More than two-thirds of Americans take dietary supplements. The vast majority of consumers – 84% – are confident the products are safe and effective.
They shouldn’t be so confident.
I am professor of pharmaceutical practice at the University of Connecticut. As described in my new post in the Annals of Pharmacotherapy, consumers take real risks if they use dietary supplements that have not been independently verified by reputable outside laboratories.
What are the risks ?
Heavy metals, known to cause cancer, dementia and brittle bonescontaminate many dietary supplements. A study of 121 products found that 5% of them exceeded the daily safe limit for arsenic. Two percent had excess lead, cadmium and aluminum; and 1% had too much mercury. In June 2019the Food and Drug Administration seized 300,000 bottles of dietary supplements because their pills contained excessive levels of lead.
Bacterial and fungal contamination in dietary supplements is not uncommon. In one assessment, the researchers found bacteria in the 138 products they studied. Poisonous mushrooms were also found in many supplements, and the number of many products exceeded the acceptable limits set by the United States Pharmacopoeia. Fungal contamination of dietary supplements was bound severe liver, intestinal and appendicular damage.
From 2017-18, dozens have been hospitalized with salmonella poisoning after ingesting kratom, a highly addictive natural opioid. Thirty-seven of the kratom products studied were contaminated.
Some dietary supplements contain drugs, but the manufacturers do not disclose this information to consumers. Often hidden drugs are experimental and in some cases taken off the market because they are dangerous. Hundreds of weight loss, sexual dysfunction and muscle building products are adulterated with inferior or harmful substances.
Sometimes the weed you are thinking of buying contains little or no active ingredient. From time to time, another grass is replaced.
The consequences for consumers are considerable. When Manufacturers Replaced Weed Stephania tetrandra with Aristolochia fangchi grass in 2000, more than 100 patients developed severe kidney damage; 18 others had kidney or bladder cancer. Although the herb is now banned by the United States, a 2014 survey found Aristolochia fangchi in 20% of Chinese herbal products sold on the internet.
In an assessment of CBD products, only 12.5% of vape liquids, 25% of tinctures, and 45% of oils contained the promised amount of CBD. In most cases, they held much less. A few CBD products contained enough THC to put the user at risk of legal marijuana possession.
Embarrassed by the New York Attorney General’s Office investigation suggesting a generalized and fraudulent under-dosage of active ingredients in food supplements, CVS pharmacies analyzed 1,400 products that it previously sold in its stores. seven percent, or approximately 100 products, have failed, resulting in updates to the supplement information panel or removal of the product from shelves.
What should consumers do?
The Health and Education Act Regarding Dietary Supplements of 1994 allows manufacturers to sell dietary supplements without providing evidence of their quality to the FDA. Instead, it’s up to the FDA to prove a product is unsafe and remove it from the market. This is an incredibly heavy and woefully inadequate order. But that is unlikely to change.
In the meantime, I recommend that consumers not purchase supplements without verification from one of three highly reputable independent laboratories: the aforementioned United States Pharmacopeia, NSF International, and ConsumerLabs.com. The United States Pharmacopeia is an organization that sets benchmarks and quality standards for prescription drugs and food in the United States; NSF International is an independent group that assesses the safety and risks of food, water and consumer products; and ConsumerLabs.com is a company that has started verifying the quality of products for consumers who are paying members. These laboratories conduct a initial analysis then carry out unannounced periodic evaluations of the products; those with the appropriate amount of active ingredient, and without contamination or adulteration, can put the United States Pharmacopeia, NSF and ConsumerLabs.com Seals on their bottles. CVS announced that all products sold in its stores going forward will be required to provide the company with proof of quality. Other major retailers are expected to follow suit.
Some manufacturers perform quality testing and post certificates of analysis on their websites. But the autonomy of the laboratory, and its standards, are often overlooked. Sometimes laboratories may select an inappropriate test method, intentionally or unintentionally. Sometimes they perform the test incorrectly or just make up results.
Because the FDA can’t fully protect you from dietary supplement quality issues — at least not right now — you need to protect yourself. Even if a celebrity or “health guru” recommends a product, that doesn’t mean it’s high quality. Before you put any supplement in your body, demand proof.
Editor’s note: This article has been updated to indicate that NSF International, not the National Science Foundation, assesses the safety and risk of food, water, and consumer products.
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