During non-REM sleep, metabolic rate and brain temperature are lowered to deal with damages that may have occurred during time of wakefulness.
[2] Several studies suggest that the association between sleep loss, obesity, and diabetes risk, may be driven by several factors.
Three main examples are altered glucose metabolism, increased appetite, and lower energy expenditure.
[4] Sleep loss can affect the basic metabolic functions of storing carbohydrates and regulating hormones.
Researchers from the University of Chicago Medical Center followed 11 healthy young men for 16 consecutive nights.
When the participants were tested after sleep deprivation, they took 40% longer than normal to regulate blood sugar levels after a high-carbohydrate meal.
[5][medical citation needed] Increased cortisol levels in turn induce insulin resistance, resulting in raised blood glucose.
[4] It has also been shown that when slow-wave sleep was suppressed for three nights, young healthy subjects were 25% less sensitive to insulin.
When sleep deprived, the metabolic system will be out of balance, which will ultimately affect the dietary choices people make.
In a study with 3000 patients, it was found that men and women who sleep less than 5 hours have elevated body mass index (BMI).
[11] Studies have also shown that detrimental effects on muscle protein synthesis caused by sleep loss can be mitigated by exercise.