Sleep is the panacea of our time. A vast and growing body of research shows that when we get good sleep, good things happen inside our bodies.
When we don't get good sleep, though, the opposite can occur, with poor sleep linked to all kinds of health problems.
And it's not just our health that's hurt by a lack of sleep.
In recent times, multiple studies have investigated the effects poor sleep has on adolescents, with many finding better sleep can improve students' overall well-being, while suggesting a lack of it might impact young people's academic grades.
In a first-of-its-kind study published in the Journal of Political Economy, researchers set out to test that question, and discovered a way to influence college students that not only boosted their sleep but also their college grades.
"Sleep deprivation is extremely common among young adults, yet universities have struggled to find affordable ways to improve student performance," health economist Osea Giuntella from the University of Pittsburgh told ScienceAlert.
"To our knowledge, this is the first field experiment to show that improving sleep causally improves academic performance."
In their research, Giuntella and fellow researchers studied a group of 1,149 student participants over several waves of the experiment.
At baseline, the students were getting on average just 6.6 hours of sleep each night, and sleeping less than 6 hours on 29 percent of weeknights.
"What excites me most is that these are relatively simple interventions that could be adapted and tested in many different settings." – health economist Osea Giuntella
In the intervention stage, all the students were given wearable Fitbit health trackers (to monitor their sleep), and were randomly assigned to one of two groups.
The treatment group was encouraged to get at least 7 hours of sleep on weeknights, received personalized bedtime reminders, and were offered a modest cash incentive ($4.75 per night for four weeks) if they met their nightly sleep goal.
By contrast, the control group just wore their Fitbits, but weren't instructed or rewarded for modifying their sleep patterns.
"We were interested in two main questions," Giuntella told ScienceAlert. "First, could a simple behavioral intervention help students develop healthier and more persistent sleep habits?
"Second, while many studies had documented a strong correlation between sleep and academic performance, there was very little causal evidence using wearables and real-world settings showing that improving sleep actually leads to better educational outcomes."
Based on the results, we now have our answer.
During the intervention, the students in the treatment group ended up sleeping more, showing a 26 percent increase in the share of nights students met their 7-hour sleep goal, with sleep duration overall increasing by 19 extra minutes a night.
Even after the intervention ended, these students still slept more than they did at baseline, although the effect diminished to just 8 extra minutes of sleep once the rewards and reminders ceased.
"After the first wave of the study in 2019, we had a good sense that the intervention was improving sleep and that some of the effects persisted after the incentives ended," Giuntella said.
"But what really convinced us we had an important finding was when we linked the experimental data to students' official university transcripts and found improvements in GPA."
Those results showed that students in the intervention group improved their average course performance by 0.075–0.089 grade points in their classes during the intervention semester, with a persistent effect of similar magnitude being seen in the following semester.
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While the effects are relatively modest and warrant replication in further studies, the fact that the sleep experiment demonstrated improved academic performance is an extremely promising finding.
Not to mention that the GPA improvements seen here either outperformed or were comparable to academic gains delivered by scholarship-style financial incentive programs – but at a fraction of the cost, the researchers say.
"What excites me most is that these are relatively simple interventions that could be adapted and tested in many different settings," Giuntella said. "Not only universities, but potentially schools and workplaces as well."
The findings are reported in the Journal of Political Economy.
This article was fact-checked by Rachel Garner and edited by Rebecca Dyer. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know.