Under 6 hours sleep related to 30 per cent increased risk of type 2 diabetes

Research from the University of Newcastle shows that too little sleep is associated with a significant increase in risk of type 2 diabetes.
The research process used to find the association was a meta-study, whereby researchers review results from a number of different qualifying studies to find results and trends across a large number of people. In this meta-study, 212,388 adults over the age of 45 years were reviewed.
Most participants (64.7%) reported normal sleep times of 7 or 8 hours. Participants that had 6 hours sleep or less experienced a 30% greater risk of developing insulin resistance and type 2 diabetes. The study also showed that having either significantly shorter (under 7 hours) or longer (over 10 hours) sleep times was associated with a higher rates of obesity.
The researchers noted with interest that whilst shorter sleep times were associated with greater type 2 diabetes risk, longer sleep times were not. Also of note was that sleep duration was not related to risk of cardiovascular disease.
The results are statistically significant and the researchers view the results as appearing to be clinically important. In terms of limitations of the study, the research team note that they were unable to ascertain how much short sleep duration may have been related to presence of a sleep disorder. In addition, the researchers could not be certain of whether type 2 diabetes had existed or not prior to participants reporting their sleep times.
In explanation of the results, the researchers draw attention to the fact that reduced sleep is linked with increases in grehli, the hormone which stimulates appetite, and decreases in lepti, the hormone which suppresses appetite.