Working night shifts has no association with developing breast cancer, according to an Oxford University research, which studied 1.4 million women that work on this schedule.

The new finding is contrary to what previous studies which proved that working nights cause sleep deprivation, risk of diabetes, negative metabolic changes and even depression.

No links between breast cancer and night shifts 

However, the researchers determined that women who work on a normal schedule, and those who worked on night shift for years, have exactly the same incidents of breast cancer, which proves the non-existent link between this breast cancer and working during late hours.

Associate professor Dr. Ruth Travis said to the Daily Mail, "We found that women who had worked night shifts, including long-term night shifts, were not more likely to develop breast cancer, either in the three new U.K. studies or when we combined results from all 10 studies that had published relevant data."

According to the BBC,this study is good news, as 14 percent of women in the U.K. have worked on this shift, and two percent have worked for two decades and even more.

The previous research

This study was published in the Journal of the National Cancer Institute, and belies the 2007 research, in which based on a combination of animals and lab studies, a World Health Organization committee explained that working night shifts would increase the risk of breast cancer.

"Research over the past years suggesting there was a link has made big headlines, and we hope that today's news reassures women who work night shifts. Breast cancer is the most common cancer in the U.K. and research to fully understand the different risk factors is vital so that we can give women clear health advice," said Sarah Williams, health information manager at the Cancer Research U.K.