"My understanding is that Canada has some of the best good manufacturing practice standards in the world," said Heather Boon, interim dean of pharmacy at the University of Toronto. "I've been telling consumers for years to buy Canadian because you're more likely to get a higher-quality product because of our regulations."
But Boon, who also co-directs the Canadian Interdisciplinary Network for Complementary and Alternative Medicine Research, said the results of the study do raise some questions about whether more needs to be done.
In 2004, new manufacturing rules were put in place for natural health products.
"This particular study seems to suggest that may not be enough to make sure the right product is ending up in the right bottle," Boon said.
'Serious health risks'
In the recent study, researchers at the University of Guelph used DNA barcode testing to probe 44 herbal products from 12 companies. They discovered there was product substitution in 20 of the 44 products tested and only two companies had products without any substitution, contamination or fillers. Scientists also said that some of the contaminants found posed "serious health risks to consumers."
"It is a real problem and it will continue to be a problem," said David Bailey, a clinical pharmacologist at the Lawson Health Research Institute based in London, Ont.
"These [products] are easy to get. They require no supervision from a health-care professional of any kind. You can walk into a Loblaws or Shoppers Drug Mart … pick these things up and walk out without ever having discussed any of the issues that may be relevant."
Natural health products are defined as some compound that exists in nature that is used for health purposes. The 2004 regulations sought torequire companies to provide evidence of their safety and efficacy and follow good manufacturing processes by disclosing information about what's in the product, how it's made, how it's stored and distributed. Once a product was approved by Health Canada, it would obtain a natural product number (NPN).
"Canada is relatively advanced with its NPN Health Canada structure of needing to submit dossiers for basically every product," said Peter Jones, director of the University of Manitoba's Richardson Centre for Functional Foods and Nutraceuticals. "Whereas in the U.S and many other jurisdictions ... it's more of a wild west cowboy land where you put whatever you want into a product and you basically get it out there."
But there continues to be a huge backlog of products still on the market that have yet to be approved by Health Canada.
And Health Canada still has not begun the process of policing establishments selling natural heath food products to ensure good manufacturing practices are being followed — a process expected to start next year.
'A lot of hand waving'
"The bark is worse than the bite though," Jones said. "It's a lot of hand waving that we're seeing. It may well be that it will be a softer roll-out simply because of resources. There are only so many Health Canada employees and so many companies that do this sort of thing."
But Jones said he still believes the regulations in place are sufficient.
However, Dr. Matthew Stanbrook, deputy editor of the Canadian Medical Association Journal, said the problems run deeper.
Stanbrook said Health Canada employs a "double standard" by calling for strict controls on drug companies, while being "lax and loose" with natural health products.
He said herbal products don't go through the same rigorous tests for efficacy and safety as pharmaceutical drugs.
Bailey echoed Stanbrook, saying that for standard pharmaceuticals, every element in the formulation of the drug is accounted for, including the specific amount of the active ingredient, how much filler is used and what else has been added.
But the same can't be said for herbal remedies, Bailey noted.
"There are approximately thousands and thousands of different chemicals in there that are not accounted for because it comes from a biological source, and none of that stuff can be truly accounted for. And in most cases nobody knows what the active ingredient is."
Bailey said many of these herbal remedies should be sold behind a counter, where a pharmacist can advise patients about the potential effects of mixing them with medication.
"It should be something where a health-care professional can intervene. And I'm not talking about somebody in a herbal drugstore. I'm talking about someone who has gone through years of training."