By Dr. Mercola
Putting a television in your child's bedroom may seem like a special treat, but it's one that could be setting them up for a lifetime of poor sleep habits, and by association, obesity.
And it's not only TVs that are to blame. Computers, video games, cell phones and other electronic gadgets are just as bad, and new research shows that if they're in your kids' rooms, it's time to get them out.
Electronic Gadgets in Kids' Rooms Promote Obesity and Unhealthy Lifestyles
In a survey of more than 3,000 fifth graders,1 half of the children said they had either a television, DVD player, or video game in their rooms, 21 percent said they had a computer and 17 percent said they had cellphones (and 5 percent of the kids said they had all three!).
If you think this doesn't impact your child's sleep habits … think again. More than half (57 percent) said they would use these devices even after they were supposed to be asleep, for instance staying up later to watch TV in bed. As you might suspect, those who had access to electronic devices generally slept less, and shorter sleep duration is linked to obesity.
Lost Sleep Contributes to Obesity
Getting just one extra hour of sleep a night was linked to a 28 percent lower risk of being overweight and a 30 percent lower risk of being obese, according to the study. On the other hand, kids who used electronic devices at bedtime were nearly 1.5 times more likely to be overweight. Among those who had three or more such devices in their bedroom (such as a TV, computer and video games), the risk jumped to over 2.5 times.
Part of the problem is that the kids are staying up later than they should to watch TV or play video games, and this means they're sacrificing valuable sleep time. Your circadian rhythm has evolved over hundreds of generations to align your physiology with your environment. Your body clock is "set" to sleep at night and stay awake during daylight hours. If you are deprived of sleep, conflicting signals get sent to your body.
Too little sleep impacts your levels of thyroid and stress hormones, which in turn can affect your memory, immune system, heart and metabolism, and much more. Over time, lack of sleep can lead to:
- High blood sugar levels and an increased risk of diabetes -- Sleep-deprived people tend to eat more sweet and starchy foods rather than vegetables and dairy products. Researchers suspect these cravings stem from the fact that your brain is fueled by glucose (blood sugar); therefore, when lack of sleep occurs, your brain searches for carbohydrates. In short, sleep deprivation puts your body into a pre-diabetic state, and makes you feel hungry, even if you've already eaten.
- Weight gain -- When you are sleep deprived, your body decreases production of leptin, the hormone that tells your brain there is no need for more food. At the same time it increases levels of ghrelin, a hormone that triggers hunger.
- Accelerated aging
(high blood pressure) and depression
- Increased risk of cancer by altering the balance of hormones in your body, such as reducing the production of melatonin
TV also appears to be linked to health risks regardless of its impact on sleep, through other mechanisms, such as reducing physical activity. One study found, for instance, that the more hours spent in front of a television in early childhood, the more a child's muscular fitness decreased and the larger their waistlines became as pre-teens.2
TV Watching Linked to 15 Health Risks in Kids
Much of the TV debate focuses on advertising messages and violent or sexually explicit programming, and their impacts on young minds. And while these certainly can be damaging, it turns out that TV may be harmful no matter what your kids are watching.
Dr. Aric Sigman, a British psychologist, analyzed 35 different scientific studies on television and its effect on the viewer.3 He found the damage comes not from the TV programs themselves, but from the vast amount of time kids are spending watching television and computer screens. This activity produces an almost narcotic effect on your brain, actually numbing areas that would be stimulated by other activities, like reading.
Dr. Sigman has identified 15 negative effects that he believes can be blamed on watching television, stating:4
"Watching television, irrespective of the content, is increasingly associated with unfavorable biological and cognitive changes. These alterations occur at viewing levels far below the population norm. Given the population's sheer exposure time to this environmental factor it is more than puzzling to consider how little awareness and action has resulted."
The risks Dr. Sigman revealed include:
Decreased attention span
Limited brain growth
Even the Light from TVs and Other Glowing Gadgets Interferes With Your Child's Sleep … and Health
Computer screens, televisions and most light bulbs emit blue light, to which your eyes are particularly sensitive because it's the type of light most common outdoors during daytime hours. As a result, they can fool your brain into thinking it's still daytime when it's actually night, which disrupts your sleep patterns.
A study done with hamsters at Ohio State University Medical Center found that chronic exposure to dim light at night can cause signs of depression after just a few weeks.5 The study also showed changes in the hamsters' hippocampus similar to brain changes seen in depressed people. They pointed out that rates of depression have risen along with exposure to artificial light at night.
The link could be due to the production of the hormone melatonin, which is interrupted when you're exposed to light at night. There are many studies that suggest melatonin levels (and by proxy light exposures) control mood-related symptoms, such as those associated with depression -- especially winter depression (aka, seasonal affective disorder, or SAD).
Exposure to light during the night can seriously impact your body's internal clock, even leading to metabolic changes and weight gain. In fact, mice that were exposed to dim light during the night gained 50 percent more weight over an eight-week period than mice kept in complete darkness at night.6 They also had increased levels of glucose intolerance, a marker for pre-diabetes.
The weight gain occurred even though the mice were fed the same amount of food and had similar activity levels, and the researchers believe the findings may hold true for humans as well. So this is another issue to be aware of if your child has access to any type of glowing gadget at night.
The Solution is Simple…
Get the TV, computer, video games and cell phone out of your child's bedroom, and limit their screen time during the day. Your child may protest, but this is a simple change that can help protect, and even improve, their health.
It's a no-brainer that if your child has a TV in their room, they're going to spend more time watching it, but one study really made that point clear, showing that having a TV in the bedroom increased viewing time by nearly nine hours a week.7
According to Dr. Sigman and other experts, children under age 3 should watch no TV at all, while those 3-7 should watch no more than 1.5 hours a day. For older kids, two hours of TV and/or computer/video game use should be the daily limit. In addition, once it's bedtime, keep all light off at night (even if you get up to go to the bathroom) -- and this includes your computer and TV.