The People's Perspective on Medicine

Are Your Dietary Supplements Contaminated with Drugs?

Many people believe that the FDA verifies that dietary supplements are pure. A new study asks: are dietary suppelemnts contaminated? Answer: Some are!

The Food and Drug Administration has been testing dietary supplements for years. “From 2007 through 2016, 776 adulterated dietary supplements were identified by the FDA and 146 different dietary supplement companies were implicated.” The FDA sent more than 700 warning letters to such manufacturers because the agency had detected undeclared and potentially harmful drugs in them. One might hope that the FDA would have eliminated all dietary supplements contaminated with drugs. Such is not the case.

A New Study of Dietary Supplements Contaminated with Pharmaceuticals:

California investigators discovered a shocking number of dietary supplement manufacturers have continued to adulterate their products with pharmaceutical ingredients (JAMA Network Open, Oct. 12, 2018). The researchers reviewed the database of Tainted Products Marketed as Dietary Supplements. They found that the majority of such contaminated supplements were being marketed for sexual performance, weight loss or muscle building.

Contaminated with Sildenafil (Viagra):

Approximately 80 percent of these products contained one illicit ingredient; the remaining 20 percent contained two or more hidden drugs. The vast majority of tainted supplements sold for sexual enhancement contained sildenafil or a similar compound. This could be a problem, because sildenafil (also known by its brand name Viagra) can interact in dangerous ways with other medications. Men should not be taking it unknowingly, as this could put them at risk.

Contaminated with Sibutramine:

Many of the contaminated weight loss supplements contained sibutramine or phenolphthalein, drugs that were removed from the US market because of unacceptably risky side effects. Phenolphthalein is a laxative and is considered a carcinogen (Cancer Research, Nov. 1, 1996). The investigators warn that such deliberately adulterated products pose a serious public health risk, both alone and in combination with other medicines a consumer may be taking.

Should You Worry?

We suspect that most of our readers are not taking dietary supplements contaminated with drugs. We just don’t get a lot of questions about dietary supplements sold to enhance sexual performance, build muscle or help with weight loss.

Misleading Headlines?

That has not stopped the headline writers from scaring readers with headlines that dietary supplements could contain steroids, Viagra or something far worse. It’s not surprising.

The authors of the JAMA Network Open article introduced their research this way:

“In the United States, more than 50% of adults consume dietary supplements, fueling a $35 billion industry. Dietary supplements include vitamins, minerals, botanicals, amino acids, and enzymes that according to the US Food and Drug Administration (FDA) are not intended to treat or prevent disease.

“One study found that dietary supplement use was associated with 23 000 emergency department visits and 2000 hospitalizations in the United States each year. Serious adverse events reported with the use of dietary supplements include stroke, acute liver injury, kidney failure, pulmonary embolisms, and death.”

The trouble with this scary introduction is that it implies that all dietary supplements are potentially dangerous. Yet what they were looking for and testing were from the FDA Tainted Supplement database specifically relating to dicey sex enhancers, weight loss products and muscle building agents.

What People’s Pharmacy Readers Care About:

Our readers want to know about vitamin D3, glucosamine and chondroitin, CoEnzyme Q10, turmeric (curcumin), fish oil, probiotics, resveratrol and magnesium. The researchers did not investigate these kinds of dietary supplements. We think they have unnecessarily scared millions of people into thinking that their curcumin or CoQ10 could be contaminated with nasty drugs.

Are Your Dietary Supplements Contaminated with Drugs?

Sadly, the FDA does not test most dietary supplements for contamination. That means you don’t know how pure your vitamin D3 actually is. Ditto for curcumin, CoQ10, alpha lipoic acid, glucosamine, MSM, probiotics or even your multivitamin.

We don’t think you need worry that your supplements might contain drugs. But you have no way of knowing if there are other impurities. You also don’t know if the products contain the active ingredients in the amounts listed on the label.

Since the FDA does not test most dietary supplements sold in the U.S., is there any place you can check? The only lab that we know that tests a wide range of dietary supplements is This is not a free service. An annual subscription is $42. We think that cost is justifiable if you are taking dietary supplements and would like to have some inkling of quality.

We wish the FDA were more vigilant when it comes to dietary supplements. Even when the agency knows that there are contaminated sexual enhancers or weight loss products being sold, it does not appear to be capable of getting them off the market. The bottom line is that that in the U.S. there are no guarantees of safety and purity when it comes to such products.

We welcome your thoughts on dietary supplements.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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I was active 2 years ago contacting Walgreens about the loss of the USP seal of purity on their store branded vitamins; in particular their basic multivitamin. They refused to answer my correspondence. I found out that the third party who made their vitamins in the USA in North Carolina (and provided the USP seal of approval) sold to a Chinese firm. The buyer soon eliminated the USP seal of purity. The USP seal was a consumer’s proof that the product met content and purity best practices. Now, none of the major drugstore’s vitamins provide the USP seal. Consumers need to rise up and demand the USP seal.

I agree with all of the above and also wonder if the three meds I take which are made in India are safe. Who is responsible for checking them?

Scary headlines make me figure they’re trying to get legislation so nobody can buy supplements without prescriptions. I don’t believe half of what they say about medications, surgeries, etc. I’m a firm believer in good health, keep your body moving, eat right.

I have subscribed to Consumer Lab for about 10 years. They analyze off-the-shelf products for the stated content of the vitamin or supplement as well as impurities such as heavy metals or unwanted content. A fairly cautious analysis of the efficacy of these substances, based on the outcome of trials published in journals of research, is also part of what is available for a paid subscription.

While I trust virtually nothing coming out of California, this doesn’t surprise me at all. And, I don’t trust the FDA either…it is far too easy for someone to be hornswaggled by Big Pharma, who undoubtedly controls the medical mafia. It’s not much different than some of the food we eat. I simply am not in the trusting mood anymore when it comes to the established powers in this country.

I don’t understand. Why don’t you trust anything coming out of California?

I would add the CDC & NIH to the list of agencies that support Pharma over us.

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