Modern lifestyles tend to disrupt biological night by altering normal levels of melatonin. Researchers at the University of Colorado have found after a weekend camping trip (no flashlights, cell phones, or artificial light sources) in the mountains participant's circadian clocks shifted so melatonin levels rose earlier and they slept longer. Controls who stayed home shifted even later and woke up more groggy.
PositiveTip: Having a hard time going to sleep early? Maybe a weekend camping trip in the wilderness is what the doctor ordered!