"Supervitamin Chocolate contains huge amounts of vitamin A and vitamin B. It also contains vitamin C, vitamin D, vitamin E, vitamin F, vitamin G, vitamin I, vitamin J, vitamin K, vitamin L, vitamin M, vitamin N, vitamin O, vitamin P, vitamin Q, vitamin R, vitamin T, vitamin U, vitamin V, vitamin W, vitamin X, vitamin Y, and, believe it or not, vitamin Z! The only two vitamins it doesn't have in it are vitamin S, because it makes you sick, and vitamin H, because it makes you grow horns on the top of your head, like a bull. But it does have a very small amount of the rarest and most magical vitamin of them all — vitamin Wonka!"
— Charlie and the Chocolate Factory

As Willy Wonka's enthusiasm demonstrates, consumers can be bombarded by information about health and nutrition. Although this list comes from a fictional children's story, it does show how easy it is to become confused when deciding which vitamin supplements to take.

It seems like a new study is released on nutrition and vitamins every week. One day, the headlines tell you to load up on a particular supplement, and the next, you're told to stay away from it.

It's enough to make most people throw up their hands in defeat.

Still, consumers are increasingly searching out this type of information. The federal government's Canadian Health Network has said that at least 66 per cent of Canadians with internet access sought out health information on the internet on a regular basis.

"There have been a lot of studies coming out, and I would say it's because of an increasing popularity of natural health products with consumers, so everybody wants to get in on the action and see what they can find out," says Anne Wilkie, vice-president and head of regulatory affairs for the Canadian Health Food Association.

So how do consumers wade through the information effectively?

It's not easy, say the experts.

Learning what's best for you

In the latest confusing example, a study in the Feb. 28 issue of the Journal of the American Medical Association found that using antioxidant supplements such as vitamin A, E and beta-carotene not only didn't add to one's general well-being but may even increase the risk of early death. It also found that there were no improvements to longevity for those taking vitamin C.

These results contradicted other evidence that adding more antioxidants to your diet can combat the free radicals in the body that are thought to cause many diseases, including cancer, heart disease, diabetes and arthritis.

Wilkie says this meta-analysis — a study of 68 earlier studies on the effects of antioxidants — undermines a large body of scientific evidence. "A growing number of evidence-based studies continue to show the health benefits of antioxidants and cannot be discounted," she says.

This one, though, compared studies with different populations (healthy people versus those with serious illnesses) as well as comparing people taking different dosages of the supplements and taking them for different lengths of time. And that may have skewed its findings.

What's more, says Wilkie, "antioxidants aren't promoted to prevent mortality. That's not what the claim on the label is. There's other claims that are made for it. You've got to look at what they're trying to achieve and whether that's even how these products are marketed in the first place."

Vitamin-takers read your labels

In another example, Wilkie talked about a 2001 study, also given prominence in the Journal of the American Medical Association, which found that St. John's wort was not effective in treating severe depression.

The problem with that conclusion, she says, was that the natural health product was never meant to do that — it had been promoted to treat milder forms of depression. Reinhold Vieth, a professor of nutritional science at the University of Toronto, says consumers should also be wary of provocative news headlines on health and nutrition stories, because a lot of times, the story isn't news at all.

In the case of the latest antioxidant articles, he says, "the story originated in the early '90s with epidemiology. [The first reports said] people who eat foods with antioxidants live longer and have less cardiovascular disease with less cancer. Then in the later '90s there were randomized clinical trials where people were given antioxidants and nothing happened. Now they're doing meta-analysis that says nothing happens. To me it's old news because it came out 10 years ago."

He reminded us that a similar story came out in November 2004 warning of the risk to people who took 400 international units of vitamin E daily for longer than one year. The high doses seemed to increase the risk of death, though the effect of smaller doses was unclear.

And yet, Vieth says, good-news stories don't always get as much play. For example, two separate meta-analyses from researchers at the University of California at San Diego in early February of this year found that taking high levels of vitamin D can reduce the risk of breast and colorectal cancer. But he says these types of stories don't cause as much of a stir. Vieth also says to be wary of who is behind the particular media story. "Unfortunately, in terms of the media, when it comes to medical stories, the media take what is ladled out to them by the purveyor of the information. The key journals do press releases and they pick whatever they think is the most exciting or provocative [thing] for their own purposes."

Get help interpreting data

Vieth and Wilkie both say that consumers cannot realistically approach the myriad of studies out there without the guidance of a health professional. "Unfortunately, you have to be a scientist or have a good science background to interpret a lot of this data," Wilkie says. She suggests asking a pharmacist, reputable health food store, naturopath or doctor for help in deciding which supplements to take.

Jason Bouzanis, a media relations officer with Health Canada, says that the agency recommends people inform their doctor about the medications and any natural health products they are using, including herbal products and vitamins.

Health Canada also recommends that if consumers decide they want to take supplements, they should make sure the products have labels containing either a Drug Identification Number (DIN) or a Natural Product Number (NPN). The agency is currently undergoing a process of issuing licenses for all natural health products. "These numbers indicate that Health Canada has reviewed the product for safety, efficacy and quality," says Bouzanis.

The experts agree that despite the numerous studies on vitamins released each month, there really is no replacement for eating healthy foods.

Vieth says that in his opinion, the newly updated Canada's Food Guide recommendations are among the best advice for consumers looking for nutritional information. The guide doesn't recommend people take any supplements except a multivitamin containing folic acid for pregnant women and vitamin D to protect bones for men and women over 50.

"The science," Vieth says, "is that people who eat food like tomatoes, carrots — vegetables — tend to live longer. You can't just crush all the stuff from the vegetables into something called vitamin A or vitamin E."

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