Evaluating The Health Risks From Dietary Supplements

The Dangers Of Supplement Contamination

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You can eliminate practically all side effects of nutritional supplements due to product adulteration. Here is how.

Contaminated or tainted health supplements basically represent products which are different from what consumers are led to believe when buying them.

Ideally, nutritional supplements only contain safe active ingredients (and safe inactive excipients).

Unfortunately, the incidence is quite high among the available products, especially among discount vitamins and nutritional supplements, where additional, “extraneous” substances are also present... contaminants.

Most supplement impurities pose mainly a danger of chronic (enduring) rather than of acute (immediate) toxicity. For no other reason than that tainted products add to the overall toxic burden of each individual person, making them one of the potentially more pertinent health risks of dietary supplements.

Eliminate this particular health threat by choosing high-quality pure vitamins and supplements (“healthy supplements”).

One Of The More Problematic Health Risks Of Dietary Supplements... Supplement Adulteration

-It's Not What's On The Product Label But What's NOT On The Label You Should Be Worried About

In the articles on the regulation of supplements (see Dietary Supplement Regulation -Is Supplement Quality Assured?; Part 1 of a 3-Part Article on "Exploring The Shady World Of Dietary Supplement Regulation") I explained that weak legislative policies and a lack of dietary supplement enforcement leads to a supplement market permeated with low-quality, ineffective, cheap supplements.

Such inferior products are the result of poor manufacturing standards and a lack of adherence to sound science in the conception of product development.

What are the main outcomes of quality-compromised nutritional supplements due to lax manufacturing standards?

Studies have uncovered that vitamins and health supplements may contain...

● too little of an ingredient as listed on the product label,
● too much of an ingredient as listed on the label,
● contaminants,
● a combination thereof.

In an attempt to prevent their occurrence these drawbacks of sub-standard manufacturing procedures are actually covered specifically, by an amendment to the current core policies of dietary supplement regulation, the cGMP regulations of 2007 (elaborated on at cGMP Regulations -A Guarantee For Supplement Efficacy?; Part 3 of a 3-Part Article on “Exploring the Shady World Of Dietary Supplement Regulation”).

But...

The unfortunate reality is that the FDA is unable, due to a lack of resources, to actively enforce these pivotal rules.

As the authors of one study put it:

“[...] paper-based quality systems are still prone to possible contaminations […].” (de Hon & Coumans, 2007)

It leaves the quality of supplements totally in the hands of the nutritional supplement manufacturers.

In a research paper the investigators expressed their observation of this situation:

“Most patients do not realize the great variability among dietary supplements.” (Gardiner, et al., 2008)

The inadequacies of FDA dietary supplement enforcement of the regulatory policies, together with the fact that the FDA essentially only intervenes after a problem with supplement has become apparent (Jiang, 2009), continues to make this particular dietary supplement safety aspect a tangible concern for consumers.

For example, several research reports (Green, et al., 2001; Van Thuyne, et al., 2006; Geyer, et al., 2008; Hasegawa, et al., 2008; Judkins, et al., 2010; Cohen & Ernst, 2010; Tucker, et al., 2018) attest to the contamination of health supplements (including widely-consumed multivitamin supplements) with steroids, stimulants, prescription drugs, pesticides, heavy metals, bacteria, and so forth.

In one study (Tucker, et al., 2018) over 80% of all the tainted sexual enhancement supplements were laced with sildenafil, which is the active pharmaceutical ingredient in the blockbuster prescription medication “Viagra”! Therefore, based on this and other studies (e.g., Hasegawa, et al., 2008; Cohen & Ernst, 2010), it's quite likely that any type of “functional” sexual effect from taking an herbal or “natural Viagra” supplement or other types of dietary erectile dysfunction supplements is primarily due to pharmaceutical-grade genuine Viagra (or one of its authentic chemical analogues).

Typically, the product categories most significantly affected by adulteration have been weight loss, sexual enhancement, sports enhancement and body building supplements (News & Events -Press Announcements, Dec. 15, 2010, from Official US Government FDA website, accessed Feb. 2011; Cohen, et al., 2014; Tucker, et al., 2018). One study (Tucker, et al., 2018), for instance, reported that over 98% of the impure supplements fell into these 3 classes of products.

Consequently, nutritional merchandise from these categories are among the least safe supplements. Or, historically and currently in the US, if you avoid nutritional supplements out of these 3 product categories –weight loss, sexual enhancement, and body building– you have comparatively a rather small risk of encountering tainted supplements.

The US FDA (Food And Drug Administration), too, documented these occurrences from the health risks of dietary supplements spiked with contaminants:

“FDA: Tainted products marketed as dietary supplements potentially dangerous. […]. In recent years, FDA has alerted consumers to nearly 300 tainted products marketed as dietary supplements and received numerous complaints of injury associated with these products.” (News & Events -Press Announcements, Dec. 15, 2010, from Official US Government FDA website, accessed Feb. 2011)

“FDA Warns Consumers Against Dietary Supplement Containing Undeclared Drug. Product poses safety risk.” (News & Events -Press Announcements, January 27, 2009, from Official U.S Government FDA website, accessed Feb. 2011)

“FDA Warns Consumers to Stop Using Hydroxycut Products. Dietary Supplements Linked to One Death; Pose Risk of Liver Injury.” (News & Events -Press Announcements, May 1, 2009, from Official U.S Government FDA website, accessed Feb. 2011)

“The dietary supplement Vita Breath has been recalled because the product may contain hazardous levels of lead. […]. Vita Breath is manufactured by American Herbal Lab Inc. and marketed at health fairs and on the Internet.” (FDA's MedWatch Safety Alerts: May 2010, from Official U.S Government FDA website, accessed Oct. 2010)

On Dec. 1, 2011, a nutritional supplement manufacturer got in trouble (their products got seized upon a request by the FDA) because of repeated violations as far as dietary supplements and health claims concern, and because the company failed to comply with the cGMP regulations of 2007 (News & Events -FDA News Release, “FDA: U.S. Marshals seize dietary supplements, drugs manufactured by Syntec Inc.”, Dec. 1, 2011, from Official US Government FDA website, accessed Dec. 2011).

On the same day, the owner and the managers of two nutritional supplement companies got sentenced to prison and fined after committing more than one violation of the cGMP regulations (the companies maintained seriously unsanitary manufacturing conditions), as the FDA had uncovered prior through inspections of their facilities (Daniells, 2011).

About a week prior, on Nov. 23, 2011, the FDA notified another rather large nutritional supplement manufacturer that they are barred from selling any more products because the company kept distributing tainted and mislabeled supplements even after they should have legally complied with the 2007 cGMPs regulations by 2010, and because they failed to report serious adverse events in connection with their products (News & Events -FDA News Release, “FDA takes enforcement action against Pennsylvania dietary supplement maker -First permanent injunction of its kind; more than 400 products affected”, Nov. 23, 2011, from Official US Government FDA website, accessed Dec. 2011).

According to data from the FDA this particular supplement company had been distributing contaminated products for many years. One person experienced one of the more serious side effects of dietary supplements, a mild heart attack, after taking the company's adulterated nutritional supplements.

Apart from the problem with adulterated constituents in nutritional supplements, there's the issue that products contain either too little or too much of a listed ingredient...

...despite, and after, the incorporation of the improved FDA cGMPs regulations of 2007.

Here are some media accounts alerting about the problem of inaccurate label claims, impurities, and negative effects of dietary supplements:

“How Does Your Multivitamin Stack Up?-Rating Firm Flunks One-Third of Samples Tested for Purity and Dosage” (The Washington Post, Feb. 20, 2001)

“Last year, a report commissioned by the International Olympic Committee revealed that a quarter of the 600 over-the-counter nutritional supplements that were analyzed contained nonlabeled banned substances that could lead to a positive drug test.” (The New York Times, “U.S. Athletes Must Guess on Supplements”, Jan. 30, 2002)

“Nutritional Supplement Doses Not Always Accurate: Value of Supplements Still Unknown” (American Cancer Society, July 30, 2002)

“Dietary supplements can be risky; Consumer Reports recommends avoiding some” (The Washington Post, Aug. 3, 2010)

In a 2009 article called “Contaminants Lurk In Many ‘Natural’ Products” by the Associated Press it says:

“One quarter of supplements tested by an independent company over the last decade have had some sort of problem.” (Associated Press, 2009)

An outbreak of selenium (trace mineral) toxicity among numerous patients of a chiropractor in 2008 was investigated by officials of various US health department agencies and traced back to a liquid dietary supplement (multi-vitamin-mineral product) containing an overdose of selenium (and chromium), due to poor manufacturing standards (MacFarquhar, et al., 2010).

A study conducted by the US government on a number of herbal products, manufactured by well-known nutritional supplement brands, found that none of the health supplements contained unacceptable levels of heavy metals, but most were contaminated with microbes, such as fungi and bacteria (Raman, et al., 2004).

In an investigative report Pieter Cohen, MD, who authored several papers on quality aspects of nutritional supplements, noted:

“[...] more than 140 contaminated products have been identified, but these represent only a fraction of the contaminated supplements on the market.[...]. A wide range of dietary supplements have been found to be contaminated with toxic plant material, heavy metals, or bacteria. […].” (Cohen, 2009) [emphasis added]

In a study of multivitamin supplements, the independent testing organization found that a third of the products had either too little, or too much, of certain ingredients, or had other labeling issues (Carroll, 2011). Another paper also reported that only 1/3 of the vitamin D supplements evaluated met label potency claims, the rest of the health products either contained too little (as low as 9%) or too much (as high as 146%) of the stated dose (Leblanc, et al., 2013).

Health Risks From Dietary Supplements...

-Are The Ingredients To Blame?

“The real issue of safety resides not in the toxicity of any particular nutrient within a formulation, but rather in the manner in which the final product has been manufactured.” (MacWilliam, 2007)

Overall, active ingredients have a strong history of dietary supplement safety. Simply because they are innate (orthomolecular), essential, “body-friendly” substances for the most part (think vitamins, amino acids, and so forth).

The public is quite aware of these facts. In all likelihood it is why intuitively people don't try to commit suicide with nutritional supplements, even though these health products are readily available, but instead they routinely resort to, and rely on, over-the-counter drugs or other non-body-innate, synthetic substances to end their lives (American Association of Poison Control Centers, 1983-2008).

Apart from improper product use, it's very unlikely you will get seriously injured because of safety issues of the actual supplement ingredients (unless they've been artificially altered as is the case with non-orthomolecular concentrated extracts, which can raise the risk of adverse outcomes -read my report Do Garcinia Cambogia Side Effects Boost Diabetes?). The very low rate of moderate to serious vitamin side effects and side effects of dietary supplements in general is testimony of that.

As pointed out what is a more serious threat, one of the more worrisome health risks of dietary supplements, are contaminants.

In the US, there are currently no requirements to label GMO (=genetically modified organism) or GE (=genetically engineered) foods. This means, for example, that nutritional supplements could be legally produced using GMO in their manufacturing.

Extensive data about one of the most well-known disasters of supplement contamination supports the view that GMO product adulteration was the likely cause. This source of supplement contamination still hasn't been (sufficiently) remedied (explained in my article L-Tryptophan: The Truth About The FDA Tryptophan Recall Of 1989).

Impurities can be found among active and potentially also among “inactive” ingredients, known as excipients, of a nutritional supplement. In actually they are not inert or inactive in the truest sense of the words because they exert very specific functionalities (Pifferi & Restani, 2003). Excipients are additives, fillers, coating agents, lubricants, flavors, preservatives (antioxidants), and binders. They are tiny amounts of substances mixed in with the actual active ingredients to assure consistency of product quality. For instance, excipients help that the supplement gets dissolved and absorbed in an uniform manner, prevent the clumping together of active ingredients, and prevent that a product falls apart prematurely.

Contaminants such as heavy metals and formaldehyde have been found in excipients commonly used in nutritional supplements (Crowley & Martini, 2001). Numerous death occurred over the years because of adulterated excipients (Gebhart, 1997; Pifferi & Restani, 2003).

Furthermore, contaminants can not only interact with the active ingredients of a nutritional supplement but may also with “inert” excipients of a product.

The available data on excipients, however, indicates that by and large:

“Adverse effects due to excipients are, fortunately, infrequent and mild, because excipients are generally selected because of their low toxicity.” (Pifferi & Restani, 2003)

In brief...

The predicament is such that on numerous occasions negative effects of nutritional supplements are not caused by the ingredients but by impurities, making food supplements predominantly “guilty by association”.

Dietary Supplement Dangers...

-Should Product Contamination Be A Concern For You?

“The expanding body of scientific research in epigenetics, environmental health, and molecular medicine verifies what medical history has repeatedly and consistently confirmed—that deficiency and toxicity states cause disease.” (Stephen J. Genuis, MD, in 2011)

The contamination health risks with dietary supplements should probably be a real concern for you.

Certain impurities, such as steroid and prescription drugs, could interact in harmful ways with other pharmaceutical medications (Tucker, et al., 2018) or certain supplement ingredients [see "Facts About Dietary Supplements: Supplement-Drug Interactions" (Drug Interactions With Nutritional Supplements –Real Or Exaggerated?) –direct link to it at the end of this article under Recommended next pages].

Other contaminants such as microbes could trigger acute toxic dietary supplement side effects.

However, of much greater significance and worry, as far as product contamination goes, lies quite conceivably in the long-term and not so much in the short term.

The situation is such that consumers usually take supplements on a daily basis over a long period of time, oftentimes for many years.

Receiving tiny amounts of contaminants (like heavy metals, prescription drugs, noxious microbes, or synthetic pesticides, for example) over such lengths of time will add up, especially because some of these impurities tend to get stored in fatty tissues. This increases the toxic load and raises the toxicity potential, and can directly contribute to serious health problems which may not show up immediately or intermediately. The mixing of contaminants raises the level of toxicity too, possibly exponentially.

The US government alluded to these facts when it stated:

“When consumed in high enough amounts, for a long enough time, or in combination with certain other substances, all chemicals can be toxic, [...]. (Official US Government FDA website, accessed Oct. 2011) [emphasis added]

The water, the air, the soil, the food, common consumer products... all is polluted, to one degree or another, with all kinds of toxic compounds (Environmental Working Group, 2005). No wonder dozens, even hundreds, of man-made substances, such as synthetic pesticides, are found even in fetuses and newborns (Covaci, et al., 2002; Environmental Working Group, 2005; Genuis, 2009 & July 2011). Another smaller-scale test detected hundreds of harmful chemicals also in adults (Environmental Working Group, 2005).

Many of these pollutants, particularly in combination and at toxic levels, lead to neurological problems, damage to the immune system, liver dysfunction, hormone disruption, deleterious cellular and genetic impact, allergy promotion, can cause DNA damage (Perera, et al., 2002) which could lead to cancer and a host of other health issues (National Toxicology Program, 2010; Genuis, Jan. 2011).

The problem of contamination or xenochemical exposure may be intensified by the fact that certain substances, such as estrogen and hormone-activating chemicals (endocrine disruptors) like phthalates, Bisphenol A and some pesticides are more toxic at smaller doses than at larger doses, contrary to the linear monotonic dose-response curve commonly and universally assumed to be correct by authorities of toxicology, meaning there could be large effects from small doses (Andrade, et al., 2006; Myers & Hessler, 2007).

Bottom line?

The health risks of dietary supplements are enhanced if the products are adulterated.

Because...

All harmful contaminants, including the ones contained in nutritional supplements, add to the toxic burden of an individual, thereby increasing the overall risk of disease.

Therefore, compelling research data indicates that it is very prudent, for the sake of your own health, to avoid contaminants if at all possible.

Tainted Supplements & The Analogy To Food... Sort Of...

The health risks of dietary supplements regarding contaminants are fairly analogous to eating food. Or more exactly, to the choice you make between eating organic versus non-organic food.

Non-organic (lower-quality) food contains various impurities and contaminants, such as synthetic pesticides, heavy metals, PCBs, and other poisons. Most nutritional supplements are of low-to-mediocre quality. A number of them are poisoned with pollutants.

Organic (higher-quality) food contains none or few impurities such as synthetic pesticides. Similarly and probably even superior to organic food, high-quality, pure vitamins and health supplements are (largely) free of contaminants.

In certain areas of your life you have control (or more control) over exposure to toxins in a widely polluted world.

For example, by choosing to eat organic food, by choosing to filter the water you drink, by storing food in glass and not plastic containers, by choosing to buy safe toxic-free consumer and household products, and... when you buy dietary supplements to choose high-quality pure vitamins and health supplements you will lessen your personal toxic burden.

Furthermore, ingredients of wholesome food and science-based, top-quality vitamins and health supplements also directly protect against many poisons and pollutants, both from natural as well as synthetic sources.

Plant-based food (vegetables and fruits) contains dozens to hundreds of natural pesticides (Ames, et al., 1990, Pgs. 7777-81). Therefore, an individual ingest per average day a much larger quantity of them than of synthetic pesticides (Ames, et al., 1990, Pgs. 7777-81). Many or most of the natural pesticides, akin to the synthetic types, are also toxic at high levels (Ames, et al., 1990, Pgs. 7777-81).

However, plant foods contain many remarkable protective substances against these potential poisons, such as vitamins, bioflavonoids, and antioxidants, rendering commonly consumed vegetables and fruits strongly health-beneficial overall (Ames, et al., 1990, Pgs. 7777-81; Dragsted, et al., 1993; Weiner, 1994; McCullough, et al., 2012).

Of most importance...

The protective substances in fruits and vegetables apparently are similarly effective against the poisonous effects of synthetic pesticides (Ames, et al., 1990, Pgs. 7782-6), and other types of toxins.

For example, cadmium, a poisonous heavy metal widely encountered in the food supply, had been reported to raise the risk of breast cancer (Julin, et al., 2012). Yet, while the toxin is most commonly found in vegetables and grains, the women who consumed the largest amount of those foods had the lowest breast cancer risk, presumably due to anticarcinogenic effects of phytochemicals/bioflavonoids (Julin, et al., 2012).

Yet...

While there is evidence that a highly predominant plant-based diet can lead to health issues, such as infertility, there is ample evidence that (prolonged) synthetic chemical exposure very significantly increases the risk of many types of diseases (Colborn, et al., 1996).

Mainly because xenochemicals, such as synthetic pesticides, tend to accumulate inside the human body, while natural pesticides, such as phytoestrogens and other substances commonly found in plant food, get excreted quickly (Colborn, et al., 1996; Zava, et al., 1997).

As a result, many chronic degenerative diseases, such as cancer and heart disease, are strongly related to the influence of synthetic man-made chemicals (e.g., tobacco smoking, environmental pollutants) and medical procedures (e.g., medical uses of ionizing radiation –see my Mammography Myth book).

Product and service industries (and capitalist-corporate governments), however, commonly downplay the harmful effects of their commodities to protect their prime focus... profits.

So, while the incorporation of adequate plant food and well-designed nutritional supplements is of critical urgency, the proactive avoidance of synthetic chemicals, such as pesticides, xenoestrogens, medical x-rays, is likely similarly essential.

Dietary Supplements And Risks Of Contamination...

-How Can You Eliminate The Threat?

Partly because the global supply chain of raw ingredients for nutritional supplement has become increasingly complex, the opportunities for product adulteration has also risen (Shao, 2010).

By using only high-quality, science-based, pure vitamins and supplements in a responsible and proper manner from dependable nutritional supplement manufacturers, you can practically prevent all side effects of dietary supplements.

In brief, this method of supplementation eliminates virtually all health risks from dietary supplements.


(Originally published: ca. July-2012 | This is a revised version)

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Recommended next page(s):
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• Tougher Supplement Regulation: A Necessity Or Politics?
  

• Facts About Dietary Supplements: Supplement-Drug Interactions
  

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Article Index On Health Risks
From Dietary Supplements
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• Side Effects Of Dietary Supplements -The Dangers Of Supplements!
• Health Risks Of Dietary Supplements -The Proper Perspective
• Side Effects Of Dietary Supplements -Top 10 Tips To Avoid Them

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