In 2012, the American Medical Association (AMA) adopted a new policy stating that nighttime light exposure is hazardous to human health.
“The primary human concerns with nighttime lighting include disability glare and various health effects,” a summary of the AMA’s policy read. “Among the latter are potential carcinogenic effects related to melatonin suppression, especially breast cancer.”
Even low levels of light, the report said, could suppress the production of melatonin, a hormone that’s secreted at night, which signals for our bodies to sleep and can also suppress the growth of tumors.
Modern day life, with our electronic devices, fluorescent lighting and busy schedules, can mean many of you are struggling to get sufficient sleep.
A sleep study evaluating 1,741 men and women over a 10-14 year period found that men who slept fewer than 6 hours per night had a significant increase in mortality risk, even after adjustments were made for diabetes, hypertension and other factors. Research has link short term sleep deprivation, 1 night, to a propensity to load up on larger meal portions and a preference for sugary, salty, high carb foods. Multiple studies have linked chronic sleep deprivation, more than a week, with obesity and early studies have linked lack of sleep to both colorectal and breast cancers! A small, recent study of 15 men and published in the journal SLEEP, found that just one night of sleep deprivation was linked with signs of brain tissue loss!
So let’s be clear on this. Getting less than the recommended 7–9 hours of sleep per night can make you dead a lot quicker!
Let’s get back to the light thing. I know many of you are tapping away at laptops before you go to bed, checking Facebook on your iPhone and watching TV in the bedroom. “We think that the advent of electric lighting has significantly impacted upon sleep-wake patterns, but with the proliferation of electronic devices that emit light we are expecting that these problems will increase,” said Professor Rajasthan, from Monash University’s School of Psychology and Psychiatry.
A recent study in the US showed that devices like laptops, smartphones and tablets emit approximately 30 to 50 lux, about half the illumination of an ordinary room light.
“We know from preliminary reports that this level of light emission, 30 to 50 lux, is sufficient over a week or so to delay the timing of the circadian clock as well as suppress the production of the hormone melatonin,” says Professor Rajaratnam.
Melatonin is produced by the body when it is dark and helps regulate and promote sleep. If you don’t produce enough Melatonin, you can have a hard time falling asleep.
The most disruptive light to the circadian (body) clock, is short wavelength blue light – exactly the same thing your iPad is shining in your eyes.
Clinical psychologist Dr Amanda Gamble, from Sydney’s Woolcock Insomnia Clinic, says she is seeing an increasing number of patients who are presenting with screen-related sleep problems…
“We’ve gone from bigger devices – the computers that were fixed on our desk to the handheld portable devices … so it’s become a much more difficult issue to actually create a boundary between sleep and switching off these devices, because of course they come into the bedroom and a lot of people use their mobile phones as their alarm clock,” she said.
Dr Gamble says there are three main effects resulting from electronic devices.
“Obviously the devices emit light, and they’re often held close to the face, in the case of an iPad for example. The light suppresses melatonin and that makes it harder to fall asleep and delays the sleep pattern,” she said.
“Secondly, these devices are really mentally and physically arousing – they’re interesting, they’re fun and so it takes a while for the brain to wind down and prepare for sleep after using them.”
“The third factor is that often people are using these devices in the bed and this creates a learned association between the bed as being a place of study or work or socializing, rather than keeping the bed just for sleep.”
As already mentioned, there can be long-term health effects for sleep-deprived people,
“They’re at much greater risk of later developing anxiety disorders, depressive illnesses, substance abuse issues and also, on the more physical side, they’re at increased risk of poor blood sugar control, diabetes and so on.” says Dr Gamble.
Poor sleepers experience:
- 7-fold increase in accident risk
- 3 x the absenteeism rate of good sleepers
- Significantly lower job satisfaction
- Slower & poorer career advancement
- Poorer health
- Twice as grumpy
- Less enjoyment of family, friends & social activities
- More difficulty in completing tasks
- Harder to cope with minor irritations
- Twice as stressed
- Less ability to problem-solve, be creative and innovative
Sleep Deprivation – The Risks
- Decreased alertness
- Increased risk of near-miss, incident, accident and fatality
- Decreased physical performance
Stress on an individual and on their family relationships is frequently documented. Shift working is also known to affect an individual’s health in a variety of ways (such areas include):
- Decreased life expectancy
- Increased likelihood of heart attacks
- Increased blood pressure
- Increased chance of diabetes / poorer control in existing condition
- Obesity and weight gain
- Depression and mood disorders
- Gastrointestinal disorders
- Sleep disorders
Stay tuned for Part 2 where I’ll discuss Sleep Hygiene and give you some tips on how to get a good night’s sleep.