For most children getting a good amount of sunlight and sleep go hand in hand. A great day for a typical child is running around on a sunny day, scarfing down whatever junk food he or she can get their hands on and then heading home for some rest.
But kids who stay inside all day and don't get enough sleep at night could face problems like obesity, lacking focus at school and low energy.
And for children living with attention deficit hyperactivity disorder (ADHD), not getting enough sunlight and sleep could be making their condition even worse.
For years, researchers have been studying the internal factors that lead to children who have ADHD, but now a group of researchers are looking at external factors, known as "The 3 S's" -- sunlight, sleep and screens.
Eugene Arnold, MD, a psychiatrist and ADHD expert at The Ohio State University Wexner Medical Center's Nisonger Center said looking at external factors allowed him to learn new things about children with ADHD.
"This opens up new vistas for us, new things to be investigated that maybe we hadn't quite thought about before," he said.
It's not only a lack of sun and sleep that could be harming children with ADHD, the amount of TV and computer time they get could be worsening their condition too.
More sun, less ADHD
Interestingly, places that have more sunlight have fewer cases of ADHD, researchers found. Places like Arizona, Colorado, California, Spain and Mexico, are all considered "sunny" regions because of the high solar intensity in these areas, and all of these places have a fewer ADHD patients.
And places that have less sunlight have more cases of ADHD, researchers say.
"It's about a 2-to-1 ratio. There are many possible explanations. For example, with more sunlight maybe kids get out more to play and get more of the exercise that, increasingly, we know is good for brain function," Arnold said.
According to recent statistics from the Centers for Disease Control and Prevention (CDC), around 6.4 million children have received an ADHD diagnosis in their lifetime, which is a 16% increase since 2007 and a 53% increase in the last 10 years.
Over-diagnosed
However, many believe that children are being diagnosed too quickly with the mental disorder, and that some parents are eager to give their children medication as a fast cure for hyperactivity.
"There's no way that one in five high school boys has ADHD," said James Swanson, professor of psychiatry at Florida International University, in an interview with the New York Times.
"If we start treating children who do not have this disorder with stimulants, a certain percentage are going to have problems that are predictable -- some of them are going to end up with abuse and dependence. And with all those pills around, how much of that actually goes to friends? Some studies have said it's about 30 percent," Swanson said.
Tim Sutton, the Commissioner of Alamance County in North Carolina agrees and says there seems to be a desire to nudge parents into believing their child has ADHD.
"I am concerned about our children," he said in an interview with a local news outlet. "They are claiming that there are thousands of kids in this county who have got attention deficit disorder and I'm not saying we don't have some but the ratio I think probably is higher than it would be because I think there is too much of an effort to push families and children into it."
More drugs
And more kids being diagnosed with ADHD, obviously means more kids are being prescribed powerful drugs like Ritalin and Adderall.
Out of the 6.4 million children who were diagnosed with the mental disorder, two-thirds were prescribed those or similar drugs, statistics show. According to researchers at the U.S. National Institute of Mental Health, children aged 6 to 12 were prescribed ADHD drugs the most.
And some people question how effective ADHD drugs are -- specifically Ritalin -- when taken over long periods of time.
In a study published in the medical journal PLOS ONE, researchers found that long-term use of Ritalin could lower the efficacy of the drug and when patients stop taking it, their symptoms could get worse.
Of course future studies will be done on ADHD, Ritalin and children, as the mental disorder has been quite the hot topic among researchers and parents for quite some time.
But until then, researchers at Wexner Medical Center believe that external factors like TV and computer use have to be considered if we want to know more about children and ADHD.
"There's a correlation with things like irritability, impulsiveness, inattentiveness -- which are core symptoms of ADHD," said Arnold. "And what's robbing them of sleep may be their computer and TV screens. They emit a blue light that could be disrupting melatonin, which is the hormone that helps regulate sleep. Children's duration of sleep has decreased over the past decade or two, since the introduction of those electronic devices."