A few days ago, a story was reported by Reuters Health (www.reutershealth.com) which I read on Regina Leader-Post (http://www.leaderpost.com/health/Sleep+deprivation+tied+weight+gain/1686030/story.html) about how sleep loss can affect weight gain and obesity.
There is a growing body of research that shows that people who sleep too little or who have poor quality of sleep are more likely to be over-weight or obese. The new research from the University of Chicago (www.uchospitals.edu) has a new and interesting implication: that you might be able to lose weight if you are sleep deprived, but it might not be fat that you are losing. The study is limited by small sample size, but it indicates that weight loss during periods of sleep restriction may be due more to loss of lean body mass than to loss of fat. Fat represented 57% of the weight loss when the nine subjects slept 8.5 hours on average in a 2 week period , but only represented 26% of the weight loss when they slept 5.5 hours during another 2 week period. The total amount of weight they lost in each period was practically the same.
The other study mentioned in this article showed what many population studies have showed: Those people who sleep less, gain more weight. There are numerous population studies that show that people who sleep fewer than 6 hours or have sleep that is disrupted by disorders such as sleep apnea are much more likely to be over-weight or obese.
Laboratory research, much of which was done at University of Chicago, points to the explanation for this. When your sleep is disrupted or restricted, then your metabolic rate is slowed, your appetite hormones are not functioning properly(making you hungrier) and your ability to regulate your glucose and insulin is impaired, not to mention that you just have no energy to exercise or take the time to prepare nutritious food.
