Factors affecting the use of dietary supplements by Korean adults: data from the Korean National Health and Nutrition Examination Survey III.

We investigated the use of dietary supplements among adult Korean consumers, including associations involving sociodemographic variables, lifestyle characteristics, health-related factors, and dietary supplement use. The data were derived from the 2005 third Korean National Health and Nutrition Examination data among 4,775 adults (1,983 men and 2,792 women) regarding medical examinations and diet. In general, 21.8% of the male and 32.0% of the female respondents used dietary supplements regularly. Dietary supplement users tended to reside in large cities and to have higher monthly incomes. People with bone diseases consumed 1.71 times higher (95% confidence interval [CI] 1.19 to 2.46) amounts of supplements than those without such diseases. Among dietary supplement users, female respondents expressed a preference for carbohydrates (adjusted odds ratio [OR] 3.79; 95% CI 1.33 to 10.79). The intake rates for vitamin/mineral complexes tended to increase with age (P for trend 0.007) and respondents earning higher incomes expressed a preference for minerals, vitamin/mineral complexes, and terpenes. Carbohydrate use decreased among those with higher education levels: high school graduates were 0.48 times (95% CI 0.23 to 0.99) and those with college or above were 0.24 times (95% CI 0.07 to 0.83) more likely to use carbohydrates. Nonsmokers (OR 2.63; 95% CI 1.68 to 4.13), nondrinkers (OR 1.73; 95% CI 1.09 to 2.73), and those with bone disease (OR 2.19; 95% CI 1.24 to 3.86) expressed a preference for vitamins. Those who had been diagnosed with a chronic disease showed a preference for terpenes (OR 2.81; 95% CI 1.03 to 7.68). These results indicate that dietary supplement use might be affected by certain sociodemographic, lifestyle, and health characteristics.