The results showed that the participants' abilities to regulate their blood sugar levels became so impaired that they may have developed diabetes had the experiment continued longer, according to the researchers."Glucose levels were higher for a longer time, and even rose to prediabetic levels in some participants," wrote the authors in their study, In the study, researchers conducted blood tests to measure levels of several hormones, including insulin, cortisol (which is associated with stress), and leptin and ghrelin (which are associated with regulating appetite).

They found that the impaired sleep schedule led to a 32 percent reduction in the amount of insulin released in the body after eating. A reduction in insulin levels is one explanation for how sleep disruption or deprivation may lead to diabetes, said Lisa Rafalson, a professor of pediatrics and family medicine at the University at Buffalo.

The new findings cast doubt on another idea — that an increased appetite stemming from sleep loss may also explain the heightened diabetes risk. Researchers have suggested that insufficient sleep leads to higher levels of the hormone ghrelin, which increases appetite, and lower levels of leptin, which signals "fullness," Rafalson said. But in the new study, researchers did not see these changes in hormone levels.

Researchers need to figure out whether there is a solution to preventing these increases in diabetes risk aside from sleeping more, Fonseca said."The reality is a lot of people who are sleep-deprived are sleep-deprived because of the nature of their occupation or work.