If you are taking vitamins and minerals in the hope of preventing a heart attack or stroke, you might as well put your cash through a paper shredder. The most popular supplements provide no real health benefits, a new study finds.

The study reviewed five years of published research on supplements that included vitamins A, C, D, E and five B vitamins (B1, B2, niacin, B6, folic acid); the minerals, calcium, iron, zinc, magnesium and selenium; and beta-carotene.

“So far, no research on supplements has shown us anything better than healthy servings of less processed plant foods including vegetables, fruits and nuts.”

Multivitamins, vitamins C and D, and calcium were of no benefit when it came to preventing cardiovascular disease, heart attack, stroke or premature death, researchers from the University of Toronto and St. Michael’s Hospital found.

Folic acid taken by itself and B-vitamins with added folic acid might lower the risk of developing cardiovascular disease or having a stroke, according to the study's results. Niacin, a B vitamin, and antioxidants had a small effect that could result in an increased risk of death from any cause.

David Jenkins of St. Michael’s Hospital and lead author of the study advised people to be aware of what they are choosing and take only supplements for vitamin or mineral deficiencies as prescribed by their healthcare provider.

“In the absence of significant positive data — apart from folic acid's potential reduction in the risk of stroke and heart disease — it's most beneficial to rely on a healthy diet to get your fill of vitamins and minerals,” said Jenkins, in a statement. “So far, no research on supplements has shown us anything better than healthy servings of less processed plant foods including vegetables, fruits and nuts.”

In other words, a bad diet with supplements is still a lousy diet. Spend your money on fresh, unprocessed foods to get the best nutrition, not on supplements that have no proven benefit and may even cause harm.

The study is published in the Journal of the American College of Cardiology.