In the quest for peak performance, many fitness enthusiasts turn to dietary supplements to boost their workout routines. But a recent study reveals a concerning reality: the majority of these supplements may not be what they claim to be.

In fact, researchers found that a staggering 89% of the labels on dietary supplements they analyzed did not accurately list the botanical ingredients. Furthermore, 12% of them included substances prohibited by the Food and Drug Administration (FDA).

This means that the supplement you’re taking to enhance your performance might not only be ineffective but could potentially harm your health. It’s time to take a closer look at what’s really in those bottles.

Scientists versus shady supplement dealers

Dr. Pieter Cohen is an associate professor of medicine at the Cambridge Health Alliance in Massachusetts and the lead researcher of the new study. Cohen is famous in the field for being an outspoken critic of the largely unregulated sports supplement industry.

Over the years, the supplement industry has ballooned to over $55 billion in annual sales from just $4 billion in the mid-1990s. Although we might think of many of these products as relating to health, they are regulated by the FDA as a subcategory of food. What this means in practical terms is that a manufacturer can introduce anything into the market that they deem safe.

Meanwhile, the FDA’s job is to identify products that are causing harm after they’ve been on the market and subsequently ban them. This is a flawed system because consumers face unpredictable risks. Consequently, this situation places the burden on consumers to be extremely cautious about what they put into their bodies. However, most people do not do their due diligence and some may even assume since they are sold openly on the market, these products must be safe.

There are at least 95,000 different dietary supplement products available in the U.S. market right now, and there is no way the FDA can check every one of them. This is why Cohen’s work is so instrumental.

In 2017, the Harvard Medical School researcher published a peer-reviewed study exposing some dietary supplements that contained illegal and potentially dangerous substances. In retaliation, the supplement manufacturer sued him for $200 million. As an interesting side story, Jared Wheat, the wealthy founder of the supplement company in question dreamed up his business while incarcerated for dealing ecstasy.

“I spent a lot of money, but hopefully it will deter others from going out there and making baseless allegations,” Wheat said in a phone interview with STAT from his company’s headquarters in Georgia. His advice to other academics: “Think twice and do better research, knowing you can get sued if you do this.”

Dr. Cohen eventually won the defamation trial in a federal court in Massachusetts, but his ordeal highlights the kind of intimidation tactics and powerful reach that some of these supplement companies command.

Mislabeled supplements can cause heart failure

Luckily for us consumers, Dr. Cohen is relentless. He’s now back with a new study exposing the shady and unprofessional business practices of supplement manufacturers.

Cohen and colleagues scoured the market for products containing specific plant extracts, including methylliberine, halostachine, turkesterone, octopamine, and Rauwolfia vomitoria. They then purchased and analyzed 57 products that claimed to include at least one of these extracts.

The results were alarming. In 40% of the products, one of the stated ingredients was not detected at all. And when the ingredients were present, their quantities varied significantly from what was stated on the label, ranging from a mere 0.02% to a staggering 334%.

“Given these findings, clinicians should advise consumers that supplements listing botanical ingredients with purported stimulant or anabolic effects may not be accurately labeled and may contain FDA-prohibited drugs,” the researchers concluded. 

Even more concerning, 12% of the products contained ingredients prohibited by the FDA. The researchers discovered five different prohibited compounds in their analysis. For instance, one particular product advertising it provides intense, sustained “heat generation” and “metabolic boost” contained four FDA-prohibited ingredients.

Another product, promoted as a “fat burner”, lacked the listed Rauwolfia vomitoria root extract but contained 319 mg of octodrine, a stimulant similar to amphetamine that was withdrawn from the market in the United States in 1946. The standard dose for octodrine is only about 16 mg, meaning this supplement contained 20 times the recommended amount.

“In animal studies, it’s [shown to] increase pumping of blood in the heart and increases blood pressure,” Cohen told UPI, referring to octodrine.

“So that’s probably why someone’s putting it in a sports supplement because it would be expected to have the effect of increasing heart beating and pressure in the body. That’s something that could get very dangerous because exercise itself normally increases blood pressure.

“So you’re giving 10 times the normal dose of a drug, that probably shouldn’t be taken pre-exercise anyway. That’s where the risks are probably the highest.”

Despite his experience with poorly manufactured supplements, the findings proved surprising even for Cohen. He highlighted the fact that these products are openly sold on platforms like Amazon and store shelves, leading consumers to assume that the FDA has ensured their safety — and the implications can be dire.

Dr. Cohen warns that these sports products could potentially cause arrhythmias, disrupting the heart’s rhythm and posing a risk of heart attacks. Moreover, excessive intake of stimulants in these supplements could lead to bleeding strokes if blood pressure rises too high, resulting in brain hemorrhages.

Undisclosed prohibited substances and lack of oversight

In addition to octodrine, the researchers identified several other undisclosed prohibited substances in the analyzed supplements. These substances include oxilofrine, 1,4-dimethylamylamine (1,4-DMAA), and deternol.

Not only are these ingredients banned by the FDA, but they are also prohibited by the World Anti-Doping Association, making their use a violation in various sports organizations. If you’re a professional athlete taking such unregulated supplements, your entire career may be at risk. With the potential for suspensions in professional leagues like the NFL, MLB, NBA, MLS, and NHL, as well as college and high school athletics, the consequences extend far beyond health risks.

The lack of FDA oversight and manufacturers’ noncompliance with regulations are the primary reasons that explain these concerning findings. Dr. Cohen recommends that consumers opt for USP- or NSF-certified products, which have undergone rigorous testing to ensure their quality and accuracy.

“As the work by Cohen et al demonstrates, supplements often do not contain what is advertised or, more concerning, contain ingredients that may not be safe for consumers. This work underscores the need for Congress to take action and increase oversight over supplements marketed and distributed in the United States,” said Dr. Peter Lurie, head of the Center for Science in the Public Interest, who published a comment alongside the new paper.

As you embark on your fitness journey, remember that mislabeled workout supplements can pose significant risks to your health. Don’t fall prey to enticing promises on product labels. Investigate and choose wisely. Your heart will thank you.

The findings appeared in the journal JAMA Network Open.