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Scientists are finding that many "all-natural" dietary supplements contain potent drugs

Why a concerned group of academics and public officials are exposing the evils of dietary supplements.

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Ten years ago, when Pieter Cohen was working as a physician in Somerville, Massachusetts, he started to notice a trend among his patients: some of them were coming into his clinic with unexplained liver failure, kidney failure, panic attacks, and palpitations. Doctors couldn't figure out what was going on.

So Cohen, a professor at Harvard Medical School, did a little digging around and soon discovered that these illnesses seemed to be linked to rainbow diet pills: weight-loss supplements and powders that were coming into the United States from Brazil. Cohen analyzed the contents of the pills and found out that they often contained antidepressants and thyroid hormones, among other pharmaceuticals.

This was stunning. Dietary supplements are lightly regulated by the Food and Drug Administration precisely because they're not supposed to contain prescription-strength pharmaceuticals — these supplements are deemed "natural" and get the same oversight that food does. And yet, over and over again, Cohen and his colleagues have analyzed popular supplements and found that they often contain powerful drugs and other disturbing ingredients that consumers would never expect from simply reading the packaging.

"We’ve found that potent drugs are often masquerading as natural extracts," Cohen told me. In nine subsequent studies, Cohen and his chemist co-authors have discovered that many botanical supplements actually contain prescription-strength drugs, or drugs banned by the FDA, or even drugs that have never been tested in humans.

Cohen is part of a group of academics and public officials who are trying to expose and crack down on the dietary supplement industry. Though more and more Americans are taking supplements — sales have been growing faster than pharmaceuticals in recent years, and the US market tops $30 billion annually— the industry currently receives only light oversight from the FDA.

Unlike pharmaceutical drugs, supplement manufacturers are not required to prove that their products are safe or that they actually do what they are marketed for in humans. They're only required ensure that the supplement bottles contain what's listed on their label — and an estimated 70 percent of supplement manufacturers don't even do that.

Cohen believes we're going to look back at the current free-for-all 50 years from now and think it was insane to let supplements reach consumers with only the faintest whiff of quality control.

Some supplements are as powerful as pharmaceutical-strength drugs

In Cohen's most recent study, published today in the journal Drug Testing and Analysis, he and other researchers at National Center for Natural Products Research in Mississippi looked at 49 botanical dietary supplements that supposedly contained yohimbine, an extract from the evergreen tree yohimbe.

Yohimbine is currently banned in a number of countries after being linked to patient hospitalizations, but it can still be found in many dietary fitness and sex-drive enhancing botanical supplements in the United States. So Cohen and his co-authors were curious to discover how much yohimbine was actually in these supplements.

The results were surprising. Only three of the 49 supplements analyzed contained the amount of yohimbine advertised on the label. In many cases, the supplements were packed with far, far more yohimbine than advertised — the sorts of high doses usually found in pharmaceutical-strength pills. (Doctors can prescribe high-dose capsules of yohimbine, which are regulated like other pharmaceuticals, although this drug has fallen out of favor because of its risky side effects.)

It's unclear how these supplement manufacturers obtained such potent doses of yohimbine. In theory, the pills are only supposed to contain natural ingredients. But if these manufacturers were synthesizing yohimbine in a laboratory, then they are clearly selling mislabeled pharmaceuticals, which is illegal.

"We have no way to know if the potent prescription-strength drug is isolated from the bark of the tree or if it’s made in a factory," Cohen added. "I don’t want to imply that the companies are making synthetic yohimbine and placing it into these supplements — although I would urge the FDA to inspect every factory where yohimbe supplements are being produced to find out exactly how the companies are able to achieve such high levels of yohimbine in the supplements."

This isn't the first time Cohen has come to such a startling conclusion when he examined the contents of popular botanicals. In April, he and his co-researchers found that some popular dietary supplements contain amphetamine-like chemicals stimulants that had never been tested in humans — even though they're marketed as "natural." Last year, the researchers also found many supplements contained another new, designer stimulant called DMBA that had also never been tested in humans.

Others who are investigating the supplement industry have come to similar conclusions about the quality of natural supplements. Early this year, an investigation by the New York attorney general's office found that many supplements being sold at Walgreen, Walmart, GNC, and Target don't actually contain the active ingredients listed on their labels. (So ginseng or St. John's wort supplements didn’t necessarily contain those plants.)

These products can carry serious side effects. According to the New York Times, there were 2,292 serious illnesses and 33 deaths related to supplements between June 2009 and June 2011. Many of these supplements don't work as indicated. An analysis by Consumer Reports found that one-third of the more than 50,000 supplements in the Natural Medicines Comprehensive Database have only "some level of safety and effectiveness that is supported by scientific evidence." Twelve percent have been associated with safety or quality concerns.

How the supplement industry gets away with lax regulation

Dietary supplements are regulated like foods — not like drugs — under the Dietary Supplement Health and Education Act of 1994. Pill-makers can basically put whatever claims they want on their bottles. Specifically, supplement manufacturers can make three types of health claims:

The label of a dietary supplement or food product may contain one of three types of claims: a health claim, nutrient content claim, or structure/function claim. Health claims describe a relationship between a food, food component, or dietary supplement ingredient, and reducing risk of a disease or health-related condition. Nutrient content claims describe the relative amount of a nutrient or dietary substance in a product. A structure/function claim is a statement describing how a product may affect the organs or systems of the body and it can not mention any specific disease.

To remove a supplement from the market, the FDA first has to prove that it's not safe. This is basically the opposite of how pharmaceuticals are regulated, where drug makers need to prove their medicines are safe and effective through high-quality scientific studies before they reach consumers.

There's also another reason for the lax regulation of the supplement industry: Over the past few decades, fierce lobbying efforts by industry groups, coupled with work by a few influential lawmakers, have pushed back bills that would bring supplement regulation closer in line with pharmaceutical regulation.

Journalist Lynn Stuart Parramore detailed the incredible extent of the conflicts of interest here in a piece for Al Jazeera:

Corporate giants in the supplement industry have maintained their free hand by courting select politicians. The Congressional Dietary Supplement Caucus (yes, there is such a thing) boasts power brokers from both parties, such as Sen. Orrin Hatch, R-Utah, and Sen. Tom Harkin, D-Iowa.

Hatch is a hero in Utah County, Utah — a region known as the Silicon Valley of the nutritional supplement industry — for winning a key battle in 1994, when he and Harkin pushed the Dietary Supplement Health and Education Act through Congress. The law allowed supplement manufacturers to test their products on a voluntary basis before selling them and blocked the FDA from regulating them unless there was evidence of harm. Thanks to the senators' efforts, the U.S. population became guinea pigs.

Hatch's industry ties encompass former aides and family members, including his son, a supplement lobbyist in Washington. The pharmaceutical and health-products industry ranks as Hatch's second-biggest financial supporter.

Unsurprisingly, as Parramore points out, the supplement industry has also invested money to counter any regulatory challenges. In some cases, they have help from Big Pharma. Drug companies such as Pfizer, Bayer, and Procter & Gamble own supplement makers.

According to the Economist, while the supplement lobbying budget is $6 million, the FDA’s Division of Dietary Supplements budget — to regulate the industry — has $5.2 million. In other words, the supplement lobbying effort is more flush with cash than the regulator.

The push for reform will have to come from concerned consumers

As academics like Cohen keep amassing evidence on the problems with these pills, other state attorneys general joined New York’s Eric Schneiderman, asking Congress to investigate — and consider clamping down on — the US supplements industry. They want to give the FDA more regulatory power.

So far, bills to reform supplement regulation have flopped. Still, Cohen is hopeful we'll see change in the future.

"The current status quo is not workable for consumers who seek safe natural supplements," he said. As we learn more about the risks of using poor-quality supplements, he believes the push to reform the law will only grow. "Consumers will demand these changes to ensure that what is listed on the label is what found in the pills and powders inside the bottle."

Correction: A previous version of this article misstated the number of yohimbine supplements that contained the amount of the extract advertised on the label.