Green light also alters sleep, television before bed still bad

Sleep experts warn the bright light produced by televisions, computers and iPads can meddle with sleep. There’s a line of products made to counter that effect by blocking out blue light wavelengths, which can reset the body’s circadian clock. Online you can purchase special sunglasses and screen filters, but there’s no guarantee the products will work as advertised and prevent insomnia.

There’s new evidence that its not just blue wavelength light that alters the body’s circadian clock. Researchers at the Brigham and Women’s Hospital in Boston found the green light produced from those same sources has a similar effect.

More than a decade ago, scientists discovered there are special cells in the eye that contain the blue light-absorbing pigment melanopsin. When the eye detects blue light, it delays the body from secreting melatonin.

The authors of the new study wanted to see if the eye’s rods and cones, which respond to green light wavelengths, also contributed to the body’s circadian adjustment.

The researchers exposed a group of volunteers separately to blue and green light, both for several durations and intensities. The experiment happened in the evening, before the body naturally secretes melatonin. Scientists measured the subjects’ melatonin response in each condition.

At low intensity, there was very little difference in the body’s reaction to blue and green light wavelengths. However, blue light produced a greater effect over time and at higher intensities.

The authors suggest there’s room to improve light therapy for sleep disorders based on these findings. The treatment may be more effective if the light devices combined blue and green light.

The study may have potentially substantial implications for the field of sleep research.

AASM President Clete Kushida told USA Today “(the finding) sort of goes against what was believed before.”

He said researchers should explore the possibility that the full spectrum of light may affect the body clock.

For our readers who aren’t scientists, the study reinforces the notion that evening use of electronic screens can hinder sleep, and special sunglasses won’t help. We recommend shutting off the television or other bright electronic devices an hour before bedtime and picking up a book, or better yet, an e-reader.

Fall Back to Sleep & Standard Time

Tonight marks the end of daylight saving time. The return to standard time officially occurs at 2 a.m. Sunday morning.

This means you get an extra hour in your day. This is a great opportunity to catch up on your sleep!

To get an extra hour of sleep, you should go to bed at your normal bedtime. Then set all your clocks back an hour just before getting into bed.

Lifestyle choices, personal obligations and occupational demands can cause you to become sleep deprived. Ongoing sleep disorders or medical conditions can also cause sleep deprivation. When you are constantly getting less sleep than you need, you develop what is known as a ‘sleep debt’.

Sleep deprivation is linked with increased risk for obesity, illness and death. It can also lead to decreased alertness and performance during the day.

According to a study presented at SLEEP 2009, watching television is currently the most influential cue people use to decide when to go to bed.

Authors of the study say that people can reduce their sleep debt by watching less TV at night and going to bed earlier. You can also eliminate your sleep debt by sleeping for longer time periods each night and improving your sleep hygiene.

Sleep experts recommend that adults sleep between seven and eight hours each night.

Learn more about sleep deprivation at Sleep Education.com.

Visit an AASM-accredited sleep disorders center if you have an ongoing sleep problem.

The Young & the Restless: Children, TV & Bedtime

The AP reports that there is some controversy over a bedtime TV program for children. “The Good Night Show” is a three-hour block of programs for children between the ages of 2 and 5. It airs from 6 p.m. to 9 p.m. on the PBS Kids Sprout network.

A network executive says the show is a helpful tool in the “real world” where most homes have a TV on at night. It’s a better viewing option for children than other programs that are on at the same time.

But critics say that parents should be interacting with their children instead of plopping them in front of the TV at night. They also say that TV viewing can make it harder for children to fall asleep. It stimulates them when they should be winding down.

Research shows that there is good reason to be concerned. Studies indicate that watching TV can have a negative effect on children’s sleep.

A study in 1999 involved 495 children in kindergarten through the fourth grade. Increased TV viewing at bedtime was linked to bedtime resistance, delayed sleep onset, sleep anxiety and short sleep duration.

Research also shows that sleep problems frequently occur when children have a TV in their bedroom.

A 2007 study involved children who were 5.5 years of age. Having a TV in the bedroom was associated with sleep problems. Forty-one percent of the children had a TV in their bedroom.

You might think that this problem is unique to children in the U.S. But it is common in other countries as well.

One study involved children between 6 and 12 years of age in Japan. Watching TV, playing video games and surfing the Internet had a negative impact on sleep. Children were more active before bedtime if they had a TV or video game system in their bedroom.

About 18 percent of children in a Chinese study had a TV or computer in the bedroom. These children had later bedtimes and wake times, and shorter sleep durations. They also were more likely to display bedtime resistance and sleep anxiety.

In a study from Belgium, teens with a TV set in their bedroom went to bed later and spent less time in bed. Teens who watched more TV also woke up later and were more tired.

It’s clear that parents should keep the TV out of their child’s bedroom. While you’re at it, take the computer out of the bedroom too.

You also can help your child wind down for bedtime by turning off the TV and the computer earlier in the evening.