Almost 40 per cent of adults say they have taken vitamin and mineral supplements, Statistics Canada reports, but the practice may be worth rethinking, nutrition and medical experts say.

Decades ago, nutritional deficiencies were common among the general population in Canada. Since then, staple foods such as milk, flour and table salt have been fortified with vitamins and minerals to address those deficiencies.

Julie Meathrell

Julie Meathrell decided to give up on taking vitamin supplements, which were costing $70 to $80 a month, and now relies on fruits and vegetables. (CBC)

In the last three years, study after peer-reviewed study have shown next to no measurable health benefits from common store-bought vitamins or multivitamins for otherwise healthy people.

Most family physicians won't discourage taking vitamins because there are few risks. 

But why were vitamins so popular  in Statistics Canada's 2009 report?

"There's a certain amount of guilt about not eating well, and that's an easy fix," said nutrition Prof. Mary L'Abbé at the University of Toronto. "'Hmm, I've skipped meals, we didn't have breakfast, we didn't do lunch,' and that's often what people are doing, using it as an insurance policy. But it's only half-coverage."  

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Small segments of the Canadian population show inadequate vitamin intake, but it's often because people are making poor nutritional choices, such as drinking lots of sweetened beverages that don't offer many nutrients, L'Abbé said.

"If you look at the scientific evidence in terms of nutrition and health outcomes, the biggest problems aren't from vitamin or mineral deficiency. They're from too many calories, too much sodium, high trans fat, high sugar intake, not enough fruits and vegetables. The things that characterize healthy diets, that's the biggest predictors of … being healthy later on in life."

There are some cases when doctors will recommend supplements, such as vitamin D for breastfed infants, adults who don't get enough sun or in some patients after surgery.

When family physician Dr. Nav Persaud of St. Michael's Hospital in Toronto talks to patients about all the pills they're taking, he often discusses the pros and cons of taking vitamins.

"For example, folic acid is a vitamin that's in many multivitamins," Persaud said. "Folic acid does help prevent certain birth defects. But when older people take folic acid, it may well increase the risk of cancer without providing any benefit."

Julie Meathrell of London, Ont., used to take vitamin supplements based on the advice of friends and from reading books and online sources — until the costs added up.

"I would say probably anywhere from $70 to $80 a month," she recalled.

Meathrell decided to ditch her supplements and now gets her vitamins from fruits and vegetables.