The results of this study provided evidence that class-based nutrition education was a viable mechanism to use to help college students make positive changes in soft drink and milk consumption. Previous literature has demonstrated that there have been several studies using college nutrition courses to motivate overall dietary changes [23, 24]. Results of this research indicated that nutrition courses increased nutrition knowledge but did not promote dietary changes. On the other hand, a study using a college nutrition science course to prevent weight gain in freshmen revealed that class-based nutrition education may help college students translate nutrition knowledge into dietary changes . Overall, prior research on interventions targeting college students' dietary behaviors suggest a need to develop curriculums targeting specific nutrition behaviors in college students
After the intervention, overall total soft drink consumption had significantly decreased from baseline. The decrease in total soft drink consumption was mainly due to the reduction in regular soft drink consumption because diet soft drink intake did not decrease as a result of the intervention. The general nutrition class designed to increase the awareness of importance of nutrition in prevention of chronic disease through the combination of traditional lecture with interactive activities may have encouraged the students to reduce soft drink consumption as a part of healthy eating practices. Although it is still debated whether soft drink consumption is associated with increasing obesity rates or decreased milk consumption, it is evident that soft drink consumption has been linked to some negative life style and dietary patterns [26–29]. In a cluster study, Kvaavik et al. found that soft drink consumption could be a marker of unhealthy eating behaviors  indicating that reduced intake of soft drink in the current investigation may reflect increased overall diet quality by class-based nutrition intervention.
It should be noted that the amount of soft drinks consumed before the intervention was lower than the results reported by other researchers [30, 31] who reported daily soft drink intake of young adults between 11 and 14.4 ounces. There are several reasons to explain this discrepancy. In a study of adolescents, Bere et al.  reported that the participants who planned to receive college education showed lower odds of drinking soft drink. Cullen et al.  also found that lower parental education was associated with higher consumption of soft drinks. This data perhaps suggests that lower soft drink consumption in the current study may have been due to the higher education level of the participants, college students, compared to the study population, a mixture of both college students and young adults not enrolled in college, used in the previous studies .
A second positive finding of this study is that, although total milk consumption did not increase significantly between the genders, females increased their total milk consumption by increasing fat free milk intake while maintaining their low fat milk intake at the same level. Daily calcium intake contributed by milk consumption in females was 156.75 mg at the pretest and 233.0 mg after the intervention. This indicates that only 19% of total calcium intake was coming from milk before intervention and 25% after intervention. This is an encouraging finding because females are at an increased risk to develop osteoporosis in later life if calcium intake is compromised during adolescence and young adulthood. Meanwhile, males switched their milk choices from low fat milk to fat free milk since their total milk consumption did not change, which may demonstrate males may not recognize osteoporosis as an immediate danger due to a broad notion that osteoporosis an "old woman's disease" . It may be that the males chose fat free milk over low fat milk in an attempt to reduce fat intake, which was an important educational component in the classroom lectures and projects. However, it should be noted that, even after the intervention, milk and calcium intake was still much lower than the recommended levels, 3 cups per day by MyPyramid  or 1000 mg  for both genders at pre- or post-test, although total milk consumption increased in females after the intervention. This finding underscores the necessity of nutrition intervention specifically designed to increase calcium intake in college students.
The positive correlation between dietary calcium and milk intake supports the idea that increasing milk consumption is a desirable way to encourage calcium intake to promote adequate bone health.
Over the last two decades, several researchers have reported that a reduction in milk intake coincides with an increased consumption of soft drinks consumption and hypothesized that soft drink has displaced milk [6, 15]. However, in agreement with the previous finding by Storey et al. , the current study revealed no association between soft drink consumption and milk intake at either baseline or posttest, perhaps suggesting that soft drink consumption did not displace milk consumption in this population. This finding may imply that educating individuals to decrease soft drink consumption is not going to directing increase dairy consumption and that further dairy education needs to be addressed to ensure an adequate consumption of dairy products other than milk.
A limitation of this study is that a convenience sample without a control group was used. Therefore, the study population may not represent traditional college students. In addition, possible confounding factors, such as seasonal variation in beverage consumption, were not controlled for.
In conclusion, class based nutrition education intervention which focused on the prevention of chronic diseases has the potential in college students to reduce soft drink consumption and to increase milk consumption, specifically fat free milk, in female students and to alter milk choice in males from low fat milk to skim milk. Using this type of intervention in a general nutrition course may be an effective approach to motivate changes in eating behaviors in a college setting. Considering gender differences in changes in milk intake, future intervention programs may require different strategies for males emphasizing osteoporosis risk in men and the importance of osteoporosis prevention at earlier stages of life.