Working through the night rather than sleeping can lead to an increased risk of breast cancer, according to a recent University of Georgia study.
According to the research findings, staying up all night means a person is receiving artificial light during the time they should be sleeping. On a biological level, this alters the way the body secretes melatonin, an important regulator of one’s sleep-wake cycle known as circadian rhythm.
A disruption in melatonin leads to an increased risk of breast cancer, according to the study, something that can be especially applied to college students.
“In general, cancer is a disease that affects older individuals, but there’s a lot of other adverse health effects that are related to circadian disruption,” said Sara Wagner Robb, an assistant professor of epidemiology in the College of Public Health. “Even staying up late, pulling all-nighters and staying out late downtown can disrupt circadian rhythms.”
Chunla He, a biostatistics graduate student in the UGA College of Public Health, conducted the research by analyzing 28 studies that included risk factors for developing breast cancer.
“The important take-home message is that recent research, including what we found, has shown that circadian disruption is an important risk factor for cancer, specifically breast cancer,” said Robb, He's mentor.
Women in the U.S. have a 1 in 8 chance of being diagnosed with breast cancer during their lifetime, according to an American Cancer Society report. Workers who take on night shifts should be made aware of their higher risk of developing breast cancer, Robb said.
“People who work shifts — flight attendants, for example — should really understand that and take measures to protect themselves,” she said.
Robb said those who have an increased risk should keep their circadian rhythms as normal as they can, even if their job makes them work during the night.
Brittany Futch, a senior public relations and English major from Lawrenceville, said she had never considered the long-term health effects of pulling an all-nighter.
“This finding is really nerve-wracking because they warn us about a lot of other side effects from sleep deprivation, but I never thought of breast cancer being one of them,” she said.
Protective measures for those who have to work at night include wearing sunglasses during the day and taking melatonin supplementation. Implementing an earlier bedtime can also be beneficial to one’s health, Robb said.
Despite their findings, the study's authors recommend further research be conducted on the causes of breast cancer.
“Studies that follow people who are in these circadian-disrupting occupations over long periods of time to see whether or not they get cancer would be really important to confirm these findings,” Robb said.