When I first began looking into the research behind screens and the stress response a few years ago, there was one major study linking screen-time to metabolic syndrome (defined below) in adolescents. Now, just a short time later, the evidence has become quite robust.
Public health researchers the world over are implicating screen-time as a risk factor for metabolic syndrome in adolescents; Korea National Health and Nutrition Survey: Kang et al, 2010; Australia: Hardy et al, 2010; Norway: Danielson et al 2011; European Youth Heart Study: Grontved et al 2012; Canada/US: Mark & Janssen, 2008. Interestingly, the risk seems to hold regardless of physical activity level. In other words, if we look at two children with the same activity/exercise levels, but Child A’s sedentary activity is reading, while Child B’s sedentary activity is screen-related, Child B will have a higher risk of developing metabolic syndrome. Evidence suggests that screen-related activities cause stress, inflammation, and changes in blood sugar regulation, all of which contribute to risk for metabolic syndrome. Television in particular seems to increase the risk, possibly by slowing down metabolic rate.
So what is metabolic syndrome? Also known as "Syndrome X," metabolic syndrome is a combination of conditions related to blood pressure, lipids, blood sugar regulation and obesity, that leads to increased risk of diabetes and heart disease when they occur together. The specific criteria varies according to different organizations, and most studies use adult criteria or adapt them slightly for children and teens.
Here is the International Diabetes Foundation’s criteria for metabolic syndrome in adults:
*High waist circumference (> 37” in men and >32” in women; for teens this may be based on percentiles, e.g. > 90th percentile), plus two or more of the following:
*Raised blood pressure (>130/85, of either the systolic (top) or diastolic (bottom) number)
*Low HDL (<40 in men and <50 in women; this is the “good” cholesterol)
*High triglycerides (>130), and high fasting blood sugar (fasting glucose>100)
Note: In children and teens, it may be most important to simply look at waist circumference percentile.
So what to do? According to the International Diabetes Foundation, “Diabetes and cardiovascular disease cause death and disability…this is the first generation where children may die before their parents.” This is alarming, but the good news is that metabolic syndrome is completely reversible with lifestyle changes. Thus far interventions have focused on diet and increasing physical activity levels, which are of course imperative. But these studies suggest we need to turn our focus toward another avenue of treatment—that of dramatically reducing or even eliminating screen-time—to cut down risk.
And here’s another reason to take heed: seeing this as an opportunity, there’s a push by the pharmaceutical industry to start using cholesterol-lowering drugs in children. From a mental health perspective, this is a dangerous road to go down. Cholesterol is the precursor of most of our hormones, and is a structural component in brain cell (and other cell) membranes, serving to keep the membrane fluid, flexible, and permeable. Cholesterol is also necessary for vitamin D production, which in turn is essential for mood and cognition. When cholesterol becomes depleted from long-term use of cholesterol-lowering drugs, mental health suffers. Additionally, these drugs deplete CoQ 10 (which is necessary for all energy-requiring processes in the body), and frequently cause muscle pain, mobility issues, and falls. What happens when these drugs are used in children, whose brains and bodies are still developing? No one really knows yet. Using these drugs in children will be nothing short of an experiment.
There are many reasons to look at these metabolic syndrome trends very seriously and to take action where we can. Cutting down on refined sugar and fast foods, eating more fruits and veggies, and increasing exercise appear to be only part of the equation. We must begin to restrict screen-time (or even eliminate depending on the risk involved) much more severely than we are doing now. Whether it be food choices or activity choices for your child or teen, align with nature as much as possible and you’ll be on the right track.
 This is in contrast to other effects of screen-time I’ve discussed in previous posts, in which interactive screen time seems to cause more emotional dysregulation and executive dysfunction than television viewing. Different screen-time “profiles” may cause different sets of risk factors.