Participants in the study sample were more likely to represent racial and ethnic minorities and were younger than the total student population at the two schools. At the 2-year community college, 18%, 61%, and 21% of study participants were under 19 years old, 19 – 24, and over 24, respectively, compared with 6%, 54%, and 41% of all enrolled students. Study participants from the 2-year college represented more racial/ethnic minorities (41% white, 34% African-American, 22% Asian, 12% other), compared to all enrolled students (62% white, 20% African-American, 12% Asian, 4% other). Gender did not differ appreciably (53% participants were female vs. 55% of all students). At the 4-year public university, 11%, 85%, and 4% of study participants were under 19 years old, 19 – 24, and over 24, respectively compared with 10%, 79%, and 11% for all enrolled undergraduate students. Study participants from the 4-year university represented more racial/ethnic minorities (52% white, 8% African-American, 36% Asian, 10% other), compared to all enrolled students (70% white, 4% African-American, 8% Asian, 18% other. Gender did not differ (52% participants were female vs. 52% of all students).
Thirty-five percent of participants were classified as frequent label readers (reporting nutrition label viewing “always or almost always” or “often”). This percentage is on the low end of the range of self-reported rates of label use (typically about 40-60%) presented in other studies (see reference 27
for review). However, the mean response to the label use question in the present study was 2.3 on a 1-4 scale, which is similar to the mean of 3.3 on a 5 point scale (1=never, 5=always) reported by Misra and colleagues in their 2007 study of label use among college students in Texas (5
), both of which suggest that the average college student uses nutrition labels sometimes. In that participants in our study tended to be somewhat younger than those included in most previous nutrition-label research, the slightly lower rate of frequent label use reported here relative to the rates summarized in the Grunert and Wills review (27
) is consistent with evidence that label use increases with age (27
Consistent with our a priori hypotheses, independent samples t
-tests revealed that frequent nutrition label readers showed higher rates of engaging in each of the 8 healthy dietary behaviors (significantly higher for eating fruits/vegetables, fiber, and a vegetarian diet, as well as limiting fast food and added sugar; p<0.001) compared with the infrequent label readers (see ). In addition, consistent with our hypotheses and with previous research (5
), frequent label readers demonstrated greater nutrition knowledge than infrequent label readers. Estimates of how many calories and fruit and vegetable servings they needed in order to be healthy provided by frequent label readers were significantly nearer to the true recommendations (by more than 200 calories and approximately half of a serving each of fruits and vegetables; all p
’s < 0.001) compared to the estimates provided by infrequent label readers.
Comparison of demographic and dietary variables among frequent and infrequent label readers
Linear regression analyses (see ) revealed that 1) attitude toward preparing healthy meals was a statistically significant predictor of the healthy eating composite score; 2) attitude toward preparing healthy meals significantly predicted nutrition label use; and 3) when included in a regression model together, both attitude and nutrition label use significantly predicted the healthy eating composite score, suggesting possible partial mediation by nutrition label use of the relationship between attitude toward healthy eating and healthy dietary practices.
Test of Mediation of the Relationship between Attitude toward Healthy Eating and Overall Dietary Quality by Nutrition Label Use
A Sobel’s test of partial mediation (25
produced a z-score of 4.80, indicating that nutrition label use was indeed a significant partial mediator of the relationship between attitude toward healthy eating and healthy dietary practices.
In addition, nutrition label use significantly predicted the healthy eating composite among both attitude-based groups of participants (i.e., those who agreed that it was important to prepare healthy meals [b(se) = 0.27(0.05), β = 0.20, p<0.001 and those who did not (b(se) = 0.16(0.07), β = 0.12, p=0.02)]).
The role of nutrition label use as a partial mediator between attitude toward preparing healthy meals and healthy dietary practices indicates that consumers with an inclination to make healthy dietary choices may be utilizing nutrition labels as one way of putting their health preferences into action – a possibility supported by previous research demonstrating that health concerns predicted frequent label use among college students (29
). The present analyses indicated that higher levels of label use were related to greater engagement in healthy eating behaviors not only among those participants with healthy eating attitudes, but also among those who did not
believe it was important to prepare healthy meals. Although provision of nutrition information on its own has not been shown to be highly successful in changing dietary behaviors (30
), accurately understanding nutrition information may be one of the many contributors to dietary intake, and may operate independently of nutrition-related attitude. These findings underscore the need for accurate, readily accessible, and understandable nutrition labeling on foods in the US.
Although the present study is the first of its kind to indicate that nutrition label use partially mediates the relationship between attitude and diet among young adults, there are important limitations to address. Participants comprised a diverse sample of both traditional and non-traditional college students; however, college students may differ in numerous ways from the larger population of young adults. Thus, these results may not generalize to young adults beyond 2- and 4-year college students. The participants were also recruited via convenience sampling, and responders were more likely to represent racial and ethnic minorities and were younger than the total student population at their respective colleges; although not assessed, it is possible that responders differed from non-responders in additional ways. It is also important to note that this analysis is limited by a cross-sectional design; thus, it is not possible to determine from these data whether attitude toward healthy meals preceded nutrition label use and dietary behavior. Longitudinal research could help to clarify this temporal ordering, and a prime opportunity for prospective research in this area is emerging as new nutrition labels are beginning to appear on the front of food packages in the United States (32
). Measuring consumers’ health-related attitudes before front-of-pack labels are ubiquitous and assessing attitudes again after a period of naturalistic exposure to the new labels could facilitate a clearer temporal understanding of the role of label use in linking attitudes to behavior.