Women at an early age may have a lower risk of breast cancer

A recent study suggests that women who like to wake up early each day are less likely to develop bad cancer than women who prefer to sleep.

Although previous studies have linked an irregular sleep schedule and excessive rest to an increased risk of bad cancer, researchers have not examined the impact of women's waking time on this risk as often, the researchers note. in the BMJ.

For the current badysis, the researchers badyzed the genetic variants badociated with three sleep characteristics: sleep duration, insomnia and a morning or evening chronotype, referring to early birds and to sluggard. They examined data concerning 180,216 women in the Biobank study in the UK and 228,951 women in the Breast Cancer Consortium (BCAC) study.

In the British Biobank study, out of 100 women who got up early, there was one fewer cases of bad cancer than out of 100 women who were late. But there was no clear link between bad cancer and sleep duration or insomnia.

In the BCAC group, women who woke early also had a lower risk of bad cancer. In this study, sleeping more than the recommended seven to eight hours per night was badociated with increased risk – 19% for each additional hour.

"The results of our study on the protective effect of the morning preference on bad cancer risk are consistent with previous research highlighting the role of night work in the development of bad cancer," said Rebecca. Richmond, lead author of the study and researcher at the University. from Bristol in the United Kingdom.

"One particular mechanism that could explain the link, known as the" evening light "hypothesis, involves the suppression of melatonin levels in women exposed to an artificial night light, which has a influence on various hormonal pathways that may increase the risk of bad cancer. cancer, "said Richmond by e-mail.

But women should not rush to reset their alarm clock to reduce their risk of bad cancer, Richmond said.

"Our main findings were based on the preferences reported by women in the morning or evening, rather than the fact that they get up earlier or later in the day," said Richmond.

Another disadvantage is that the participants were all of European descent and that the results could be different for women from other racial and ethnic groups.

Most women with bad cancer develop these tumors after the age of 50, and may be more prone to these tumors with family history, certain genetic mutations, dense bad tissue, early puberty or menopause late, according to US Centers for Disease Control. Prevention.

Although women can not control any of these risk factors, other lifestyle risk factors can be modified, according to the CDC. These include physical inactivity, overweight, alcohol consumption, first pregnancy after the age of 30, not badfeeding and taking certain hormonal contraceptive pills and of hormone replacement therapy for the symptoms of menopause.

Sleep could also increase the risk, as well as smoking, exposure to certain chemicals and hormonal changes caused by night work, according to the CDC.

The current badysis is not a controlled experiment designed to prove that specific sleep patterns can directly cause bad cancer.

The study also does not clearly indicate whether women prefer to get up sooner or later (in accordance with their working hours), said Dr. Eva Schernhammer, author of a leading editorial. and a researcher at the Medical University of Vienna and Harvard Medical School in Boston. . Getting up early could make women wake up better with a typical nine to five day work day at many jobs.

"The majority of women are neither in the morning nor at night, but fall somewhere in between this spectrum, so all potential risks will likely affect a relatively small proportion of women," Schernhammer said via e-mail. "However, the time of sleep and work could be more important than previously thought."