During the study, researchers analyzed data 180,215 women enrolled with the UK Biobank project and 228,951 women who were part of a genome-wide association led by the International Breast Cancer Association Consortium.
The research report revealed that morning larks are 40 to 48 percent less likely to develop breast cancer when compared to their nocturnal peers. The study also found that women who slept for more than seven hours had a 20 percent increased risk per the additional hour they sleep.
The researchers, during the study, used a genetic method known as Mendelian randomization, scientists studied the cancer risks independently of confounding factors like alcohol or smoking.
Rebecca Richmond, the lead author of the study revealed that this new finding could have serious implications on women who are working in night shifts.
"These findings have potential policy implications for influencing sleep habits of the general population in order to improve health and reduce the risk of breast cancer among women. We would like to use genetic data from large populations to further understand how disrupting the body's natural body clock can contribute to breast cancer risk," said Rebecca.
However, she also admitted that more advanced studies should be conducted to understand the real reason that determines the connection between waking up early or late and breast cancer diagnosis.
"We would like to use genetic data from large populations to further understand how disrupting the body's natural body clock can contribute to breast cancer risk. We would like to do further work to investigate the mechanisms underpinning these results. In other words, it may not be the case that changing your habits changes your risk of breast cancer; it may be more complex than that," said Rebecca.
Even though the result of this study report is yet to be published in a peer review journal, it was presented at the National Cancer Research Institute Conference in Glasgow last Tuesday.