As if parents don’t already have enough to worry about, a recent scientific study has found that light exposure contributes to an increased BMI (body mass index) in young children. Your BMI is a number that measure the amount of body fat you are carrying, in relation to your height and weight. The bigger the number, the worse off you are. In essence, exposure to light is potentially making our kids fat!
The study measured how much artificial light preschoolers were exposed to, while it was dark outside (between sunset and sunrise). For the study, the following items were considered sources of light: regular household lighting, night lights (OMG, what?!) and electronic equipment including, televisions, cell phones, tablets and computers. It may sound crazy, but the findings indicate that for each hour of artificial light exposure, a preschooler’s BMI will rise by .6 units. Although it may not seem like a dramatic increase, the researchers remind us that BMI trends within the first 5 years of life predict BMI in adulthood. Yikes!
The study found that the total amount of light exposure was more critical than the timing. For example, an hour of light exposure beginning at 8 pm had the same effect as an hour of light exposure beginning at 2 am. The researchers also note that previous studies have associated sleeplessness with increased BMI. This supports the findings in this light study, because the less you sleep, the longer you are exposed to light.
The researchers offer a couple explanations for these findings:
- Children may have an increased sensitivity to light, when compared to adults. (They identified this as an area that would benefit from further research.)
- Extra light exposure may screw with the body’s natural biological settings. The body is designed to function during the day and rest at night. Unfortunately, ever since society abandoned butter churning and plowing fields by horse, we have also stopped using the sun as a clock. Without the appropriate amount of downtime, a metabolism simply cannot function properly.
Should you be concerned?
Yes and no. The researchers note that not all children in the study were considered overweight or obese. Ultimately, as light exposure increased, BMI increased. But, many of the children in the study were still within a healthy weight range. Also, the sample size for the study was relatively small. They only used 48 children.
The bottom line is, in my opinion, the relationship between light exposure and BMI should definitely be researched further, before you limit your child’s after-dark activities to reading by candle light.
What’s your take on it? Will these findings change your evening routine?