Field Notes
Childhood Sedentariness Causes Excessive Insulin, Raising Risk of Type 2 Diabetes
An increase in sedentary time from childhood is associated with a significant increase in blood insulin concentration, a new study shows. However, light physical activity (LPA) could reduce the risk of excess insulin and insulin resistance. The study was conducted in collaboration between the Universities of Bristol and Exeter and the University of Eastern Finland, and the results were published in the Journal of Clinical Endocrinology and Metabolism.
Based on the University of Bristol’s Children of the ’90s data, the study included 792 children followed up from 11 to 24 years of age. At baseline, they spent an average of six hours per day in sedentary activities, which increased to nine hours per day during the follow-up.
This increase in sedentary time was associated with continuously higher insulin levels in fasting blood, especially among youths with overweight and obesity, whose risk of excess insulin increased by 20%. On the contrary, an average of three to four hours of LPA per day throughout the follow-up decreased the risk of excess insulin by 20%. Higher LPA was also associated with lower insulin resistance.
Participating in moderate-to-vigorous physical activity (MVPA) showed signs of reducing insulin but to a much smaller extent.
Earlier results from the same cohort have linked sedentariness to obesity, dyslipidemia, inflammation, and premature vascular damage. The researchers have also observed a vicious cycle of obesity and worsening insulin resistance.
LPA is now emerging as an effective approach to reversing the deleterious effect of childhood sedentariness. However, whether long-term exposure to LPA from childhood reduces excess glucose, insulin, and insulin resistance hasn’t been examined before. This is because only a few studies have repeatedly measured all these in a large population of healthy youth.
The current study is the largest and the longest follow-up accelerometer-measured movement behavior and glucose, insulin, and insulin resistance study in the world. The participants wore accelerometer devices on their waists at ages 11, 15, and 24 years for four to seven days and had fasting glucose and insulin measurements at ages 15, 17, and 24 years. Their fasting blood samples were also repeatedly measured for HDL cholesterol, LDL cholesterol, triglycerides, and high-sensitivity C-reactive protein. Blood pressure, heart rate, smoking status, socio-economic status, and family history of CVD were controlled for in the analyses.
“Calling a spade a spade, our recent studies have identified childhood sedentariness as a monster that threatens the young population across the globe, no thanks to excessive screen use,” says Andrew Agbaje, MD, MPH, PhD, FESC, FAHA, an award-winning physician and associate professor (docent) of clinical epidemiology and child health at the University of Eastern Finland.
“Sedentariness should be recognized as one of the 21st century independent causes of excess insulin, fat obesity, high lipid levels, inflammation, and arterial stiffness. Three to four hours of LPA per day is critically important to antagonizing childhood sedentariness. While we await the update of the current World Health Organization’s physical activity guideline, which doesn’t include an LPA recommendation, public health experts, health policymakers, health journalists, pediatricians, and parents should encourage kids to participate in LPA daily.”
— Source: University of Eastern Finland
Childcare Pick-Up: A One-Hour Window to Build Healthier Eating Habits
Millions of working parents know the routine: bustle the kids off to childcare in the morning, work all day, and then fight the daily traffic jams to get the kids back home. Something to drink and maybe a snack to munch can help ease the commute.
Understandably, few parents take the time to think about the nutrients or calories involved, but experts at Cincinnati Children’s decided to take a closer look. Their eyebrow-raising findings were published in the Journal Children’s Health Care.
The researchers took a fresh look at older data contained in daily food journals kept by more than 300 families of children who attended 30 childcare centers that participated in the Preschool Eating and Activity Study (2009–2011). They found that the hour after parents and caregivers picked up their children stood out as a high-calorie, relatively less healthful part of the child’s overall diet.
Overall, these children, aged 3 to 5, consumed more than 1,471 kcal across the entire day—an amount that’s on the high end of recommended daily limits. Of that amount, 290 kcal, on average, were consumed in the hour after leaving daycare. That’s about 20% of the day’s entire calorie intake.
Adding concern: after-care food and drink accounted for about 22% of the day’s added sugar and about one-third of the sweet and salty snack foods the children ate.
“Every parent knows how busy that time of day can feel. Parents can feel stressed, the kids may be cranky, hungry, or tired. There’s nothing wrong with treats once in a while,” says senior author Kristen Copeland, MD, of the Division of General and Community Pediatrics. “But that car ride home also can be an opportunity to instill more healthful habits instead of less healthful ones.”
If busy parents want to try a small change that might make a big difference, consider stocking the car with veggie sticks, cheese, fruit slices, and low-sugar drinks such as water or milk. A few minutes of preparation can make it easier to skip the high-calorie drive-throughs and sugar-loaded packaged snacks.
“Children of preschool age are in a highly habit-forming time of their lives. They thrive on routine,” Copeland says. “Children often look forward to the car ride home, which makes that time an opportunity to start a healthful snacking habit that could last a lifetime.”
— Source: Cincinnati Children’s Hospital Medical Center