went on to say that no conclusions should be drawn about safety from this study.

Bottom line: Mercury is a known toxins, and amalgam fillings can release mercury into the body. When we have plenty of alternatives to amalgams, there’s just no reason to continue using them.

Tooth damage

The temperature changes can cause the filling material to shrink or expand, which can result in cracking and breaking. Dentists will need to remove some of the healthy areas of the teeth in order to place the amalgam filling. This weakens the tooth, making it more vulnerable to cracking and breaking (and more dental procedures in future). Composite fillings are less likely to require the removal of healthy parts of the tooth.

Environmental Issues

Mercury pollution is also a problem. Mercury from dental mercury can enter the environment through:

  • Air – cremation smoke, sewage sludge, waste incineration, and dentist clinic emissions
  • Water – human waste disposal and dental clinics
  • Land – landfills, burials, and fertilizers

Mercury is released into the environment by microorganisms, which convert elemental mercury to methylmercury. This mercury builds up in fish, shellfish and those who eat mercury-containing seafood. Methylmercury can cause damage to children’s and fetuses’ developing brains and nervous systems.

Mercury in fillings is not only harmful to the person filling them, but also to everyone else (especially fish eaters).

Signs of Mercury Toxicity

The amount of mercury in the body isn’t a direct representation of whether mercury is being harmful. Studies have shown that mercury in the body triggers pro-inflammatory immune cells which can increase the risk of developing infectious or autoimmune diseases.

Inflammation can also make your body more vulnerable to mercury toxicity. Amy Nett, in a guest blog on Chris Kresser:

“In one study, inflammation due to different causes, including exposure to bacterial endotoxin, which occurs with food poisoning or other GI infection, significantly increased toxicity. Another study found that small amounts bacterial endotoxin exposure significantly increased susceptibility for damage from various toxins including metals. Another study in mice found that mercury in the presence bacterial endotoxin caused more kidney damage than normal. This means that the same amount of mercury or other toxins will cause more damage in the presence of inflammation.”

The way mercury toxicity plays in a body is different for everyone. Here are some signs and symptoms that can indicate mercury poisoning:

  • Depression or anxiety
  • Memory problems, brain fog, decreased concentration
  • Fatigue
  • Frequent headaches
  • Feeling uncoordinated/lacking motor skills
  • Autoimmune disease
  • Allergies
  • Multiple chemical sensitivity
  • Nerve damage (phantom pain, sensations)
  • Hearing loss
  • Slow or slurred speech
  • Muscle tremors
  • Hair loss
  • Hormonal dysregulation includes infertility and abnormal menstrual cycles.
  • Cardiovascular disease
  • Kidney dysfunction

In children:

  • Sleep disturbance
  • Motor skills that are impaired or delayed
  • It is difficult to learn how to speak
  • Problems with hand-eye coordination

Many of these symptoms could indicate other illnesses or causes, so it’s essential to work with a knowledgeable naturopath or functional medicine doctor to determine what’s causing your or your child’s symptoms.

A hair mineral analysis test will reveal if you have excess metals in your body.

You may need more testing, because a hair mineral test may not suffice. That is why it is so important that you consult a doctor.

Alternatives to Amalgam Filings

As I mentioned, there are many alternatives to amalgam fillings. Here are the safest and most effective alternatives to mercury fillings.

Composite Resin

Composite resin fillings are made from a type (an acrylic resin) and reinforced with powdered, tooth-colored glass filler. Composite fillings contain BPA, but studies have found no correlation between the number of fillings and levels of BPA in the blood (suggesting that composite fillings don’t release BPA the way amalgam fillings release mercury). While it is best to avoid either, composite is a better choice than amalgam. Composite fillings can also last a long time.

Natural Remineralizing Cavities

As Dr. Weston A. Price (a dentist) discovered and detailed in Nutrition and Physical Degeneration, some cultures throughout the world had perfect teeth despite no access to dentists or modern toothpaste. However, tooth decay rates were very high in similar cultures that had different diets.

He and others discovered that diet was the most important factor in tooth structure. Yes, diet also affects the need for braces.

A diet that strengthens teeth (versus one that causes decay) has three major components:

  1. Enough dietary vitamins
  2. Enough dietary fat-soluble vitamins A, D, E and K
  3. These nutrients can be bioabsorbed and absorbed by people.

I made a change in my diet to improve my dental health. I actually remineralized some cavities!

What to do if your Amalgam Fillings are Already In Use?

If you already have some amalgam fillings and want to get them removed, it’s not as simple as going to your regular dentist. The removal of amalgam fillings can release a lot of mercury into the body, and many dentists don’t know how to remove amalgam fillings safely. A holistic dentist, also known as a biological dentist, can safely remove amalgam fillings. Find one near to you:

Are you a victim of amalgam fillings? How was it?

  1. Gump, B. B., et al. (2011 October 24). Fish consumption, low-level mercury, lipids, and inflammatory markers in children. Environmental Research.
  2. Center for Devices and Radiological Health. (n.d.). Appendix I : Summary of changes to the classification of Dental Amalgam. U.S. Food and Drug Administration.
  3. WHO. (n.d.). Future use of materials for dental restoration.
  4. International Academy of Oral Medicine and Toxicology. (2018, June 30). Public demands FDA take immediate action on Mercury fillings.
  5. Environmental Protection Agency. (n.d.). Minamata Convention on Mercury. EPA.
  6. MacMillan, A. (2016, October 4, 2016). How dental fillings can impact mercury levels on your blood. Time.
  7. Novo, J. P., et al. (2021). Cellular and Molecular Mechanisms Mediating Methylmercury Neurotoxicity and Neuroinflammation. International journal of molecular science, 22(6), 3101.
  8. What is dental amalgam? (n.d.).
  9. Gardner, R. M., et al. (2009, December). Mercury induces an unopposed inflammatory response in human peripheral blood mononuclear cells in vitro. Environmental health perspectives.
  10. Nett, A. (2015, August 11). Mercury toxicity – is it the cause for your symptoms. Chris Kresser.

Leave a Reply

Your email address will not be published. Required fields are marked *