Want to earn your degree

Want to earn your degree? Get enough sleep, eat breakfast, and stay away from fast food

As a group, college students are surprisingly understudied regarding their health behaviors and habits and their impact on students’ academic success or failure. Various surveys collect data on students during primary and secondary education (K-12). For example, the national Youth Risk Behavior Survey (YRBS) from the Centers for Disease Control and Prevention (CDC) consists of a set of surveys that collect data from students in grades 9 through 12 every second year. However, once young adults leave the K-12 system, they cannot be reached easily anymore. Therefore, it doesn’t surprise that most published research on the correlation of eating habits and associated GPA/grades has focused on students in Pre-K through high school. On the other hand, there are only a limited number of studies concerning college students.

Nonetheless, these studies consistently provide evidence that poor eating habits adversely impact academic performance, while healthy dietary behaviors are favorable predictors of academic success. Healthy eating habits have been shown to positively influence academic performance, with the quality of students’ diets appearing to be the main factor for this effect. The importance of sleep, however, has been stressed in numerous studies. Sleep is not only a necessity for biological functioning but also a vital component for maintaining cognitive roles, memory consolidation, decision-making, and learning in general. Sleep quality and quantity are among the most researched health behaviors in connection with the academic performance of university students, and there is a consensus that both can affect students’ grades.

My research project, “Student health behavior and academic success,” started in 2016. Together with a group of undergraduates, I looked at 28 health behaviors and habits and their impact on the academic performance of undergraduate students at our university. The behaviors we selected were from five categories: 1) sleeping habits, 2) working, 3) physical activity, 4) eating habits, and 5) alcohol, tobacco, and drug consumption. Based on data provided by more than 600 students, we found:

The only healthy eating habit that positively impacted students’ GPA was eating breakfast. Students who ate breakfast five days per week or more had significantly higher GPAs than those who skipped breakfast or had breakfast on less than four days per week.
Consumption of fresh fruit, fruit juice, vegetables, green salad, and milk didn’t improve students’ grades.
Increased fast food consumption was correlated with a lower self-reported GPA. Students who had fast food at least seven times in the week prior to responding to our study had significantly lower GPAs than students who had not eaten any fast food or only 1-3 times in the past week.
Students who slept less than four hours or more than nine hours per night had lower GPAs than those who slept six to eight hours per night. However, it did not matter what time students went to bed as long as they got a sufficient amount of sleep.

The number of hours full-time students work negatively affects their academic performance. Students working more than five hours per week reported lower GPAs than students who didn’t work or up to five hours per week only.
Being physically active pays off! Students who considered themselves as not physically active at all had significantly lower average GPAs than physically active students. Also, respondents who engaged in exercises to strengthen or tone their muscles, such as push-ups, sit-ups, or weightlifting, reported marginally higher GPAs than students who did not engage in such exercises.
The self-reported GPAs for students who had consumed alcoholic drinks, tried cigarette smoking, and used electronic vaping products were marginally lower than those who had not engaged in any of these behaviors before. However, we did not find an association between the number of alcoholic beverages consumed in the past 30 days and GPA.
The only drug used by a substantial number of respondents in this study was marijuana, with 44.2% of participants responding with ‘yes’ to the question “Have you ever used marijuana?”. While we did not find an association between marijuana use frequency (i.e., number of days marijuana used in the past 7 days) and GPA, our data show that students who answered the question with ‘yes’ reported lower GPAs compared with students who answered with ‘no’.

Still, the effect sizes for these health behaviors were low overall. Even though there is a relationship to the average GPA, the variables do not explain the variation in GPA scores. For example, although self-reported GPA differs significantly by hours of sleep per night, only 5.0% of the variation in the GPA scores can be explained by this factor alone.

To sum it all up, we can say that most health behaviors and habits only have a marginal effect on students’ academic success or failure. Staying away from fast food is more important than eating healthy food (no more broccoli!!!), but skipping breakfast regularly is a bad idea, as is not getting enough sleep or trying to hibernate through college.

You can read the published research here and here.