Natural Heavy Metal Detoxification: A Review
Nutrition / Natural Medicine Update No. 46 (March 15, 2017)
with Dr. James Meschino
Research Topic: Natural Heavy Metal Detoxification: A Review
Source: The Scientific World Journal (2013)
The research paper I am citing today was published in the Scientific World Journal in 2013, by Margaret Sears from the Children’s Hospital of Eastern Ontario Research Institute in Ottawa, Canada. The paper is titled, “Chelation: Harnessing and Enhancing Heavy Metal Detoxification – A Review”.
In modern society, we are constantly exposed to heavy metals such as cadmium, lead and mercury. These heavy metals have no essential biochemical roles in our body and can conversely cause us a great deal of harm if they build up to toxic levels. These heavy metals bind to our tissues, create damaging free radicals (oxidative stress), disrupt our endocrine (hormonal system) and interfere with the absorption and function of important minerals such as magnesium and zinc. Cadmium is classified as a possible carcinogen. Lead can damage the nervous system and be particularly harmful to the developing brains of young children. Mercury is also known to damage the brain and nervous system, and there is an increasing number of people being affected by its bioaccumulation in the food chain, especially in regards to fish and seafood consumption.
As such, the FDA and EPA have developed guidelines about eating fish and seafood to help reduce the risk of serious mercury accumulation and nervous system damage in our bodies. Nevertheless, all of us ingest a certain amount, to some extent, of mercury and other heavy metals like cadmium and lead on a regular basis. The good news is, in addition to working to reduce our exposure and intake of these toxic metals, there are some natural things we can do to help remove, or detoxify and eliminate, some of the heavy metals already in our body, and block the absorption of some heavy metals from our intestinal tract.
So, what natural things can we do to help detoxify these heavy metals and/or block their absorption to some degree? Certain foods that are high in sulfur have been shown to be useful, as heavy metals have an affinity to bind sulfur. Sulfur also makes this heavy metal complex more soluble, enabling the body to more easily eliminate heavy metals in the urine or via the fecal route. Really great sulfur-containing foods are garlic and onions (and the allium vegetables, as they are known) and also the brassica family of vegetables, including broccoli, Brussels sprouts, cabbage, cauliflower, bok choy, and turnips. These are also known as the cruciferous vegetable. These vegetables contain sulfur-containing sulforaphane, as well as indole-3 carbinol, both of which also possess impressive anti-cancer properties. Garlic has prevented cadmium-induced kidney damage and decreased free radical damage due to lead in rat experiments.
Fiber ingested from whole grains and fruits has reduced levels of mercury in the brain and in blood. The use of psyllium husk fiber (the active ingredient in Metamucil) has been shown to block the re-absorption of heavy metals back into the body, once secreted into the gut via the liver and gallbladder, following a meal (this is known as interrupting the enterohepatic circulation). The ingestion of healthy minerals such as calcium, selenium and iron, at optimal nutritional levels, has also been shown to block the absorption of heavy metals into the body. Selenium supplementation is also shown to increase mercury excretion from the body and reduce mercury-induced free radical damage, in a study of 103 mercury exposed villagers. Calcium is known to help block the absorption of cadmium and has reduced lead mobilization from the bones of women during their pregnancy and period of lactation. In children, nutritional iron has blunted lead accumulation. In addition, certain dietary supplements can be helpful as heavy metal detoxifiers.
It is well documented that the mini-protein known as glutathione helps remove heavy metals from body tissues and excrete them from the body. Our bodies naturally make glutathione from the ingestion of three amino acids found in food (glutamic acid, cysteine, and glycine). The problem is, much of our glutathione gets used up by acting as an antioxidant in our cells, and as a conjugating agent for various substances (including acetaminophen) in the detoxification of a variety of agents. This often leaves an insufficient amount of glutathione available to maximize its heavy metal detoxifying function.
However, studies suggest that we can optimize our glutathione status by taking a supplement that boosts glutathione synthesis. These ingredients include alpha-lipoic acid, N-acetyl cysteine, L-glutamine and milk thistle, which contain a glutathione-raising flavonoid known as silymarin. Taking glutathione in its preformed state has not been shown to be useful, as it is poorly absorbed from the gut. However, supplementing with these glutathione-boosting agents appears to be a good way to help optimize glutathione status and thus heavy metal detoxification. In fact, alpha-lipoic acid has its own heavy metal detoxifying properties, over and above its role in raising glutathione. N-acetyl cysteine also has its own unique heavy metal detoxifying properties. So, I really like the combination of these glutathione precursors, to be taken as a daily supplement, if you are trying to boost heavy metal detoxification.
There are other sulfur-containing amino acids that can also be helpful, which include taurine and methionine. Your body normally has ample methionine if you eat standard protein foods and ingest sufficient amounts of the B-vitamin’s folic acid and vitamin B12. Taurine is the most abundant amino acid in the heart muscle and it may play a key role in helping to prevent congestive heart failure, as it serves a multi-purpose function in the heart muscle. Researchers are still looking into its role in heart health, but it certainly has some detoxification ability regarding heavy metals.
For individuals with serious heavy metal toxicities, doctors can administer intravenous pharmaceutical chelating agents, which help remove various heavy metals from body tissues. But this is not something that is typically done as a standard preventive measure on everyday patients seen in clinical practice.
So, what does a heavy metal prevention and detoxification strategy look like for most of us? Well, first and foremost, do your best to reduce your exposure to heavy metals in the environment and the food you eat. With respect to detoxification of heavy metals, try to regularly consume whole grains and fruits, and at least 5 servings per week of a cruciferous vegetable. Add garlic and onions to the foods you prepare, and possibly consider a fiber supplement containing psyllium husk fiber. As for supplements, I like the idea of a high-potency multiple vitamin and mineral that is enriched with the antioxidants vitamin C, vitamin E, and selenium, which help to preserve and/or raise glutathione levels.
With respect to calcium, using a multiple vitamin supplement, or an additional calcium supplement, plus the food you eat each day, you should aim for at least 1,000 mg of calcium per day, and in many cases, more optimally between 1,200 and 1,500 mg per day. As for selenium, a good multiple vitamin supplement should contain 100-200 mcg of selenium. That is plenty. Taking a multiple vitamin supplement can also help ensure more optimal intake of folic acid and vitamin B12 to help optimize methionine synthesis. And there is some preliminary evidence that a probiotic supplement may also be helpful.
You may want to consider taking a supplement with glutathione boosters and detoxifiers that contains alpha-lipoic acid, N-acetylcysteine, L-glutamate, and Milk thistle – standardized to 80% silymarin content. One last thing, sweating with exercise, or by using a sauna, may be a benefit as well, as toxic metals are also excreted in sweat. So, regular exercise is also a natural detoxifier, along with providing a multitude of other health benefits. Another reason to keep doing aerobic exercise.
Ok, that’s my report for this week. I hope you found it helpful.
I provided the main reference in the text below along with a more in-depth research review paper on mercury, and another on glutathione, for those who are interested.
1. (Main Reference): Sears, S.E., Chelation: Harnessing and Enhancing Heavy Metal Detoxification – A Review. Scientific World Journal, 2013. https://www.hindawi.com/journals/tswj/2013/219840
2. Mercury – https://www.hindawi.com/journals/jeph/2012/460508
4. EPA and Mercury: https://www.epa.gov/mercury/basic-information-about-mercury
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