The use of dietary supplements has exploded in the United States in recent decades . Folic acid , vitamin B6 , magnesium , zinc and copper pose an increased risk . Iron was most strongly linked to an increased risk of earlier death -- calcium was the least . Calcium was the only supplement associated with a lower risk of death during the study . In a study published last year in JAMA Internal Medicine, researchers found that people who took multivitamins or other forms of folate had about twice as many deaths from heart disease than those
The use of dietary supplements has exploded in the United States in recent decades . Folic acid , vitamin B6 , magnesium , zinc and copper pose an increased risk . Iron was most strongly linked to an increased risk of earlier death -- calcium was the least . In a study published last year in JAMA Internal Medicine, researchers found that people who took multivitamins or other forms of folate had about twice as many deaths from heart disease than those