Companies that sell natural health products will soon have unprecedented freedom to promote the ability of vitamins, herbal supplements and non-prescription drugs to prevent serious diseases and medical conditions, including cancer, heart disease and arthritis.
The changes to the federal rules, which take effect June 1, represent a significant boost for the natural health industry, which is eager to increase its credibility and capitalize on a booming market for vitamins and botanical supplements by directly marketing their health claims to consumers.
But medical experts and consumer advocates warn the federal government's decision could result in a flood of deceptive claims about natural health products that are backed up by inadequate or even flawed scientific evidence.
"It seems to me they're [Health Canada] authorizing wholesale misleading claims," said Bill Jeffery, national co-ordinator for the Centre for Science in the Public Interest. "They're giving industry even more latitude and they're prepared to approve even more impressive claims about more worrisome diseases with very little evidence."
Natural health products are regulated by Health Canada and include vitamins, minerals, herbal supplements and homeopathic medicines such as echinacea, St. John's wort and vitamin D.
Companies have traditionally been allowed to make limited claims about the ability of some products to promote good health or prevent some mild conditions, such as the common cold.
But until now, they have been strictly prohibited from making any claims about serious diseases, including asthma, cancer and diabetes. The restrictions were designed to prevent companies from making false or misleading claims directed at people with serious diseases or medical conditions, according to Health Canada.
The new rules are set to change all that to reflect a growing demand for information about the possible benefits of herbal remedies. Consumers want to know, for instance, that vitamin D may reduce the risk of cancer or that aspirin can help prevent heart disease, said Supriya Sharma, director-general of Health Canada's therapeutics products directorate.
Companies in the industry say the changes will help Canadians choose products that have the potential to help them.
"Consumers want to understand the products that they're purchasing and what the benefits of those products are," said Penelope Marrett, president of the Canadian Health Food Association.
But Lloyd Oppel, physician at the University of British Columbia Hospital who evaluates evidence behind medical claims, says the regulations are only about making manufacturers happy.
"They have nothing to do with protecting Canadians," he said. "If you tell people that they can do certain things with medications, it's going to at least misinform them, maybe spend their money poorly and may delay getting proper care."
One of the major problems Dr. Oppel and other medical experts cite with allowing companies to say their products prevent serious diseases is that scientific proof is scant or inadequate.
Health Canada said companies will have to provide varying levels of evidence from clinical trials before they're allowed to make prevention claims on their products for serious diseases.
"It depends on the nature of the claim and what we already know about the product. The more serious the claim, the higher the level of evidence that would be expected," said Robin Marles, director of the bureau of clinical trials and health sciences at Health Canada's natural health products directorate.
"There are those who will always be skeptical and perhaps that's not such a bad thing because in the end that ensures that our industry has the best evidence possible for the products it makes and supplies to Canadians," Ms. Marrett said.
But most studies on natural health products are funded by companies that have a vested interest in finding a positive result, which means the benefits of many products can be overstated, said David Bailey, a pharmacology professor at the University of Western Ontario who studies interactions between food, drugs and natural health products.
