Media and Communication Ph.D. Dissertations


Predicting Healthy Eating Behavior: Examination of Attitude, Subjective Norms, and Perceived Behavioral Control Factors

Date of Award


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)


Media and Communication

First Advisor

Srinivas Melkote (Advisor)

Second Advisor

Louisa Ha (Committee Member)

Third Advisor

Kate Magsamen-Conrad (Committee Member)

Fourth Advisor

I-Fen Lin (Other)


Dietary behavior, as one of the major drivers of obesity, has drawn researcher’s attention in media and communication research, however, little is known about the behavior of college students. The present study, using the Theory of Planned Behavior model, investigated the factors that may influence college students’ dietary behavior. The objectives of this study were first to test the difference among college students of their behavioral beliefs, normative beliefs, control beliefs, attitude, subjective norms, and perceived behavioral control in relation to their biological sex, residence types, body mass index, and meal plan. Additionally, this study examined if attitudes toward eating a healthy diet are determined by behavioral beliefs; subjective norms are determined by normative beliefs; and perceived behavioral control is determined by control beliefs. The study also examined the predictors of healthy diet behavior. In order to address these issues, quantitative data were collected using a self-administered online survey.

The data analysis showed that females hold stronger beliefs in the consequence of not eating a healthy diet in terms of good health and quality of diet. Females perceive that it is more difficulty for them to eat healthily under the campus environment and with schoolwork stress, and females eat healthier. Comparing on-campus, off-campus rental, and off-campus with parent (s)/guardian residential types, those who live off-campus rental tend to have stronger beliefs in the outcomes of eating a healthy diet than on-campus students. Among the three groups, those who live on campus have the weakest beliefs in their control over campus environmental influence, and those who live off campus with parents/guardian have the strongest beliefs in their control over campus influence. Off-campus students are more positive in eating healthily than on-campus ones and off-campus rental students are more confident in eating healthily. Regarding meal plan, the results revealed that those who do not have mean plan in the university have stronger beliefs in the consequence of not eating a healthy diet, have stronger beliefs in their control over campus influence on their eating a healthy diet, have more favorable attitude toward eating a healthy diet, and more confident in eating a healthy diet. When comparing obese, overweight, normal, and underweight respondents, the data revealed that major differences exist between normal weight students and obese students. Normal weight students have a stronger belief in controlling their diet with schoolwork stress. They have more favorable attitude toward eating a healthy diet, and they have more positive influences from friends and family about eating a healthy diet. In addition, normal weight respondents tend to have stronger behavioral beliefs in eating a healthy diet and quality of diet than obese individuals, and normal weight respondents tend to eat healthier than obese individuals. Furthermore, overweight students care more about the behavioral consequence of not eating a healthy diet.

The data analysis also revealed that on eating a healthy diet, behavioral beliefs predict attitude, normative beliefs predict subjective norms, and control beliefs predict perceived behavioral control. The regression analysis showed that BMI, biological sex, behavioral beliefs regarding healthy diet and quality of diet, and perceived behavioral control about confidence and ability are significant predictors of healthy dietary behavior. The findings of the study imply that it is necessary and important to include the underlying beliefs in the Theory of Planned Behavior model. The model would be more comprehensive and explanatory. In addition, the study involves baseline behavioral measures, so the findings of this study can be used for strategic planning of a healthy diet media and communication campaign among college students.