Behavioral Factors Influencing the Use of Multivitamin Supplements by College Female Students: The Application of the Theory of Planned Behavior

Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Nutrition and Food Systems

First Advisor

Mary Kay Meyer

Advisor Department

Nutrition and Food Systems


Each year approximately 2,500 to 3,500 babies in the US are born with a variety of neural tube defects comprising a significant public health problem in terms of mortality, morbidity, medical cost, and human suffering. Studies conducted in recent years clearly showed a direct relationship between an inadequate folic acid status and neural tube defects. As a result, public health officials recommended that women capable of becoming pregnant take folic acid-containing supplements on a daily bases. Unfortunately, the compliance with the recommendation is low. This study attempted to identify factors important to undergraduate female college students ages 18 to 25 regarding the use of multivitamin supplements within the framework of the Theory of Planned Behavior. A convenience sample of 196 students with a mean age 21.2, SD = 1.7 years was used in this study. The sample included 100 African American (51.02%) and 96 Caucasian (48.98) students. The results show that the correlation coefficient of the linear combination of attitude, subjective norms, and perceived behavioral control was significantly related to behavioral intention R = 0.78 indication that approximately 60 percent of variance in behavior intention was explained by these three variables (p < 0.001). The results also show that behavioral intention significantly predicted the use of multivitamin supplements accounting for approximately 43 percent of variance (0 < 0.001). Other variable of the Theory of Planned Behavior did not significantly contribute to the explanation of variance in behavior above and beyond behavioral intention. Consistent with the results of the present study educational campaigns targeting populations of college-age females to take multivitamin supplements should include specific attitudinal factors including improvement of health, getting nutrients one does not get in one's diet, feeling and looking better, and having more energy. Also, such campaigns should include targeting specific normative factors including family, doctor, and peers.