Contaminants Found in 90% of Herbal Supplements Tested


The majority of dietary supplement facilities tested were found noncompliant with good manufacturing practices guidelines.

“The U.S. public is not well protected” by current dietary supplement recommendations, an issue I explore in my video Dangers of Dietary Supplement Deregulation. Sometimes, there is too little of whatever’s supposed to be in the bottle, and other times, there’s too much, as I discussed in my video Black Raspberry Supplements Put to the Test. In one case, as you can see at 0:20 in my video, hundreds of people suffered from acute selenium toxicity, thanks to an “employee error at one of the ingredient suppliers.” Months later, many continued to suffer. Had the company been following good manufacturing practices, such as testing their ingredients, this may not have happened. In 2007, the FDA urged companies to adhere to such guidelines, but seven years later, the majority of dietary supplement facilities remained noncompliant with current good manufacturing practices guidelines.

What are the consequences of this ineffective regulation of dietary supplements? Fifty-thousand Americans are harmed every year. Of course, prescription drugs don’t just harm; they actually kill 100,000 Americans every year—and that’s just in hospitals. Drugs prescribed by doctors outside of hospital settings may kill another 200,000 people every year, but that doesn’t make it any less tragic for the thousands sickened by supplements.

Sometimes the supplements may contain drugs. Not only does a substantial proportion of dietary supplements have quality problems, the “FDA has identified hundreds of dietary supplements…that have been adulterated with prescription medications” or, even worse, designer drugs that haven’t been tested—like tweaked Viagra compounds. About half of the most serious drug recalls in the U.S. aren’t for drugs but for supplements, yet two-thirds or recalled supplements were still found on store shelves six months later.

There is also inadvertent contamination with potentially hazardous contaminants, such as heavy metals and pesticides in 90 percent of herbal supplements tested, as you can see at 2:09 in my video. Mycotoxins, potentially carcinogenic fungal toxins like aflatoxin, were found in 96 percent of herbal supplements. Milk thistle supplements were the worst, with most having more than a dozen different mycotoxins. It’s thought that since the plant is harvested specifically when it’s wet, it can get moldy easily. Many people take milk thistle to support their livers yet may end up getting exposed to immunotoxic, genotoxic, and hepatotoxic—meaning liver toxic—contaminants. How is this even legal? In fact, it wasn’t legal until 1994 with the passage of the Dietary Supplement Health and Education Act. Prior to that, supplements were regulated like food additives so you had to show they were safe before they were brought to market—but not anymore. Most people are unaware that supplements no longer have to be approved by the government or that supplement ads don’t have to be vetted. “This misunderstanding may provide some patients with a false sense of security regarding the safety and efficacy of these products.”

This deregulation led to an explosion in dietary supplements from around 4,000 when the law went into effect to more than 90,000 different supplements now on the market, each of which is all presumed innocent until proven guilty, presumed safe until a supplement hurts enough people. “In other words, consumers must suffer harm…before the FDA begins the slow process toward restricting [a] product from the market.” Take ephedra, for example. Hundreds of poison control center complaints started back in 1999, increasing to thousands and including reports of strokes, seizures, and deaths. Yet the FDA didn’t pull it off store shelves for seven years, thanks to millions of dollars from the industry spent on lobbying.

What did the companies have to say for themselves? Metabolife swore that it had never received a single report of a single adverse effect from any customer. “According to the company, Metabolife had a ‘claims-free history’” when in fact it had gotten 14,000 complaints from customers, but covered them up. Basically, “dietary supplement manufacturers have no realistic accountability for the safety of their products,” and the industry trade organizations have been accused of responding to legitimate concerns with “bluster and denial.” Yes, but are these criticisms of dietary supplements just a Big Pharma conspiracy to maintain its monopoly? No. Big Pharma loves dietary supplements because Big Pharma owns dietary supplement companies to dip into the tens of billions in annual sales.

Isn’t the supplement issue insane? For more, check out:

More than a hundred thousand people are killed every year by pharmaceuticals? Learn more:


Does Aspartame Cause Lymphoma?

The approval of aspartame has a controversial history. The Commissioner of the U.S. Food and Drug Administration (FDA) concluded that “there is a reasonable certainty that human consumption of aspartame: (1) …will not pose a risk of brain damage resulting in mental retardation, endocrine [hormonal] dysfunction, or both; and (2) will not cause brain tumors.” However, the FDA’s own Public Board of Inquiry withdrew their approval over cancer concerns. “Further, several FDA scientists advised against the approval of aspartame, citing…[the aspartame company’s] own brain tumor tests…” Regardless, the Commissioner approved aspartame before he left the FDA and went on to enjoy a thousand-dollar-a-day consultancy position with the aspartame company’s PR firm. Then, the FDA actually prevented the National Toxicology Program (NTP) from doing further cancer testing. As I discuss in my video Does Aspartame Cause Cancer? we were then left with people battling over different rodent studies, some of which showed increased cancer risk, while others didn’t.

This reminds me of the saccharin story. That artificial sweetener caused bladder cancer in rats but not mice, leaving us “to determine whether humans are like the rat or like the mouse.” Clearly, we had to put the aspartame question to the test in people, but the longest human safety study lasted only 18 weeks. We needed better human data.

Since the largest rat study highlighted lymphomas and leukemias, the NIH-AARP study tracked blood cancer diagnoses and found that “[h]igher levels of aspartame intake were not associated with the risk of…cancer.” Although the NIH-AARP study was massive, it was criticized for only evaluating relatively short-term exposure. Indeed, people were only studied for five years, which is certainly better than 18 weeks, but how about 18 years?

All eyes turned to Harvard, where researchers had started following the health and diets of medical professionals before aspartame had even entered the market. “In the most comprehensive long-term [population] study…to evaluate the association between aspartame intake and cancer risk in humans,” they found a “positive association between diet soda and total aspartame intake and risks of [non-Hodgkin’s lymphoma] and multiple myeloma in men and leukemia in both men and women,” as you can see at 2:12 in my video. Why more cancer in men than women? A similar result was found for pancreatic cancer and diet soda, but not soda in general. In fact, the only sugar tied to pancreatic cancer risk was the milk sugar, lactose. The male/female discrepancy could have simply been a statistical fluke, but the researchers decided to dig a little deeper.

Aspartame is broken down into methanol, which is turned into formaldehyde, “a documented human carcinogen,” by the enzyme alcohol dehydrogenase.The same enzyme that detoxifies regular alcohol is the very same enzyme that converts methanol to formaldehyde. Is it possible men just have higher levels of this enzyme than women? Yes, which is why women get higher blood alcohol levels than men drinking the same amount of alcohol. If you look at liver samples from men and women, you can see significantly greater enzyme activity in the men, so perhaps the higher conversion rates from aspartame to formaldehyde explain the increased cancer risk in men? How do we test this?

Ethanol—regular alcohol—competes with methanol for this same enzyme’s attention. In fact, regular alcohol is actually “used as an antidote for methanol poisoning.” So, if this formaldehyde theory is correct, men who don’t drink alcohol or drink very little may have higher formaldehyde conversion rates from aspartame. And, indeed, consistent with this line of reasoning, the men who drank the least amounts of alcohol appeared to have the greatest cancer risk from aspartame.

A third cohort study has since been published and found no increased lymphoma risk associated with diet soda during a ten-year follow-up period. So, no risk was detected in the 18-week study, the 5-year study, or the 10-year study—only in the 18-year study. What should we make of all this?

Some have called for a re-evaluation of the safety of aspartame. The horse is kind of out of the barn at this point with 34 million pounds of aspartame produced annually, but that doesn’t mean we have to eat it, especially, perhaps, pregnant women and children.

For more information on the effects of aspartame, watch my videos Aspartame and the Brain and Aspartame-Induced Fibromyalgia. Interested in learning more about the effects of consuming diet soda? See, for example:

What about Splenda? Or monk fruit sweetener? I have videos on those, too—watch Effect of Sucralose (Splenda) on the Microbiome and Is Monk Fruit Sweetener Safe?.

I also do a comparison of the most popular sweeteners on the market, including stevia and xylitol, in my video A Harmless Artificial Sweetener.

Perhaps the best candidate is erythritol, which you can learn about in my video Erythritol May Be a Sweet Antioxidant. That said, it’s probably better if we get away from all intense sweeteners, artificial or not. See my video Unsweetening the Diet for more on this.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Do Poultry Viruses Cause Human Cancers?

The incidence of cancers has been rising for the last half century, and the question is why? Up to 20 percent of all cancers are caused by infectious agents, chiefly viruses. We’ve known this was possible for a century, when a cancer-causing virus was discovered in chickens. The idea was considered such heresy that Dr. Peyton Rous, the man who made this landmark discovery, wouldn’t get his Nobel Prize until 55 years later.

If there are cancer-causing chicken viruses, might they have any effect on people who handle or eat poultry? Concern has been raised about the potential infectivity of cancer-causing farm animal viruses for decades. The first question was whether there was any evidence of human exposure, and, indeed, people do have antibodies to these cancer-causing chicken viruses in their bloodstream. This indicates that the virus is no stranger to our immune systems. Is there any evidence, though, that the virus itself can get into our blood? There wasn’t any such evidence…until 2001.

As I explain in my video The Role of Poultry Viruses in Human Cancers, there is a cancer-causing herpesvirus in poultry, but does it pose a public health hazard? Researchers used DNA fingerprinting techniques to test the blood of 202 people and found that 20 percent, or one in five individuals, had viral DNA in their bloodstream. Testing positive for avian herpesvirus doesn’t mean these diseases can necessarily infect human cells, however. But, as it turns out, they can indeed.

But do they cause human disease? How can that be figured out? Since we can’t just inject people, researchers looked at poultry workers, which is the way we figured out how other farm animal diseases, such as brucellosis and anthrax, jumped to humans. In fact, studying workers is also how we discovered the carcinogenic nature of things like asbestos and benzene. If the poultry workers, who are exposed day in and day out, don’t have higher cancer rates, then presumably the viruses are harmless. Unfortunately, they do have higher rates. In fact, those with high exposure to cancer-causing poultry viruses have “increased risk of dying from several cancers.”

As such, “the relative ease” with which some of the viruses can infect human cells, as well as infect and cause tumors in primates in laboratories, “may be of public health significance, particularly because of the…increased risk of cancer in meat workers” and the evidence that we may become infected with these viruses. However, even if poultry workers are at risk, it doesn’t mean people who merely eat chicken or eggs are. For example, workers who kill chickens were found to be six times more likely to die from brain cancer compared to workers who do not kill poultry, but the slaughterers have live birds flapping in their faces. The “intensity of exposure to these viruses in the general population cannot be expected to be as high as those experienced by poultry workers…[but] the general population is nevertheless widely exposed” to the viruses simply because we eat so many chickens and eggs.

This is supported by data showing that it’s not only the factory farm workers who are at higher risk for brain tumors, but also butchers and meat cutters who have no exposure to live birds, particularly those who don’t wear gloves and frequently have cuts on their hands. These workers are at higher risk for other cancers, as well.

Those who handle meat for a living also have higher rates of non-cancer mortality, such as increased death from heart disease and other health concerns outlined at 3:32 in my video. Some of the poultry viruses not only cause cancer in chickens, but also atherosclerosis. Indeed, that cancer-causing poultry herpesvirus also triggers the buildup of cholesterol crystals in chickens. But, what about in people? “Because chickens infected with Marek disease virus, a herpesvirus, develop atherosclerotic lesions after infection, [researchers] looked for the presence of herpesvirus or parts thereof in human artery wall tissue…” Evidence of the virus was found, though any role they play in human heart disease remains speculative.

“Considerable attention has been paid to substances present in animal food before and after cooking as risk factors for human diseases such as heart disease, diabetes, and various cancers…[and] exposures have included heme [iron], fat or cholesterol, dioxins,” and the cooked meat carcinogens. We didn’t think, however, about the animal viruses, which “are important not only for supermarket workers and other workers in the meat and poultry industries, but also because the general population is exposed.” Indeed, the study that found chicken virus DNA circulating in people’s bloodstreams also found about the same rates in office workers as they did in chicken slaughterhouse workers, which you can see at 4:42 in my video.

Other viruses may actually play a role in the obesity epidemic. See, for example, Infectobesity: Adenovirus 36 and Childhood Obesity

For other potential microbiological hazards in poultry, check out:

And, for potential chemical hazards in poultry, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: