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Heavy Metal Hysteria

(2014-02-17 06:45:38) 下一个

It seems that heavy metal hysteria is reaching an all-time high in the alternative health community--especially since Mike Adams at Natural News published a newsletter attacking "high" levels of heavy metals in brown rice protein products--a newsletter that he quickly replaced with a softer version, but not before readers freaked out.

How justified is this hysteria? Are heavy metals as dangerous as claimed? How much of what's being said is actually true? Is rice protein to be avoided? Is whey a better alternative than rice protein?

What are Heavy Metals?

Well, here's the first surprise: there is no standard definition for the term "heavy metals"!

In fact, heavy metals are part of a loosely defined group of elements that exhibit metallic properties and that have a high atomic number or atomic weight and a specific gravity greater than 5.0. Beyond that, many different definitions have been proposed--some based on density, some on atomic number or atomic weight, and some on chemical properties--but none have stuck. The IUPAC (International Union of Pure and Applied Chemistry) actually issued a technical report in which they called the term heavy metal a "misinterpretation due to all of the contradictory definitions and its lack of a coherent scientific basis."

And then there's the question of toxicity…also not cut and dried.

Although excessive levels can be damaging to living organisms, human beings nevertheless require varying amounts of some "heavy metals" such as iron, cobalt, copper, manganese, molybdenum, and zinc to survive. Other heavy metals such as mercury, plutonium, and lead are toxic with no biological redeeming value, and their accumulation over time in the bodies of animals can cause serious illness.

In truth, when people in the alternative health community talk about "heavy metals" they are really talking about "toxic metals." Unfortunately, even this term has no exact definition, and even worse, the issue of toxicity itself is not an absolute. Certain elements that are normally considered toxic are, for certain organisms, or under certain conditions, beneficial. Examples include vanadium, tungsten, and even cadmium. And for that matter, you would be hard pressed to find anyone who has anything nice to say about arsenic, and yet, as we will explore in more detail a bit later, small amounts of arsenic appear to be necessary for both growth and reproduction. And even tungsten, which was singled out in the Natural News report may hold a surprise or two itself.

A Gram of Heavy Metals is not Necessarily a Gram of Heavy Metals

Gertrude Stein said, "A rose is a rose is a rose." Well, that may be true of roses, but it's not literally true when comparing the amounts of heavy metals in various items. As I explained back in 2011 when talking about Dr Oz's big announcement concerning arsenic in apple juice, it matters a great deal as to whether or not the heavy metal is present in an organic or inorganic form. As the FDA itself states, "The inorganic forms of arsenic are the harmful forms, while the organic forms of arsenic are essentially harmless." What the heck are they talking about? What does it mean? And in what alternate universe does the FDA promote the "virtues" of organic?

In order to understand the issue here, we need to define the word organic, but once again, that's not as simple as it might seem. Most people probably think it means something like.

  • Grown on an organic farm with fertilizers and/or pesticides that are strictly of animal or vegetable origin.
  • Or raised without the use of drugs, hormones, or synthetic chemicals -- as in organic chicken.
  • Or maybe, as found in nature as opposed to being produced in a secret government lab.

And those are all valid definitions. However, they are not the only definitions. For example, the use of the word organic in the term "organic chemistry" has a very different meaning. The "organic" in organic chemistry refers to the branch of chemistry concerned with carbon compounds--other than a handful of compounds such as carbon monoxide and carbon dioxide. Originally, this definition was confined to compounds produced by living organisms but now extends to include man-made substances based on carbon, such as plastics.

And then there's the definition of organic as the FDA is using it in their statement above. It has nothing to do with food and nothing to do with how things are grown. It is, however, connected to organic chemistry. To clarify, arsenic is (as are all heavy metals) a naturally occurring element widely distributed in the earth's crust, in the oceans, and in most plant and animal matter. In the environment, arsenic is combined with oxygen, chlorine, and sulfur to form "inorganic" arsenic compounds. These are the highly toxic forms of arsenic that the FDA referred to and that are both poisonous and carcinogenic. But in animals and plants, arsenic combines with carbon and hydrogen to form "organic" arsenic compounds, which are far less toxic. Why are the organic forms less toxic?

The toxicity of arsenic primarily depends on its valence state -- its proclivity for bonding with other molecules. Or to put it another way, the more a particular arsenic compound likes to bond, the more likely it is to lock onto human tissue and biological molecules, disrupting enzyme reactions and breaking down the high energy bonds in key molecules such as ATP. Most inorganic forms of arsenic are highly active and readily bond with molecules in the human body. In other words, the more likely it is that those forms are toxic. Organic arsenic molecules such as arsenobetaine and arsenocholine, on the other hand, have little tendency to bond with human tissue and are rapidly excreted in unchanged form in the urine -- thus making them relatively nontoxic.

To put this in simple English: you're far better off with a food that contains 50 ppb of organic arsenic than one that contains 10 ppb of inorganic arsenic. Unfortunately, you can't tell which is which simply by comparing numbers in a table.

Beginning to make sense?

As mentioned earlier, the FDA recommends keeping arsenic levels in drinking water below 10 parts per billion. But in drinking water, we're generally talking about inorganic arsenic absorbed from underground rocks.  In fact, because arsenic is so omnipresent in the soil and ocean water, the average person consumes, on average, about 10-50 millionths of a gram of arsenic a day, with over two thirds of that coming from organic sources. And in truth, levels of 1,000 micrograms are not unusual following consumption of fish or mushrooms. But again, there is little danger from these sources because these are organic arsenic compounds and are essentially non-toxic.

And then there's the issue of whether the heavy metal is "bound" or "unbound." If the metal is in the soil where the plant grows, then it is incorporated into the interstitial tissue of the plant itself. As such, it is "bound" to the plant and not readily absorbed by the body and tends to pass through unabsorbed in the stool. On the other hand, if the heavy metal is environmental (that is, deposited on the plant as the result of air or rain pollution or as the result of pesticide spraying, then it is not part of the plant itself. It is unbound and is much more readily absorbed by the body after consumption. (Note: heavy metals found in animal foods--i.e. meat, fish, dairy--tend to be predominantly unbound since they are the result of the regular consumption of unbound heavy metals over the life of the animal.) How much of a difference does binding make? Bound lead has an absorption rate of about 20% and bound cadmium averages about a two to six percent absorption rate. This makes a vast difference when looking at test results for heavy metals in a rice protein VS drinking water, or dairy protein for that matter. The numbers may look the same, but in terms of what actually gets absorbed by the body, they are vastly different.

Consider the fact that the Japanese diet includes a high consumption of rice, a symbolic staple of the Japanese diet, and yet the Japanese rank number two in all the world for overall life expectancy, trailing only Monaco.1 Also, when it comes to Alzheimer's (since brain damage is associated with heavy metal consumption), Japan also ranks well, placing near the bottom of the list (the further down  you are on this list the better), with a mortality rate from Alzheimer's about 1/10 that of the US.2 Incidentally, Finland, Iceland, and the US top the list…and Monaco once again comes out best, placing at the very bottom of the list with a statistical zero percent incidence rate. It will be interesting to see what the future holds, as the consumption of rice in Japan has been dropping over the last several decades as bread, pasta, and other wheat-based products have grown in popularity. In any case, in the real world over the entire existence of modern man, the high consumption of rice with its organic and bound heavy metal content has had virtually no impact on either mortality or brain health. Keep in mind: that's the real world, not theory.

Toxins in everything

When we mentioned that heavy metals are present in virtually all the earth's soil and ocean water, we touched on a second very, very important concept: it's tough to avoid heavy metals. They are present in all the soils of the world and in all its oceans. Take arsenic again as an example. It's actually the 20th most abundant element out of 90 naturally occurring elements. The earth itself contains an astounding 1.8 mg of arsenic per kilogram. That may not sound like a lot…until you consider that the earth weighs some 6.6 sextillion tons. Multiply that out, and it's a whole lot of arsenic. And the ocean is even worse, with concentrations of arsenic reaching double that found on land, or about 3.7 mg per liter. What that means is that anything that grows on the land or lives in the ocean is going to contain arsenic, not to mention all of the other heavy metals -- and anything that eats anything that grows on the land or lives in the ocean is going to pick up some of those heavy metals. Yes, the amounts will vary from location to location. Some areas are higher in one heavy metal and less in another. When testing, you need to do a full panel to get a complete story.

In other words, heavy metals are unavoidable in the diet. Everyone has some daily exposure to them because they are found everywhere -- in water, soil, house dust, air, and food. And less is certanly better than more. But the good news is, as we've already discussed, that plants absorb a lot of this inorganic arsenic and convert it to organic forms or bind it to the plant matter itself. That means that the majority of our exposure to heavy metals, at least through plant based foods, is not usually considered harmful unless at extremely high levels consumed over a long period of time. Inorganic and unbound heavy metals that come from air pollution or are sprayed on foods as a pesticide or consumed in meat, fish, and dairy are a different story.

Toxic Heavy Metals Are Sometimes Essential Nutrients

And there's another surprise in the equation: despite the fact that inorganic arsenic is a deadly poison, it is also an essential trace element in its organic form, essential for health and even life -- although the necessary intake may be as low as 0.01 mg/day.

Studies of animals such as chickens, rats, goats and pigs show that small levels of organic arsenic are most likely necessary for proper growth and reproduction. In these studies, the main symptom of not getting enough arsenic was retarded growth and development.3 Initial studies on arsenic deprivation in animals have shown that arsenic, in very small quantities, may have a physiologic role in the metabolism of the sulfur-containing amino acids, methionine and cysteine.4

And in fact, the same can be said to be true for several other "deadly" elements including vanadium, aluminum, and even strontium.5 (We'll talk more about aluminum in a moment.) That said, you don't want to consume more arsenic in any form (or any of the other "toxic" metals for that matter) than you have to. This becomes a problem when you consider that inorganic arsenic is used in great abundance in many countries in insecticides (outside the US), poisons, and weed killers. The same is true for most of the so called toxic heavy metals as they are heavily used in industry. This added exposure ups the ante. Essential trace elements are "essential" only when they enter the body in trace amounts and in their organic or bound forms.

Aluminum and Fluorine

Aluminum, although not technically a heavy metal, is often considered one when it comes to health. It is one of the most abundant minerals on earth, and represents about 12% of the earth's crust. And even more so than arsenic, it is found in large biological quantities in every plant, animal, and human. At higher levels, and in an inorganic form, aluminum is considered toxic and is associated with cognitive disorders such as dementia and Alzheimer's disease. But at trace levels, organic or bound aluminum may be essential to life through its action on a small number of enzymes such as succinic dehydrogenase and d-aminolevulinate dehydratase. Succinic dehydrogenase6 removes hydrogen from compounds so that they can then be oxidized (essential for the survival of infants), and d-aminolevulinate dehydratase is involved in porphyrin synthesis (essential for the manufacturing of hemoglobin in your blood). Foods naturally high in organic aluminum include peppermint, spearmint, and bananas.

Fluorine is another "toxin" that is essential for health -- but only at trace levels and only in its organic form. The organic form of fluorine combines with calcium (when in the presence of molybdenum) to form calcium fluorapatite, which is an essential component of healthy teeth and bones. Organic fluorine is present in tiny amounts in most foods, but is particularly abundant in tea and some seafood. Unfortunately, while the FDA is now asserting the health differences between organic and inorganic arsenic, they have not chosen to make the same distinction when it comes to fluorine, which means that many people are now saturated with inorganic fluoride in their toothpastes and drinking water. Unlike organic fluorine, inorganic fluoride does not contribute to bone and tooth health (it actually creates brittle bones and teeth) and readily causes fluoride poisoning at even very small doses.

And Then There's Tungsten

In his article on brown rice protein, Mike Adams singled out tungsten as a heavy metal found in rice protein for special concern, but was hard pressed to delineate any specific health consequences from tungsten found in minute levels in food. In the end, the warning amounted to "be concerned just because it's a heavy metal." And there's a reason for that lack of specificity. Quite simply, tungsten plays no biological role in multi-celled organisms (it is used by some bacteria), so any tungsten present in food, unless at extremely high levels or, more specifically inhaled, is harmless and quickly passes from the body. It is simply not part of any biological processes and is not used by the human body. In other words, its presence at low levels is biologically irrelevant.

The safe level of 50 ppb cited by Natural News is completely arbitrary. It is not based on any science. Tungsten is not even on the Prop 65 list, the most anally restrictive toxicity list out there.

That said, it's certainly an interesting commentary that a study published in Free Radical Biology and Medicine found that small amounts of tungsten have proven to be effective in reducing the formation of arterial plaques. In control groups of mice fed a non-Western-type diet, very little arterial plaque formed. On the other hand, for mice fed a Western-type diet much more plaque was seem. But those levels of plaque were reduced when mice were treated with tungstate (a biologically active, tungsten-based compound). So tungsten turns out to be effective in preventing plaque formation. Not bad for a "heavy metal. " But how can this be? How can a so called toxic metal have any possible health benefits? As it turns out, tungstate inhibits xanthine oxidase activity (something we talked about years ago when discussing homogenized milk) and so diminishes the formation of peroxide which plays a key role in plaque formation and fatty deposits. The effect of tungstate on plaque formation is dramatic.7  

Again, it's worth noting that no health problems have been associated with the low levels of tungsten found in food. In fact, it's a good thing that there are no indications that it presents any sort of problem when found in food at normal levels since tungsten is, as are virtually all heavy metals, present in minute amounts in pretty much every food that comes from the sea or is grown on the land. Only hydroponically grown foods or foods in which it is processed out can avoid it. That said, it should be mentioned that hydroponically grown foods, although they tend to be "cleaner," are also far more likely to be devoid of essential trace minerals. And when it comes to protein sources, whey, which processes out a number of heavy metals such as cadmium, lead, and tungsten, presents its own problems since it contains two of the most allergenic compounds found in food (beta-lactoglobulin and alpha-lactalbumin), in addition to being associated with the development of aminoacidemia. And finally, it's also worth noting that radioactive cesium and strontium 90 (the radioactive form of strontium), which are both considered toxic heavy metals, collect in liquid dairy whey and are then concentrated several times over when turned into powdered whey concentrate.8 And for those worried about radioactivity from Fukushima making its way across the world and into the food chain, that's a point of concern.

Conclusion: Rice Protein Is Safe

In the end, the issue isn't really about overstated trace amounts of arsenic, lead, cadmium, mercury, and tungsten in rice protein, or even strontium 90 and cesium in whey. As we've seen, the story on heavy metals can't be reduced to a simplistic media headline or even a simple listing of parts per billion in a table.

  • Far from being toxic, at low trace levels, many heavy metals are essential.
  • There is a huge difference in how the organic forms and the inorganic forms of all these elements behave in the body. As the FDA says for arsenic, "Organic good. Inorganic bad."
  • Bound and unbound heavy metals are also absorbed at very different rates in the human body despite reading as identical in a lab test. In other words, a gram is not a gram is not necessarily a gram.
  • And even if you want to totally avoid them, you can't. It's impossible. They're everywhere -- in every plant, in every animal. The levels vary, of course, from plant to plant and from animal to animal. One may be higher in lead, another in cesium. You just want to minimize your exposure to the inorganic and unbound forms.
    • And if you're concerned about them, you can always do a periodic heavy metal detox. Look for a formula based on cilantro and chlorella. Together, these herbs create a powerful oral chelation formula.
    • Incidentally, Natural News, almost a year ago to the day, took on the issue of heavy metals in chlorella. If you think about this for just a moment, it shouldn't be that surprising. Chelators such as chlorella, clay, and humic/fulvic acid, by definition, are going to "pick up" heavy metals in their natural environment. They wouldn't be very much use as chelators if they didn't. But that doesn't mean they will then release those heavy metals back into your body when you consume them. In fact, quite the opposite happens. They tightly hold onto the heavy metals they have already captured (releasing none into your body) and then proceed to capture those heavy metals floating around in your body. Think of it like a sponge that has a little water already in it. When you drop that sponge in a bowl of water, it's not going to add that water to the bowl, but rather it's going to suck the water up in the bowl. Obviously, the lower the heavy metal content in the chelator when you ingest it, the more it can remove from your body, but that's a story for another day.
  • In summary, don't have a knee jerk reaction to the label "heavy metals." (Both calcium and iron are technically heavy metals.) Yes, obviously, when it comes to "toxic" heavy metals, less is better than more. But the issue is far more nuanced than a simple label--or even numbers on a chart for that matter. You have to factor in whether or not the element actually has any "proven" toxicity (tungsten has no demonstrated toxicity), whether it's organic or inorganic (organic arsenic is virtually ignored by the body), and whether it's bound or unbound (bound cadmium has only 2-6% absorbability).  

 

You should feel safe using any quality rice protein product from companies you know and trust in regard to heavy metals. (I'd have less confidence in low cost generic brands where ingredient sourcing is likely to be an issue.) That said, there is no historical indication of any kind that rice products from anywhere in the world will shorten your life expectancy or harm your brain in any way. In fact, as we've discussed already, the statistical evidence over the centuries is quite the contrary. The bottom line is that brown rice protein combined with yellow pea protein is still my personal choice as a protein supplement over both whey and soy. I like hemp protein too, but the taste, at least so far, is much less user friendly.

  • 1. "Life Expectancy by Country." World Health Organization. (Accessed 10 Feb 2014.) http://apps.who.int/gho/data/node.main.688?lang=en
  • 2. "World Health Rankings: Alzheimers/Dementia." WorldHealthRankings. (Accessed 10 Feb 2014.) http://www.worldlifeexpectancy.com/cause-of-death/alzheimers-dementia/by-country/
  • 3. Uthus EO. (Chappell WR, Abernathy CO, and Cothern CR, eds.) "Arsenic essentiality and factors affecting its importance. In: Arsenic Exposure and Health." Northwood: Science and Technology Letters, 199-208, 1994
  • 4. Eric O. Uthus. "Arsenic essentiality: A role affecting methionine metabolism." The Journal of Trace Elements in Experimental Medicine. Volume 16, Issue 4, pages 345--355, 2003.  http://onlinelibrary.wiley.com/doi/10.1002/jtra.10044/abstract
  • 5. S. Pors Nielsen. "The biological role of strontium." Bone. Volume 35, Issue 3 , Pages 583-588, September 2004. http://www.thebonejournal.com/article/S8756-3282(04)00181-4/abstract
  • 6. B. L. Horecker, Elmer Stotz, and T. R. Hogness. "The Promoting Effect Of Aluminum, Chromium And The Rare Earths In The Succinic Dehydrogenase-Cytochrome System." From the George Herbert Jones Chemical Laboratory of the University of Chicago, Chicago. Received for publication, November 28, 1938. http://www.jbc.org/content/128/1/251.full.pdf
  • 7. Schröder K, Vecchione C, Jung O, Schreiber JG, Shiri-Sverdlov R, van Gorp PJ, Busse R, Brandes RP. "Xanthine oxidase inhibitor tungsten prevents the development of atherosclerosis in ApoE knockout mice fed a Western-type diet." Free Radic Biol Med. 2006 Nov 1;41(9):1353-60. Epub 2006 Apr 4. http://www.ncbi.nlm.nih.gov/pubmed/17023262
  • 8. Tomoko Otake. "Hold the cesium: Ways to reduce radiation in your diet." Sep 20, 2011. The Japan Times. (Accessed 10 Feb 2014.) http://www.japantimes.co.jp/life/2011/09/20/life/hold-the-cesium-ways-to-reduce-radiation-in-your-diet/#.UvlgiNGPKbg

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