Vitamin D may be a hot seller during the long winter months in Canada, but a new study has found evidence that the supplement is lacking any substantial health benefits.

Older studies have shown people who are vitamin D deficient are more likely to be ill and have a variety of diseases, but the new analysis of 40 clinical trials, published this week in The Lancet, suggests taking the supplement to boost levels won’t reduce rates of heart disease, strokes, cancer or fractures.

“A lot of people spend a lot of money on vitamin D supplements and many of them are not going to be getting benefits from it,” said study co-author Dr. Mark Bolland of the University of Auckland.

What’s more, the scientists say the data from more than 37,000 people was so conclusive that future studies are likely futile.

But researcher Reinhold Vieth, of the University of Toronto, says the research is based on outdated information. He said there is plenty of evidence that higher vitamin D levels are linked to good health.

“Older studies that are using doses that are actually at or below the recommended dietary allowance that’s current,” he told CTV News.

Vieth said studies looking at vitamin D as a preventative treatment for heart disease and cancer are now underway using much higher doses -- 2,000 or 3,000 international units per day -- to see if they will prevent diseases.

“We have to wait until roughly the year 2017 before the larger studies that are ongoing, will come out,” Vieth said.

Other research suggests it may be the actual sunlight, not pills, that make people healthier, and that sunlight exposure may be beneficial for cardiovascular health.

Dermatologist Dr. Richard Weller said more research into the benefits of sunlight and vitamin D is needed.

“I think this is an unfolding story. As we get more data, we adapt our messages as we understand better,” he said. “And I think this is an example of that.”

As for the supplements, the researchers said there was no evidence that they cause harm.

With a report from CTV Medical Specialist Avis Favaro and producer Elizabeth St. Philip