- We naturally feel tired at two different times of the day: about 2:00 AM and 2:00 PM. It is this natural dip in alertness that is primarily responsible for the post-lunch dip.
- Man is the only mammal that willingly delays sleep. All other mammals sleep when they get tired.
- Sleep disturbance becomes greater at altitudes of 13,200 feet or more. The disturbance is caused by diminished oxygen levels and accompanying changes in respiration. It takes two to three weeks to adjust to altitude changes. This can prevent you from sleeping if you move to a totally different level of altitude.
- Exercising regularly makes it easier to fall asleep and contributes to sounder sleep. Intense exercise right before going to bed will make falling asleep more difficult.
- Divorced, widowed and separated people report more insomnia.
Sleep is just as important as diet and exercise and a lack of sleep has many side effects.
- When infants are put to bed drowsy but not asleep, they are more likely to become "self- soothers," which enables them to fall asleep on their own at bedtime and put themselves back to sleep if they wake during the night.
- Snoring is the primary cause of sleep disruption for approximately 1/5th of the population.
- People who don’t get enough sleep are more likely to have bigger appetites and more likely to suffer from obesity due to the fact that their leptin levels (leptin is an appetite-regulating hormone) fall, promoting appetite increase.