No one can attest for sure the percentage of people who sleep in the nude.
I have read from less than 10% to 33% regardless of the sex of the person.
One source says that 7% of males and 83% of females sleep in the nude. The percentage does not really matter for this readership, people who come to this site want to achieve faster their goals of getting lean.
How can sleeping naked improve your body composition? Four reasons:
1. You need to cool off at night in order to bring down the level of cortisol. Excess cortisol leads to increased pro inflammatory belly fat storage and catabolism of muscle mass, especially in the extremities. Making less cortisol at night, means making more during the day when you can put it to good use. Depending on when it is secreted, cortisol is either your friend or your enemy. When waking up or during workouts it is your friend. When you keep it around at night, it becomes your enemy.
2. If you are too hot when you sleep, your production of growth hormone suffers. You need optimal levels of growth hormone to repair all tissues in the body and also to burn fat. Healthy growth hormone production also benefits your immune system, and lowers your risk of diabetes and heart disease.
3. Besides growth hormone, melatonin is also another anti-ageing hormone, that is associated with deep restful sleep. As with growth hormone, being overly warm shuts down its production leading to disrupted sleep.
4. The same raw material that makes cortisol, pregnenolone, also makes testosterone. Hence, if you make too much cortisol, you are limiting your testosterone production! The consequences being that building muscle and burning fat becomes harder!
So here are the physiological reasons why sleeping naked can get you to a leaner more muscular body sooner.
Charles R Poliquin