Earlier this month, CBC Marketplace yet again launched an assault on natural health products, this time taking aim at green tea. Yes, tea which is consumed by people worldwide in quantities second only to water found itself in the cross-hairs of the highly alarmist and sensationalizing reporting of CBC Marketplace.

Much like last time the CBC Marketplace ran an assault against the natural health industry, I felt compelled to fact check some of their highly inaccurate claims. Shortly thereafter, CBC Marketplace actually quietly published a statement retracting some of their findings because they made a mistake. Oops!


Let’s look at some of the larger points made by CBC Marketplace and our response.

CBC Statement : Marketplace discovered more than 60 documented cases worldwide of liver failure associated with green tea supplements reported in peer-reviewed journals.

Our Response : CBC Marketplace reported that 60 cases of liver failure occurred as the result of green tea supplement consumption. A review of the literature actually suggested that there was only 1 actual case of liver failure requiring a liver transplant, whereas the remainder of cases were actually diagnosed with hepatotoxicity; quite a tremendous distinction. Some cases of hepatotoxicity “associated” with green tea beverage consumption have also been sited in the literature, but were conveniently left out of the Marketplace report to ensure that an unbiased report wasn’t made.

Hepatoxicity is a relatively common temporary liver condition caused by substances such as prescription drugs, of which nearly 900 are known to cause many cases of hepatotoxicity. Tylenol alone is responsible for nearly 56,000 emergency room visits, 2,600 hospitalizations and 458 deaths in the United States alone every year. So here we have 60 associated green tea cases worldwide, 1 transplant and (according to the CBC) at least 2 deaths “partially linked” to green out of 7 billion people, vs 458 deaths in the United States per year alone known to have been directly caused by Tylenol usage. What exactly motivated CBC Marketplace to target green tea to vilify when so many easier targets are in sight?

But did green tea supplements actually cause hepatotoxicity? They specifically use the word “associated” which is synonymous with “correlated”. The very definition of this term in statistics cannot be used to imply causation. If I develop pneumonia or pancreatitis while eating a bowl of ice cream, that doesn’t mean that ice cream caused either of those diseases. They may be correlated (in the sense that they occurred together), but ruling out coincidence would be nearly impossible unless there was good reason (aka evidence) to suggest that one may have caused the other – much like we know that excessive drinking causes a hangover, and we know in great detail as to why that is because a causal link and mechanism of action has been established. To this date, there is no known causal link between green tea and developing hepatotoxicity and possible theories as to “why” revolve around questions with respect to the extraction processes, possible contaminants, or merely coincidence.

CBC Marketplace also single-out green tea supplements in their “reporting”, however they failed to mention that several cases of hepatotoxicity have been associated with green tea beverages as well. Again, key word here is "associated".

CBC Statement : People should not assume that because they are marketed as natural products that they are safe.

Our Response :True

The market for weight management and well-being products in Canada is estimated to be worth about $304 million US a year, according to market research firm Euromonitor (though personally I think that market is substantially bigger). Of course, a market that big is bound to lie to increase sales, similar to how CBC Marketplace sensationalizes and distorts data in order to increase viewership with alarmist stories.

Many natural health products can still pose danger, though in reality, it’s a far cry from the harm brought about by cars, air pollution, prescription drugs and even our food. Since 2006, we’ve had federal regulations for natural health products and while not perfect, the NNHPD branch of Health Canada is one of the best in the world. Every label claim, warning, and contraindication required by Health Canada has to be listed on the bottle if it’s to be registered for sale in Canadian retail stores.

CBC Statement: Joyce Boudreau-Hearn, from Mulgrave, N.S., died of complications from liver failure in 2010 after multiple transplants led to infection.

Her daughter, Jocelyn Stewart, says the 55-year-old had been healthy before she started taking a green tea extract sold as a weight-loss supplement. Joyce Boudreau-Hearn died of complications from liver failure at age 55 after multiple transplants led to infection. Her daughter says the Nova Scotia woman was healthy before she started taking a green tea extract sold as a weight-loss supplement.

Our Response : Simply because 2 events occur simultaneously, it doesn’t necessarily imply causation. If I drink a green tea and then eat improperly cooked chicken and get diarrhea, do I blame the green tea or the chicken? Statistics show that the highest percentage of burglaries occur in the summer months; a pattern that is shockingly similar to that of ice cream consumption. Does that mean that ice cream causes a person to want to commit burglary? Or that burglars like to eat ice cream after a job? Or that it’s merely hot outside and both burglars and ice cream sales benefit from the heat. And when did her daughter become a coroner who is able to determine that the green tea killed her? These are all questions worth considering, even if CBC Marketplace found it more lucrative to viewership by encouraging their audience to connect these dots and become enraged and shocked by the (faulty) conclusions.

CBC Statement: Bonkovsky, along with other experts, isn't exactly certain why the extracts can affect some people's livers and not others. But generally he says high doses can pose a danger to the liver.

"If you take enough of it, it can kill you," Bonkovsky says.

Our Response : New data from the Canadian Centre of Obvious Statements has also reported that other substances such as prescription drugs, alcohol, cigarettes and even water can kill you if you consume enough of them. Currently, all substances currently sold in Canada are under review for being hazardous to human health if consumed in quantities equal or greater to that of body weight.

CBC Statement: Marketplace looked at the research Health Canada used to determine that green tea extract products are effective treatments for weight management.

To evaluate the studies, Marketplace turned to McMaster University epidemiologist Jason Busse, who found the research couldn't determine whether green tea actually contributed to weight loss.

"All the studies have important limitations that preclude any confident conclusion that green tea preparations reduce weight," Busse says.

Our Response: We would agree. The number of natural health products that have any credible evidence to suggest that they may help with weight loss is probably less than about 5. I personally would put green tea extracts on this list. Despite this, the actual degree of effect of green tea on weight management is still relatively small and inconsistent. The quality and concentration of catechins and EGCG varies greatly from product to product as well.

This is the second critical review our website has published with respect to CBC Marketplace stories. As much as I love tearing apart the nutritional science facts that CBC Marketplace tends to misreport, I hope it’s the last.