Determinants of supplement usage.

Abstract

As the use of supplements is growing, this study examines the determinants of vitamin and herbal supplement usage. Instead of treating these as all-encompassing categories, they are broken into specific vitamins and herbs and compared to see if users are different. A measure of frequency of vitamin use is also created. Logistic and ordinal logistic regressions are run on a sample of 24,834 from the National Health Interview Survey (NHIS) 2000. Women are generally more likely to use supplements than men. Non-Latino Whites are generally more likely to use supplements than non-Latino Blacks and Mexicans. However, despite these general trends, it proves fruitful to break up supplement use into smaller categories. The data provide some evidence that determinants vary by particular supplement. However, including a measure of frequency does not change the picture much. Considering this, more information is needed on why people use particular supplements and what their sources of information are.