Child Exposure to Light tied to Body Mass, Weight, Study Says
Exposure to light can affect children's body mass, a new study is reporting.
For this research conducted at Queensland University of Technology, the team recruited child participants between the ages of three and five from six childcare centers located in Brisbane. They tracked the children's sleeping patterns, activity and exposure to light for two weeks, and recorded their height and weight. The team then conducted a follow up test 12-months later.
For light exposure, the researchers factored in both natural outdoor light and artificial indoor light. The team referred to the two-weeks of monitoring as "time 1."
The team found that at time 1, children who were exposed to a moderate-intensity level of light earlier in the day had higher body mass index (BMI), which was calculated using height and weight. Children whose exposure levels were greatest during the afternoon tended to have lower BMIs.
During the 12-month follow up, children who had the highest overall levels of exposure were more likely to have higher BMIs. This correlation remained significant even after the researchers accounted for the information they collected at time 1.
"Around 42 million children around the globe under the age of five are classified as overweight or obese so this is a significant breakthrough and a world-first," PhD student and research Cassandra Pattinson said reported by Medical Xpress. "Artificial lighting, including light given off by tablets, mobile phones, night lights, and television, means modern children are exposed to more environmental light than any previous generation. This increase in light exposure has paralleled global increases in obesity."
Although the team did not find a cause-and-effect relationship, they explained that the link between light exposure and weight was probably tied to how light can influence the body's circadian clock.
"The circadian clock - also known as the internal body clock - is largely driven by our exposure to light and the timing of when that happens. It impacts on sleep patterns, weight gain or loss, hormonal changes and our mood," Pattinson said "Factors that impact on obesity include calorie intake, decreased physical activity, short sleep duration, and variable sleep timing. Now light can be added to the mix."
The researchers noted that since more children are being exposed to light today due to technological devices, ranging from smartphones to iPads, it could be beneficial to find out how light can be used to help children lose weight or maintain a healthy one.
The study was published in the journal, PLOS ONE.