Being "in the morning" could reduce the risk of breast cancer – 07/11/2018

British research presented at the National Cancer Research Institute's 2018 conference shows that women who prefer the morning have a lower risk of bad cancer than those who are more at night.

This extensive study, conducted by Dr. Rebecca Richmond of the University of Bristol with the help of researchers from the Universities of Manchester and Exeter and some American and Norwegian researchers, took into account data concerning 409,166 women to find out whether the morning or evening preferences contributed to the development of bad cancer in women.

The participants included 180,215 women from the UK Biobank project – a large long-term study that takes into account genomic data from around 500,000 people – and 228,951 women undergoing bad cancer research for the first time. International Breast Cancer Consortium (BCAC), which has the largest amount of bad cancer data in the world.

The scientific team used a method called Mendel's randomization, which uses genetic variants badociated with possible bad cancer risk factors, such as sleep characteristics, to see if they could contribute to causing this disease. This type of badysis offers more reliable results, so if an badociation is found, it is more likely to have a direct link.

Data from the BCAC group showed that women who were older in the morning had a 40% lower risk of bad cancer compared to more "evening" participants.

They also found a causal link between sleeping longer and an increased risk of bad cancer.

The badysis of the UK Biobank study participants gave similar results, the researchers said that the preference for morning activities reduced the risk of this type of cancer by 48%, although a link between insomnia or duration of sleep and the risk of bad cancer was less obvious for this group.

The scientists concluded that the study offered concordant evidence of a protective effect for people who prefer morning in relation to the risk of bad cancer.

Dr. Richmond commented: "We would like to extend our work to investigate the mechanisms behind these findings, as the estimates obtained are based on questions about morning or evening preferences rather than people getting up earlier. or later in the day – in other words, changing your habits may not affect your risk of bad cancer – it may be more complex than that. "

"However, the results show a protective effect in morning women compared to bad cancer in our study, they are consistent with previous research, which highlights the role of night work (…) as a risk factor for bad cancer. "

The Congress of the National Cancer Research Institute was held November 4-6 in Glasgow. The summary of the study presented at the conference is available online.