new study suggests working shifts at night can be damaging to one's health. In particular, it increases risk of several cancers, diabetes, mental illnesses, and various heart diseases. Researchers from Sleep Research Centre at U.K.'s University of Surrey discovered that many genes in body needed to follow regular 24-hour cycle, during which body sleeps at night. If this cycle is broken, up to 1,500 genes could get damaged, eventually resulting in potentially life-threatening diseases. Professor Derk-Jan Dijk said: " study has important implications because we now need to discover why these rhythms exist and think about consequences of that." human body has around 24,000 genes. Many of these switch off if body does not follow regular sleeping pattern. This can cause parts of immune system to become less efficient, making us more susceptible to illnesses. Study co-author Dr Simon Archer said: "Over 97 per cent of rhythmic genes become out-of-sync with mistimed sleep, which really explains why we feel so bad during jet lag or if we have to work irregular shifts." Dr Dijk said that despite results of research, it would be difficult for people to change their lifestyles. He explained it was difficult for society to function without people working night shifts, but said people needed to understand dangers and "mitigate impact".