Researchers are still deciphering how much light at night is too much. But keeping your circadian rhythm running smoothly jibes with healthy living.
Sleep in a completely dark room. Turn off all hall and night-lights. If the glow from street lamps or commercial signs envades your bedroom, consider investing in room-drakening shades or blinds.
Shoot for nine
A new study of 7,396 Finish women found that those who slept an average of 9 or more hours a night were one-third as likely to get breast cancer as those who slept 7 to 8 hours. This is the first evidence of a relationship between sleep duration and breast cancer risk.
Choose a dim bulb
If you wake up in the middle of the night and can't sleep, don't turn on a bright light and read. Just 10 minutes of light is enough to suppress melatonin in some people. Instead l;ie in bed to see if you can drift back to sleep. If you must get up, keep the lights dim.
If you wake up in the middle of the night to go to the bathroom, resist the urge to flip on the fluorescent vanity light. Instead, keep a red light bulb in one fixture. Blue wave-lengths cast by fluorescent and halogen lights are the worst offenders. Red wavelengths, on the other hand, are the most innocuous.
Get some sun...
The circadian system needs bright light to reset itself. ten to 15 minutes of morning sunlight will send a strong timekeeping signal to the brain's clock, leaving it less likely to be confused by weaker signals from night-lights. If it's dark when you leave for work or dust when you get home, a brisk lunchtime walk will help.
And more sun as you age
In older adults, the brain's master clock, the suprachiamatic nucleus (SCN), shrinks and slows down, which make the receptors less alert to light signals. Due to eye changes, a 60-year-old gets one-third the amount of ligh that a 20-year-old gets. If you can't be outdoors as much as you'd like, throw open the blinds and position a chair near a window to maximize rays.