Working the third shift is like putting the body "into chaos" and has been linked to several diseases and long-term health concerns, according to new research.

At night, the human body's internal clock is expecting sleep, reserving energy for work during the day. According to BBC News, a new Sleep Research Center study says being awake and active at night causes surprising damage to the body.

The researchers found offsetting the internal body clock can affect mood changes, brain function, athletic ability, body temperature and even hormones. However, the study, published in the journal Proceedings of the National Academy of Sciences, did not track night workers who were used to such a schedule. For their work, the researchers tracked 22 people who were abruptly put into working night shifts instead of a normal workday.

"Over 97% of rhythmic genes become out of sync with mistimed sleep and this really explains why we feel so bad during jet lag, or if we have to work irregular shifts," study researcher Dr. Simon Archer, of the University of Surrey, told BBC News.

Blood tests on the participants showed their genes were actually programed to be more active at certain times of day. When their internal clocks were disrupted, the workers' genes were left out of sorts.

"It's chrono-chaos. It's like living in a house," another researcher, Derk-Jan Dijk, told BBC News. "There's a clock in every room in the house and in all of those rooms those clocks are now disrupted, which of course leads to chaos in the household."

Previous studies have linked insufficient sleep at the wrong part of the day with type 2 diabetes, obesity, heart attack and stroke.

"The study indicated that the acute effects are quite severe," Hugh Piggins, an expert on the internal body clock at the University of Manchester, told BBC News. "It is surprising how large an effect was noticed so quickly, it's perhaps a larger disruption than might have been appreciated."