Regardless of fat levels, a child's overall health status can be influenced by other factors such as physical activity, according to a recent study.

Researchers from the University of Alberta and Alberta Health Services found that one-third of kids with obesity are metabolically healthy, suggesting that physical activity and diet trumps the digits on a scale, according to a press release.

"It's not all about fat, even for kids who meet the definition of obesity," Geoff Ball, senior author and associate professor of pediatrics in the University's Faculty of Medicine & Dentistry, said in a statement. "Lifestyle behaviors - how physically active they are and what they eat - those things have an effect on their health, independent of fatness."

For the study, researchers studied five years' worth of clinical data, tracking the age and body composition of obese children and lifestyle behaviors.  They also studied clinical indicators associated with obesity such as insulin resistance, blood pressure, and fat and glucose levels in the blood.

The found that children with high fat levels who were more physically active, metabolically healthier children were shorter, lighter and less overweight than their metabolically unhealthy peers. This group also spent less time sitting in front of a television screen, computer or video game console and ate fewer overall calories, including less fat and fewer servings of meat.

Ball said traditional measures of obesity, such as body mass index (BMI), does not tell the whole story.

"Obesity is often described as a complex disease with lots of causes and lots of consequences. Not everyone has the same consequences," he said. "Someone with Type 2 diabetes could have less body fat than somebody who has quite a bit more body fat and doesn't have Type 2 diabetes. There is considerable variability between individuals."

Researchers said their findings, published in Diabetes Care, should help physicians and other health professional understand the complexity of obesity for treating patients and prioritizing referral to specialized weight-management care.