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Mercury Poisoning Symptoms & How to Avoid or Recover from Them
September 28, 2016
Mercury poisoning is the result of exposure to mercury, a heavy metal that’s seriously toxic to our health. Numerous studies have shown that high exposure to mercury changes and poisons the central nervous system, which can result in irritability, fatigue, behavioral changes, tremors, headaches, hearing and cognitive loss, hallucinations and even death. Mercury exposure can also negatively affect the cardiovascular system, causing high blood pressure in humans and animals. (1)
Ideally, we would all have zero mercury internally present in our bodies. However, due to our diets, environmental exposure, choice of fillings and more, almost every single person in the world has at least trace amounts of mercury in his or her body.
Mercury poisoning is typically not a health problem that occurs overnight. It takes time for mercury levels to build up in the blood. Naturally, mercury slowly leaves the body through urine, feces and breast milk. However, if you consume a great deal of fish high in mercury, it can actually take up to a year for your mercury levels to go down after you stop eating the mercury-rich fish. (2) This may sound like a ridiculous amount of time, but you have to consider that when you eat seafood containing methylmercury, over 95 percent of the mercury can be absorbed into your bloodstream. It can then travel throughout your body and penetrate the cells of various tissues and organs where it can remain stored up for years, which can cause symptoms that you may or may not realize are the result of mercury poisoning. (3)
While there is no way to entirely avoid mercury as long as you live on planet Earth, there are many ways to naturally reduce your exposure and intake. Mercury serves zero purpose in our bodies, which means we ideally want to reduce our mercury exposure as much as possible. According to the Environmental Protection Agency, the most common way we’re exposed to mercury in the U.S. is by consuming fish containing this health-hazardous heavy metal. (4) I’m going to tell you about some natural ways to reduce your exposure and also how to reduce the mercury that has already accumulated in your body, along with how to tell if you may have mercury poisoning.
Mercury Poisoning Symptoms and Who Is Most Affected
What is mercury? Mercury (Hg) is a heavy metal that can be found in the Earth’s crust. It’s released into the environment with natural phenomenons like volcanic eruptions. Mercury commonly occurs in three forms: elemental, inorganic and organic. In nature, mercury is mainly found within compounds and as inorganic salts. It’s rarely found as a liquid metal in nature.
Human activities, like coal burning and gold mining, are currently the main sources of mercury being released into our environment. Metallic or elemental mercury (an odorless, shiny, silver-white liquid) is commonly used in thermometers, barometers and fluorescent light bulbs. Due to valid concerns over mercury’s toxicity, mercury thermometers have been phased out of most hospitals and other clinical facilities. Mercury poisoning can occur as a result of being exposed to water-soluble forms of mercury (like methylmercury), inhaling mercury vapors, or by ingesting any form of mercury.
When it comes to mercury levels in our bodies, a normal whole blood mercury level is considered to be between zero and nine nanograms per milliliter (ng/mL). People who have regular, mild exposure to mercury due to their occupations, like dentists, may regularly have whole blood mercury levels up to 15 ng/mL. (5)
People who receive amalgam fillings may be at risk, too. In September 2016, researchers published a first-of-its-kind study showing amalgam fillings significantly contribute to prolonged mercury levels in the body. The University of Georgia researchers also identified the magic number of mercury fillings it takes to increase levels in the bloodstream. The results show that individuals with more than eight fillings had about 150 percent more mercury in their blood than those with none. The average American has three dental fillings; 25 percent of the population has 11 or more fillings. (6)
Here’s what one of the researchers had to say:
“As toxicologists, we know that mercury is poison, but it all depends on the dose. So, if you have one dental filling, maybe it’s OK. But if you have more than eight dental filings, the potential risk for adverse effect is higher. People with numerous dental fillings who are also exposed to mercury from other sources, such as seafood or work environments, are most at risk.” – Xiaozhong “John” Yu, assistant professor of environmental health science and co-author of the study
Elemental mercury is found in dental fillings as well as glass thermometers, fluorescent light bulbs and electrical switches. Chronic symptoms of elemental mercury exposure may include: (7)
- Metallic taste in the mouth
- Vomiting
- Difficulty breathing
- Bad cough
- Swollen, bleeding gums
Permanent lung damage and death may occur depending on how much mercury has been inhaled. Long-term brain damage is also possible.
Organic mercury, or methylmercury, is found in fish along with fumes from burning coal. Long-term, accumulated exposure to this type of mercury will likely cause symptoms in the nervous system, including:
- Numbness or pain in certain parts of your skin
- Uncontrollable shaking or tremor
- Inability to walk well
- Blindness and double vision
- Memory problems
- Seizures and death (with large exposures)
When it comes to high levels of mercury, pregnant women really have to be the most careful. According to the National Institute of Environmental Health Sciences, pregnant women who consume high-mercury fish regularly risk permanently damaging their developing fetuses. And we’re not talking about minor damage either. Children born to these mothers have been known to exhibit cognitive deficits, motor difficulties and sensory problems. (8) The mercury warning for moms-to-be is definitely real and really worth listening to for the sake of your unborn baby.
Related: Metal in Baby Food: Study Finds 95% Contain Heavy Metals
Common Causes of Mercury Poisoning
According to research published in Environmental Health in 2007, the general population’s top sources of mercury exposure are methylmercury (MeHg) from seafood, inorganic mercury (I-Hg) from food and mercury vapor (Hg0) from dental amalgam restorations. This same research concluded that getting mercury from our diets (mainly through fish) has “a marked impact” on mercury concentrations in the brain while exposure to amalgam fillings increases the mercury concentrations in the brain. (9)
Amalgam/Mercury Fillings
Do you have amalgam fillings? You might actually know them as “mercury fillings” or “silver fillings.” Chances are if you’ve ever had a cavity filled, it’s been filled with amalgam, which is is one of the most commonly used tooth fillings for tooth decay. (10) Once you know about mercury it seems hard to believe, but mercury is still commonly used in dentistry today. Amalgam is composed of liquid mercury (about 50 percent by weight) and powdered alloy metals silver, tin and copper. This filling material appears silver in color, giving it the nickname “silver fillings.”
According to Mayo Clinic Medical Laboratories, mercury is released from an amalgam filling daily by the simple and necessary act of chewing. The daily amount is said to be two to 20 micrograms a day. Chewing gum causes the release of mercury from amalgam fillings “greatly above normal.” To make a concerning situation even more concerning, our mouth’s flora converts some of this mercury to oxidized mercury and methylmercury, which have been shown to then be incorporated into the body’s tissues. (11)
Experts like to say that the amount of mercury released by an amalgam fillings isn’t significant enough, but it’s all about the daily exposure plus the accumulation of mercury. A filling that’s in your mouth for decades has a lot of time and many daily opportunities to release mercury into your tissues.
High-Mercury Fish
In the U.S., fish consumption is said to be our main source of mercury. The highest concentrations of methylmercury are generally found in large fish that eat other fish. Fish high in mercury include tilefish, swordfish, shark, king mackerel and bigeye tuna. (12) Those are the top five fish when it comes to high mercury levels with tilefish the highest in mercury. Unfortunately, cooking a piece fish doesn’t make it lower in mercury. The mercury in fish is not changed significantly by cooking so both raw and cooked versions of a fish have similar mercury levels.
You might be wondering how mercury even gets into fish. According to a 2014 Consumer Reports article, mercury levels in the northern Pacific Ocean have risen around 30 percent over the past 20 years and are expected to rise by 50 percent more by 2050 as industrial mercury emissions increase. This is according to a 2009 study by the U.S. Geological Survey and Harvard University. Larger, predatory fish are higher in mercury because they have more tissue to accumulate mercury, and they also tend to live longer than smaller, low-mercury fish like sardines, sole and trout. (13)
Herbal Medicines
Herbal medicines made outside of the U.S. have been known to contain toxic levels of mercury. Since these products aren’t controlled by the Food and Drug Administration, they aren’t required to live up to any specific purity standards. This is yet another reason to choose your herbal supplements very carefully. (14)
Related: California Bans Chemicals in Beauty Products
Ways to Naturally Recover and Avoid Mercury Poisoning
Reduce Exposure
If you know you have high levels of mercury, you need to stop your exposure immediately. If you know that the main source of mercury in your daily life is your intake of fish, stop eating high-mercury fish and opt for other mercury-free protein options. When it comes to the mercury found in fish, the FDA and EPA advise women who may become pregnant, pregnant women, nursing mothers,and young children not to eat fish high in mercury and to eat limited amounts of fish and shellfish that are lower in mercury. (15)
Specifically Cut Back on Tuna and Other Fish
Tuna salad is a quick and easy lunch option loved by so many. Unfortunately, tuna is also said to be the most common source of mercury exposure in this country. If you love tuna, reduce your mercury intake by choosing light or skipjack and keep your intake under two servings each week. For young kids, keep it around four ounces per week. When it comes to albacore tuna, developing children are supposed to avoid it completely, and women who plan on getting pregnant should not have more than four ounces of albacore each week. (16)
In general, try to eat more of the less predatory and smaller fish that are considered low-mercury fish. Again, the top fish when it comes to mercury levels include tilefish, swordfish, shark, king mackerel and bigeye tuna. So avoid or limit those as much as you can. Instead, opt for fish like salmon, sardines and anchovies that are also high in health-promoting omega-3 fatty acids.
Heavy Metal Detox
To help your body get rid of mercury, you can follow my recommendations for a heavy metal detox. To successfully detox from heavy metals like mercury, you should increase your intake of vitamin C foods, green leafy vegetables and cilantro. Cilantro is actually one of the best herb choices when it comes to heavy metal detox.
Chelation Therapy
Chelation therapy is another option when it comes to heavy metal detox. First developed and used in the 1950s for the treatment of heavy metal poisoning, chelation therapy using ethylenediaminetetraacetic acid (EDTA) is now performed to remove common heavy metals, including lead, mercury, copper, iron, arsenic, aluminum and calcium.
Chelation therapy involves a chemical solution called EDTA, which is administered into the body — usually directly injected into the bloodstream — so it can bind with excess minerals. Once bound to toxins in the body, EDTA helps detox the body of heavy metals by removing them before imbalances and illnesses have the chance to develop.
Use Milk Thistle
While you want to stay away from questionable herbal remedies that are high in mercury, there are certain herbal remedies that can really help with reducing your mercury levels. Milk thistle, for example, has been proven effective in supporting the body’s detoxification from heavy metals. The active ingredient in it is called silymarin, and it has incredible cleansing effects on the liver and gallbladder, which can help your body more effectively heal from mercury poisoning.
Keep Things Moving
It’s very essential to heavy metal detox to make sure you have regular (at least daily) bowel movements. This is important so you don’t reabsorb mercury that your body is trying to get rid of as soon as possible. By eating a high-fiber diet, drinking enough water and regularly exercising, you can avoid constipation and keep one of your best natural detoxification processes on track.
Increase Probiotics
In 2012, a group of researches looked at the effects of probiotics on people who have been exposed and contaminated by heavy metals like mercury. According to the study, the species of good bacteria known as Lactobacillus, which is present in the human mouth and gut as well as fermented foods, has the ability to bind and detoxify some heavy metals. (17)
You can supplement with Lactobacillus or you can get it from fermented foods like yogurt, kefir and cultured veggies like kimchi. By making this probiotic a regular part of your diet, you can improve your gut health and help your body cleanse itself of mercury poisoning.
Final Thoughts on Mercury Poisoning
Unfortunately, mercury poisoning is a growing health problem, but the good news is that you can decrease your mercury intake and levels starting today. How long does it take for your body to get rid of the mercury? It really depends on how high your levels are, the source(s) of exposure and the efforts you make to rid yourself of this heavy metal. If your exposure has taken place over many years, it will take longer for levels to go down and vice versa — the shorter or less exposure, the shorter your detox time should be.
If you have concerns about your mercury levels, it’s a good idea to see a doctor for testing. It’s especially important for women who are considering becoming pregnant in the near future to know their mercury levels. Some women with high mercury levels or mercury poisoning ideally should put off pregnancy by at least a few months so they can get their mercury levels down before conception.
When it comes to fillings, amalgam fillings are not your only option. Remember that’s up to you to choose your dental treatment so talk with your dentist about available options. It’s also important to choose a dentist who understands your concerns. IAOMT-certified dentists have been trained and tested in the basics of biocompatible dentistry, including the best ways to safely remove amalgam fillings.
Fish are a very healthy source of protein so I’m in no way trying to discourage seafood consumption. You can continue to eat fish — just make better choices that are low in mercury but high in flavor and health benefits.
It may take some time, but stick with these natural remedies for mercury poisoning and you should feel better and live a healthier life in the very near future!