A new study demonstrates the ineffectiveness of dietary supplements in reducing the risk of death. Some may even have the opposite effect.

Published in The Annals of Internal Medicine, this research was carried out on 30,899 adult Americans aged 20 and over, who participated in a national survey on health and nutrition between 1999 and 2010.

These participants answered questions on their consumption of dietary supplements.

The purpose of this research, from Friedman School of Nutrition Science and Policy at Tufts University in the United States, was to evaluate the link between use of dietary supplements, the level of nutrients obtained from food and supplements, and mortality in American adults.

Over the course of the study, which lasted for a period of six years, 3,613 people in the study died – 945 from cardiovascular illness and 805 from cancer.

The scientists behind the work discovered that adequate intake of vitamin A, vitamin K, magnesium, zinc and copper were associated with a lower risk of premature death – but only when these nutrients came from food.

The study also demonstrated that people who consume high doses of calcium (1,000mg per day or more) in the form of dietary supplements presented a 53% increased risk of death from cancer.

However, the authors indicated that the link between excess calcium intake and cancer is not yet completely clear and needs further research.

Patients who did not suffer from vitamin D deficiency, but who consumed this nutrient as a supplement in amounts of 10mcg or more per day, also presented an increased risk of death during the study, the researchers noted.

On the other hand, supplements do not appear to have increased the risk of death in people who lacked vitamin D in their normal diet.

In light of these results, the scientists conclude that people who have no specific dietary deficiencies should continue to benefit from nutrients in “real” food by maintaining a balanced diet high in fruits and vegetables. – AFP Relaxnews