Earthing Mat Dangers: Safety Risks, Medical Concerns, and What the Research Says

10 min read

What Is an Earthing Mat and How Does It Work?

An earthing mat (also called a grounding mat) is a conductive pad, usually made of carbon-infused rubber or silver-threaded fabric, that connects to the ground wire of your electrical outlet via a cord and plug. The idea is simple: the mat creates an electrical connection between your body and the Earth's surface, mimicking what happens when you walk barefoot on grass or soil.

The theory behind earthing is that direct contact with the Earth's surface allows free electrons to flow into your body, neutralizing free radicals and reducing inflammation. Proponents claim this can improve sleep, reduce pain, lower stress hormones, and speed recovery. The concept was popularized by Clint Ober, a retired cable TV executive, and has grown into a multi-million dollar industry.

Whether the theory holds up to scrutiny is a separate question from whether the products are safe. Even if earthing works as claimed, the devices used to deliver it introduce risks that are rarely discussed in marketing materials. That is what this article addresses.

What Earthing Mats Claim to Do

Before addressing the dangers, it is fair to acknowledge what earthing products claim and where those claims stand.

The most commonly cited benefits include improved sleep quality, reduced inflammation, lower cortisol levels, decreased pain, and faster wound healing. A 2015 review published in the Journal of Inflammation Research (PMC4378297) compiled evidence from multiple small studies and reported improvements in sleep, cortisol regulation, and wound healing in grounded subjects.

However, and this matters for understanding the landscape, the study's authors disclosed a conflict of interest: the research was supported by Earth FX Inc., a company that sells earthing products. The sample sizes were small (typically 10-30 participants), and several studies lacked proper blinding. This does not mean the findings are wrong, but it does mean they should be interpreted cautiously.

For a more detailed look at the evidence for and against, our article on whether grounding mats are a hoax covers both sides in depth.

The Real Dangers of Earthing Mats

Here is where the conversation needs to be honest. Most earthing mat retailers present these products as completely safe and natural. The reality is more nuanced.

1. Electrical shock from faulty home wiring

This is the most serious and least discussed danger. An earthing mat connects to your home's ground wire. If your home's electrical grounding is faulty, damaged, or improperly installed, the mat can expose you to stray voltage or ground currents.

In older Canadian homes (pre-1960s), many outlets were installed without proper grounding. Even in newer homes, ground connections can degrade over time from corrosion, rodent damage, or poor installation. A 2019 report from the Electrical Safety Authority of Ontario noted that grounding deficiencies were found in approximately 12% of inspected residential properties.

If you plug an earthing mat into a faulty ground, you are not connecting to the Earth. You are connecting to whatever electrical potential exists in that wire, which could include leakage current from appliances, nearby lightning strike residuals, or voltage from wiring faults.

2. EMF and dirty electricity exposure

This is ironic, since many people buy earthing mats specifically to reduce EMF exposure. But research from building biologists suggests that in some home environments, connecting to the ground wire can actually increase your body voltage by acting as an antenna for electromagnetic fields from household wiring.

The effect depends on your home's wiring configuration, the proximity of electrical cables to the mat, and the overall electromagnetic environment. In high-EMF environments (near electrical panels, bundled wiring, or in multi-unit buildings), grounding can sometimes increase rather than decrease your electromagnetic exposure. Our EMF-free bedroom guide covers this topic in more detail.

3. Skin reactions and irritation

Some earthing mats contain silver threads or carbon-based conductive materials that can cause contact dermatitis in sensitive individuals. Prolonged skin contact (overnight use) increases the risk compared to brief daytime use. Several users have reported rashes, itching, and skin discolouration after sustained use.

If you have known metal allergies, particularly nickel or silver sensitivities, test the mat on a small area of skin before committing to overnight use.

4. Blood-thinning effects

This one is rarely mentioned but potentially serious. A 2013 study in the Journal of Alternative and Complementary Medicine found that earthing significantly reduced blood viscosity (thickness), which the researchers framed as a cardiovascular benefit. The problem is that reduced blood viscosity is essentially a blood-thinning effect.

For people already taking blood-thinning medications (warfarin, Coumadin, heparin, or even daily aspirin), adding an additional blood-thinning mechanism without medical supervision could increase bleeding risk. This interaction has not been studied, which is itself a concern.

Electrical Safety: The Risk Nobody Talks About

Most earthing mat injuries are not dramatic electrical shocks. They are subtle, chronic exposures that users may not even recognize as problems: disrupted sleep attributed to other causes, unexplained tingling, or headaches blamed on stress.

The fundamental issue is that earthing mats depend entirely on the quality of your home's electrical ground. Most people have no idea whether their grounding is adequate, and earthing mat sellers rarely emphasize this prerequisite.

Lightning is another consideration. While earthing mat cords typically include a built-in resistor to limit current, a nearby lightning strike can send a surge through the ground system that exceeds the resistor's capacity. During thunderstorms, the safest practice is to unplug the mat entirely.

Who Should NOT Use an Earthing Mat

Cleveland Clinic and other medical sources identify several groups who should avoid earthing mats or use them only under medical supervision:

• People with pacemakers or implanted medical devices: Ground currents, even small ones, can interfere with pacemaker function. This is not theoretical. Medical device manufacturers explicitly warn against sustained contact with grounded surfaces for this reason.
• People on blood-thinning medications: The potential blood-thinning effect of earthing could compound with medication effects. Consult your doctor before using.
• Pregnant women: The effects of sustained grounding on fetal development have not been studied. Cleveland Clinic advises caution.
• People with nerve damage or neuropathy: Reduced sensation means you may not feel electrical discomfort that would alert a healthy person to a problem.
• People with compromised immunity: Some conductive materials harbour bacteria and are difficult to fully clean. Immunocompromised individuals should be cautious about sustained skin contact with any poorly cleaned surface.
• People taking thyroid medication: Anecdotal reports suggest earthing may affect thyroid function, potentially altering medication requirements. While not confirmed in studies, monitoring thyroid levels after starting earthing use is prudent.

What the Research Actually Shows

The honest answer is: not enough to draw firm conclusions in either direction.

The 2015 review in PMC4378297 is the most comprehensive compilation of earthing research. It reports positive findings across multiple small studies, including improved sleep, reduced cortisol, decreased pain, and faster wound healing. But it also acknowledges that most studies were industry-funded, had small sample sizes, and lacked robust blinding protocols.

A 2023 review in the Bioelectricity journal noted that while the theoretical mechanisms of earthing are plausible (electron transfer, inflammatory modulation), the clinical evidence remains "preliminary" and "requires larger, independent, well-controlled studies."

No major health agency in Canada (Health Canada), the US (FDA, NIH), or internationally (WHO) has endorsed earthing products for any health claim. This does not mean they do not work, but it means the evidence has not met the standard required for medical endorsement.

What we find telling is that the most rigorous research has focused on the benefits of earthing while the safety profile has received almost no independent study. The dangers listed in this article are extrapolated from electrical engineering principles, medical device safety guidelines, and clinical observations, not from dedicated safety trials of earthing products. That gap in the research is itself a concern.

How to Use an Earthing Mat Safely (If You Choose To)

If you have reviewed the risks and want to try an earthing mat, these precautions reduce your exposure to the known dangers:

1. Test your outlet's ground. Use a $15 outlet tester. If it shows any fault, do not use the mat on that outlet.
2. Consider hiring an electrician. For $75-150, an electrician can verify that your home's grounding system is intact and properly bonded. This is especially important in older Canadian homes.
3. Start with short sessions. Use the mat for 30-60 minutes while reading or watching TV before committing to overnight use. Monitor for any skin reactions, tingling, or unusual sensations.
4. Unplug during thunderstorms. Lightning surges can travel through ground connections.
5. Keep the mat clean. Follow the manufacturer's cleaning instructions carefully. Conductive materials can harbour bacteria.
6. Monitor your medications. If you take blood thinners or thyroid medication, inform your doctor that you are using an earthing product and monitor for any changes in how your medications are working.
7. Consider outdoor grounding instead. Walking barefoot on grass, soil, or sand gives you the same theoretical benefit without the risks associated with indoor electrical connections.

Alternatives Worth Considering

If the concept of grounding appeals to you but the safety concerns give you pause, there are alternatives that carry fewer risks:

Barefoot outdoor time: The original form of earthing. Walking barefoot on natural surfaces (grass, soil, sand, even concrete) provides direct Earth contact without the electrical intermediary of your home wiring. A 2012 study in the Journal of Environmental and Public Health found that outdoor grounding reduced blood viscosity and improved cardiovascular markers. Even 20-30 minutes daily during warmer months may provide the benefits earthing mat proponents describe.

Sleep environment optimization: Many of the benefits attributed to earthing (better sleep, lower stress, reduced pain) can be achieved through well-established sleep hygiene practices: a cool bedroom (15-19 degrees), dark environment, consistent sleep schedule, and a comfortable mattress. These interventions have decades of research behind them and carry no safety risks.

Grounding sheets with proper testing: If you want a grounding sheet for sleep, choose products from reputable manufacturers that include built-in safety resistors, and always test your outlet first. Our guide to grounding sheets in Canada covers specific products and what to look for.