Taking a daily vitamin supplement, including just a multivitamin, raises an older woman's risk of dying from heart disease or cancer, according to a new study.
Authors of the study say it highlights concerns about long-term use of supplements and vitamins by people who don't have serious nutrition problems.
About half of U.S. adults take multivitamins.
Vitamin and supplement sales total more than 20-million dollars a year.
Researchers and nutrition experts call the new findings "puzzling" and say more research is needed.
The study appears in the journal "Archives of Internal Medicine."
(Copyright 2011 by VERTEXNews/Newsroom Solutions)