Doctors urge public to stop 'wasting money' on vitamin supplements

Canada AM: Vitamins a waste of money? Dr. Marla Shapiro says there is nothing really new about the data, and discusses whether some vitamins may, in fact, be harmful to health.

Five doctors have penned a newly-published editorial that urges the public stop “wasting money” on vitamin and mineral supplements, following the release of two new studies that show that supplements do not prevent chronic diseases or cancer.

Both the editorial and the studies were published in the Annals of Internal Medicine on Monday.

"The message is simple: Most supplements do not prevent chronic disease or death, their use is not justified and they should be avoided," the authors write in the editorial Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements.

The authors reference one study that involved more than 450,000 participants which showed there was no clear evidence of a beneficial effect of supplements on mortality, cardiovascular disease or cancer.

In a new study published Monday, researchers looked at the effects of a daily multivitamin on preventing cognitive decline among nearly 6,000 men aged 65 and older. A follow-up with the participants conducted 12 years later showed there was no difference in overall cognitive performance or verbal memory between the multivitamin group and the placebo group.

A third study also published Monday looks at the potential benefits of high-dose multivitamin on about 1,700 men and women who had suffered a heart attack and were at a high risk of suffering another heart attack or a stroke. A follow-up with the patients more than four years later showed no significant difference in cardiovascular events between the multivitamin group and the placebo group.

"Despite sobering evidence of no benefit or possible harm, use of multivitamin supplements increased among U.S. adults," the authors write.

In the United States the use of multivitamins increased 30 per cent between 1988 and 1994 and 39 per cent between 2003 and 2006, the authors note. Use of dietary supplements increased from 42 per cent to 53 per cent over the same time period.

"Sales of multivitamins and other supplements have not been affected by major studies with null results, and the U.S. supplement industry continues to grow, reaching $28 billion in annual sales in 2010," the authors write.

The editorial also points to clinical trials that have shown beta-carotene, vitamin E and high doses of vitamin A supplements are harmful and can increase mortality.

"We believe that the case is closed," the authors write. "Supplementing the diet of well-nourished adults with (most) mineral or vitamin supplements has no clear benefit and might even be harmful. These vitamins should not be used for chronic disease prevention. Enough is enough."

However, the chief science officer at Jamieson Vitamins, says there are a number of studies that support the use of a vitamin and mineral supplements.

"The way we look at supplements and vitamins and minerals is that being healthy means beyond just not being sick. It means optimizing your physical and mental well-being, and there are plenty of studies out there that support that supplements will have a positive effect," Gary Leong told CTV News.

He pointed out that the authors who penned the editorial looked at isolated studies from which they based their conclusion.

Leong said he encourages consumers to do their own research before deciding whether or not to take multivitamins and supplements.

"The accessibility to information is out there," he said.

Specific cases

One medical expert says while the studies confirm that taking vitamins don’t contribute to reducing disease in the general population, there may be instances where they may be beneficial.

These include people with “certain nutritional or vitamin deficiencies” or with certain medical conditions which require supplementation, said Dr. Young-In Kim, gastroenterologist at St. Michael’s Hospital and an associate professor of medicine and nutritional sciences at the University of Toronto.

“If you have a specific indication to take vitamins, that's fine, you should be taking what's recommended for that specific condition,” he told CTV News. “But for the general population, unless you have a good or reasonable indication, you should not be taking high levels of vitamins or mineral supplementation.”

Sales

Meanwhile, Gary Leong noted that vitamin sales in Canada have been steadily increasing, which he attributes to an aging population with more health information readily available.

"The focus should be on being healthy and our definition of healthy goes beyond just not being sick," he said. "It also encompasses optimizing your physical and mental wellbeing and vitamins really have a role to play in that."

With a report from CTV's medical specialist Avis Favaro and producer Elizabeth St. Philip