Scientists have found further evidence, in a study of mice, linking chronic disruptions in sleep to cancer and weight gain.
The researchers say there are so many factors in this type of study in humans that it is tricky to find solid associations.
However, the study in mice found that animals with a predisposition to breast cancer grew tumours eight weeks earlier than normal when they experienced disrupted sleep patterns and gained 20% more weight.
Those who work outside of a daily 9 am to 5 pm schedule or have frequent jet lag have been found to be at an increased risk for everything from weight gain to cancer.
In the journal Current Biology, researchers at the National Institute for Public Health and the Environment in the Netherlands and at the Erasmus University Medical Centre studied female mice with a genetic predisposition to breast cancer.
Typically these mice will develop breast cancer in 50 weeks but onset was eight weeks earlier when the mice experienced sleep disturbances.
These mice also gained about 20% more weight.
“The conclusion is that chronic changes in light schedules are a driving factor for breast cancer development, weight gain, and other metabolic problems,” says senior study author Bert van der Horst of Erasmus University Medical Centre.
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