Early morning classes deprive students from getting sufficient sleep, according to a study by the Education Commission of the States.

Researchers said that students in middle and high school lose at least three hours of sleep a day due to early morning classes that in turn negatively affect their academic performance. Academicians have long claimed that delayed school  improves learning, reduces health risks and enhances safety in teens.

The researchers analyzed previous studies including effects of sleep loss on alertness and how late start times positively affect students. Overall, around 9, 000 high school students were involved in the study.

The researchers found that on average, adolescent students are associated with 2.7 hours of sleep loss because their biological clock compels them to late wake/sleep times. A teen required to wake up at 7:00 a.m. is equivalent to adults waking up at 4:00 a.m., and suffers from chronic sleep loss. And one week of chronic sleep deprivation leads to poor academic outcomes and heightened health risks.  

On the other hand, beginning classes later in the morning results in improved grades and attendance, and lesser traffic accidents.

Researchers said that countries like United Kingdom and New Zealand have implemented delayed start times (10:00 a.m.) at their school for older adolescents. The staff observed positive achievement and behaviors among students.

Researchers also said that shifting the start timings to later part of the day would involve challenges.

"Changing community habits based on conventional wisdom can be difficult and needs to be handled confidently. Current early start times have determined timing of other activities (bus transportation and student athletics, for example) and organizers of these activities may resist change," the researchers wrote.

Researchers urge lawmakers to consider changing high school bell timings, MLive reports.

"There are undoubtedly pragmatic reasons to avoid change. These are not reasons, however, for stakeholders to avoid considering options for reasonable and appropriate changes to school start times."

A recent University of Minnesota study found that high schools that commence at 8:30 a.m. or later allows more than 60 percent of students to get at least eight hours of sleep every day.

"Teens getting less than eight hours of sleep reported significantly higher depression symptoms, greater use of caffeine, and are at greater risk for making poor choices for substance use," the researchers wrote.