At the Annual Meeting of the Associated Professional Sleep Societies, there was a research study that concluded that body mass index (BMI), an indicator of obesity, correlated with self-reported days of insufficient sleep per month.
The researchers studied more than 380,000 U.S. adults via telephone health survey. The asked participants how many of the last 30 days did the person feel like they did not get enough rest or sleep. The number of days of insufficent sleep steadily rose as the BMI increased. Normal weight participants (37% of those studied) reported 7.9 days of insufficient sleep per month. Morbidly obese participants (3.5% of those studied) reported 11.1 days of insufficient sleep per month.
After adjusting for demographic variables, physical activity, and smoking, those with morbid obesity were 1.8 times more likely to have at least 14 days of insufficient sleep in the past 30 days.
A spokeswoman from the CDC said that the implications of this study is that insufficient sleep should be addressed in weight-reduction programs, and excess weight should be considered in developing programs to address sleep disorders. The spokeswoman did not attempt to say that insufficient sleep causes obesity.
I have some issues with this research. One is that it is a telephone survey with no objective data from a clinician or testing. Patients who report that they did not get enough sleep could be getting the right quantity of sleep, but just the wrong quality of sleep. Obstructive sleep apnea, which is associated with obesity can rob people of sleep quality, no matter how much they slept. It is not clear the researchers addressed this comorbidity. Also, the percentage of participants that were morbidly obese was over ten times smaller than those with normal weight, so that could skew the results.