Obese kids as young as 8 years old already have dangerous damage to their hearts, researchers reported on Tuesday.
Imaging scans of their hearts show a thickening of the muscle — a sign of strain that can lead to stroke, abnormal heart rhythm, heart failure and sudden death.
Linyuan Jing of the Geisinger Health System in Danville, Pennsylvania, and colleagues compared 20 obese kids to 20 normal-weight kids, conducting a heart imaging scan called cardiac magnetic resonance.
"Obese children had 27 percent more muscle mass in the left ventricle of their hearts and 12 percent thicker heart muscles - both signs of heart disease - compared to normal weight children," Geisinger said in a statement.
"This evidence of cardiac remodeling was present in obese children as young as age 8," Jing and colleagues wrote in a summary of their findings, presented to a meeting of the American Heart Association.
"This implies that obese children even younger than 8 years old likely have signs of heart disease too," Jing said.
"Ultimately we hope that the effects we see in the hearts of these children are reversible; however, it is possible that there could be permanent damage. This should be further motivation for parents to help children lead a healthy lifestyle," Jing added.
One in three children are either overweight or clinically obese, putting them at a greater risk for diabetes, high cholesterol, and high blood pressure. Poor diet and a lack of exercise are both to blame, experts say.
Obesity in kids is not measured the same way as in adults. Children are considered overweight if they are in the 85th to 95th percentile of body mass index, or BMI, for all children their age. That means they weigh more than 95 percent of kids their age and height. Anything over the 95th percentile is obese.
Data from very large national surveys show that all types of obesity are on the rise in American children.
Jing's team didn't include children with diabetes or who were too large to fit into the magnetic resonance scanner.
"As a result, this means the actual burden of heart disease in obese children may have been under-estimated in our study because the largest kids who may have been the most severely affected could not be enrolled," Jing said.
Recent studies show there are things that parents and doctors can do. One found that cutting sugar for just a few days helped kids cholesterol and blood sugar levels look better.
And another found that weight loss surgery can be effective and have long-term benefits.