Regan L. Bailey of the National Cancer Institute, part of the National Institutes of Health, in Bethesda, Md., and colleagues analyzed the motivations of U.S. adults for their use of dietary supplements.
The researchers examined data from almost 12,000 adults in the 2007 to 2010 National Health and Nutrition Examination Survey.
The study found 45 percent said they took dietary supplements to improve their health and 33 percent said they took supplements to maintain their health.
Thirty-six percent of women said they took calcium supplements for bone health and men 18 percent reported supplement use for heart health or to lower cholesterol.
The study, published in the journal Internal Medicine, also found 23 percent of those adults who used supplements did so on the recommendations of a healthcare practitioner or doctor.
"Given the widespread use of dietary supplements for health promotion and maintenance, increased clinical research efforts are warranted to address safety and efficacy," study authors wrote in the study.