A study conducted by an oxford university researcher claims that forcing staff to begin work before 10 a.m. is equivalent to torturing them and making them feel sick, anxious and overworked, National Post reports.

Dr. Paul Kelley, of Oxford University, who conducted the study, said that work and school timings should fit the natural body clock of humans.

"This is a huge society issue," Dr. Kelley told the British Science Festival in Bradford. "Staff should start at 10 a.m. You don't get back to (the 9 a.m.) starting point until 55.

"Staff are usually sleep deprived. We've got a sleep-deprived society. It is hugely damaging on the body's systems because you are affecting physical emotional and performance systems in the body.

"Your liver and your heart have different patterns and you're asking them to shift two or three hours. This is an international issue. Everybody is suffering and they don't have to."

Earlier studies on circadian rhythms have revealed that the average 10-year-old cannot concentrate on academic work before 8.30 a.m. Similarly, teenagers should ideally start work at 10 a.m. and university students should start at 11 a.m.

Similarly, the study states, companies should not force employees to start work earlier as it may adversely affect their output and their health.

Dr. Kelley said that a change in school times could raise grades by 10 per cent.

He said that it was not possible to change the 24 hour cycle of the body to make it attuned to getting up at a particular time.

 "This applies in the bigger picture to prisons and hospitals," he added. "They wake up people and give people food they don't want. You're more biddable because you're totally out of it. Sleep deprivation is a torture."

Lack of enough sleep has been shown to have an impact on performance, attention and memory. Sleep deprivation can cause anxiety, frustration, anger, impulsive behavior, weight gain and high blood pressure.