Thursday, 12 March 2015

Inadequate Sleep, Weight Gain and Insulin Resistance

Some interesting - and scary - research about the effects of inadequate sleep have just been published. Researchers at the Weill Cornell Medical College in Qatar have found that losing as little as 30 minutes of sleep a day can cause weight gain and increase insulin resistance. Furthermore, they say that not getting enough sleep on weekdays and then catching up on sleep on the weekends isn't helpful.

Not enough sleep? Photo by GaborfromHungary
The researchers studied 522 patients who had recently been diagnosed with type 2 diabetes. The height, weight and waist measurements of the patients were measured during the study. In addition, their fasting blood sugar was recorded. The patients also had to fill out sleep diaries and calculate their weekday sleep debt.

Even at the start of the project an interesting statistic was discovered. People who had a weekday sleep debt were 72% more like to be obese than those without a sleep debt. As the study progressed, the researchers found that the longer a weekday sleep debt existed, the more serious the effects.

After six months, a weekday sleep debt was "significantly" associated with both insulin resistance and obesity. Insulin resistance is a condition in which cells no longer respond to insulin or respond to it inadequately. Insulin is a hormone that causes glucose to pass from the blood, through the cell membrane and into the cell. Glucose is the cell's energy source. Insulin binds to the cell membrane in order to trigger the entry of glucose. When cells no longer respond to insulin, the blood glucose level rises.

After the research project had lasted for 12 months, some more information was discovered. For every 30 minutes of weekday sleep debt that was reported at the start of the survey, insulin resistance was increased by 49% and the risk of obesity by 17%.

Research performed by surveys in which participants self-report data is considered to be less accurate than research involving clinical trials. It can still be valuable, though. It would be interesting to see the results of a sleep survey involving more people. 522 subjects is actually quite a small sample size for a survey. It would also be interesting to see the results of a study performed on people without diabetes.

The research suggests that lack of regular sleep causes metabolic disruption in the body. This is definitely something that I need to pay attention to. I follow the not-enough-sleep-on-weekdays and catch-up-on-sleep-on-weekends lifestyle myself. I've been thinking that I need to change this habit for some time and am pretty sure that I would feel better if I did. The new discoveries are just the prod that I need!