sleep and cancer

Research raises questions about the connection between cancer and lack of sleep (photo credit:

In recent years, sleep researchers have linked chronic lack of sleep with several serious health problems including obesity, diabetes, and cardiovascular problems.  And the results of a new study indicate that we may also need to add cancer to that list.  It seems that not getting the sleep you need at night may be one of the most damaging things you can do for your overall health and longevity.

The new study was conducted by researchers at the University of Chicago and the University of Louisville and recently published in the journal Cancer Research.  The goal of the study was to measure the effects of sleep deprivation on cancer.  Recent research into sleep apnea shows that those with the condition have a higher mortality rate from cancer which inspired this study’s director, Dr. David Gozal, to ask why.  To answer that question, the research team developed a set of experiments designed to gauge the affects of sleep deprivation on cancer in mice.

The study involved two small groups of mice that were housed separately for the duration of the study.  One group of mice had their sleep disrupted every two minutes which caused some of them to wake up and then fall back asleep.  This simulates the type of disrupted or fragmented sleep commonly seen in those with sleep apnea.  The second group of mice was allowed to sleep without interruption.  After one week, all the mice in both groups were injected with cells from one of two types of tumors causing them to develop obvious tumors over the following two weeks.  The sleep disruption in the first group continued for the entirety of the study.

Four weeks after the tumor cells were injected, the researcher assessed the tumor growth in each of the mice.   The mice in the first group, whose sleep was disrupted for the entire 5 week period had tumors that were twice as large as those found in the mice who were sleeping normally.

In fact, when additional research was conducted, the team found that tumors in the fragmented sleep group were also more aggressive and invasive than those in the control group.  This finding resulted from the tumor cells being injected into the thigh muscles of the mice, an area which would normally restrict the growth of tumors.  But rather than providing any natural restriction, the tumors in the fragmented sleep mice were more aggressive and invaded other tissue in the sleepy mice.

These findings help pinpoint what may be the root cause of the higher mortality rates for cancer patients who also suffer from sleep apnea.  According to Dr. Gozal, the difference results from how sleep deprivation affects the immune system.  When we aren’t getting enough sleep, our immune system is altered in ways that seem to make cancer more aggressive.

These findings will open the door for future research that may identify new treatment options and underline the importance of getting a good night sleep every night.