|
 Researchers measured height and hip size to assess body fat in about
600 children when they were 8 to 10 years old, and again two years
later. They found every 1 percent of additional body fat at the
start of the study was linked to a 3 percent decline in sensitivity
to the hormone insulin, a shift that can allow excess sugar to build
up in the blood and lead to diabetes.
The study published in JAMA Pediatrics also found more exercise and
less screen time were linked to better insulin sensitivity, which
might reduce the risk of diabetes. Reduced body fat might explain at
least part of this connection, said lead study author Dr. Melanie
Henderson of the University of Montreal.
“Our findings suggest that we should be encouraging children early
on to be physically active, and that we should reduce their screen
time, in order to favor a healthy body weight and better
cardiometabolic health later on in life,” Henderson said by email.
Henderson and colleagues focused on what’s known as insulin
sensitivity, the body’s ability to use this hormone to regulate
levels of blood sugar, or glucose, and turn it into fuel for cells.
Type 2 diabetes is associated with obesity and occurs when the body
can’t make or use enough insulin to prevent glucose from
accumulating in the blood.
Researchers assessed children once when they were 9.6 years old on
average, and again two years later. The majority of the kids had not
gone through puberty at the start, and by the end of the study two
thirds had experienced this transition.
All of the children had at least one obese parent, and 23 percent of
the kids were obese themselves at the start of the study. Another 19
percent were overweight.
The children who had more girth around their hips or bigger
increases in hip size during the study were more prone to insulin
insensitivity than kids with slimmer hips. Examining excess
circumference around the hips, a measure known as adiposity, is
thought to be better than relying on overall weight to assess fat
because it can more accurately account for muscle and flab.
Physical activity seemed to be the main explanation for the
differences in childrens’ adiposity. Every 10 minutes per day of
moderate to vigorous physical activity was associated with 3.5
percent lower body fat at the end of the study, even after adjusting
for fitness levels and the amount of screen time. This amount of
exercise was also linked to a 4.8 percent increase in insulin
sensitivity.
[to top of second column] |
At the same time, every one-hour increase in screen time at the
start of the study predicted a 2.9 percent increase in body fat.
This amount of screen time was also associated with a 4.5 percent
reduction in insulin sensitivity.
One shortcoming of the study is that 66 children, or about 10
percent, dropped out before the end, the authors note. The youth who
left the study tended to be more insulin resistant and have more
body fat than the children who stuck with it through the end.
Even so, the findings are important because metabolic health during
childhood can influence whether people later have health problems
including diabetes, hypertension, obesity, sleep apnea, heart
attacks and strokes, said Dr. Kim Eagle, a researcher at the
University of Michigan Frankel Cardiovascular Center in Ann Arbor.
“Daily decisions about activity, screen time, food and beverage
consumption and overall energy balance matter and can influence
profoundly what our children’s future health state will look like,”
Eagle, who wasn’t involved in the study, said by email.
“We live in a toxic culture filled with empty calories, video games,
endless screen time opportunities, and not enough health education,”
Eagle added. “Studies like this one should help us find the will to
take action.”
SOURCE: http://bit.ly/1SeiOIS JAMA Pediatrics, online February 8,
2016.
[© 2016 Thomson Reuters. All rights
reserved.] Copyright 2016 Reuters. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed.
 |
