Millions may be wasting their time and money because a major study has found that the most popular vitamin and mineral supplements do not make people healthier.
Most household vitamin and mineral supplements do not provide any health benefits whatsoever - and some could even increase the risk of death, scientists claim.
The most popular vitamin and mineral supplements were found to not give any health benefits - including vitamin C pills and calcium tablets.
Instead, scientists advise people get all their nutrients from a healthy diet.
A study reviewed the most common supplements taken by the general population including A, B1, B2, B3 (niacin), B6, B9 (folic acid), C, D and E.
They also included the minerals Î²-carotene, calcium, iron, zinc, magnesium, and selenium.
Multivitamins, vitamin D, calcium and vitamin C showed no advantage or added risk in the prevention of cardiovascular disease, heart attacks, strokes or premature death.
Danger of death
But niacin and antioxidants showed signs they could actually be harmful - because they showed a very small increased risk of death from any cause.
It was not all bad news, however, because folic acid was the only supplement that could be proven to reduce the risk of heart disease or a stroke.
Experts concluded you are better off eating less processed plant foods including vegetables, fruits and nuts instead of taking multivitamins.
Dr David Jenkins, the study's lead author, said: "We were surprised to find so few positive effects of the most common supplements that people consume.
"Our review found that if you want to use multivitamins, vitamin D, calcium or vitamin C, it does no harm - but there is no apparent advantage either.'
"These findings suggest that people should be conscious of the supplements they're taking and ensure they're applicable to the specific vitamin or mineral deficiencies they have been advised of 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.
"So far, no research on supplements has shown us anything better than healthy servings of less processed plant foods including vegetables, fruits and nuts."
The study was published in the Journal of the American College of Cardiology using existing data and single randomised control trials from January 2012 to October 2017.
Dr Jenkins is Director of the Clinical Nutrition and Risk Factor Modification Centre, scientist at the Li Ka Shing Knowledge Institute of St. Michael's Hospital and university professor in the Department of Nutrition Sciences and Medicine at the University of Toronto.
This study was funded by the Canada Research Chair Endorsement, Loblaw Cos. Ltd., and the Canadian Institutes for Health Research.