Decreasing the amount of daily sugar consumption can help improve the health of kids with obesity, and the positive effect can be seen after just a few days, according to a new study.
To find out how sugar impacts the health of kids, researchers from the University of California, San Francisco, and Touro University California took 43 obese kids aged 8 to 18 who each had a chronic metabolic problem, like high blood pressure, and reduced the amount of added sugar in their diet for nine days.
In order to rule out the effect of weight loss on their metabolic health, the researchers employed "isocaloric substitution of starch for sugar" — meaning sugar was replaced with starchy food with the same amount of calories — so the kids would not lose weight.
The study's participants ate most of the same foods they usually eat at home, including common favorites like pizza and potato chips. However, foods with added sugar, like pastries, were removed. The kids' total sugar intake was reduced from 28 percent to 10 percent.
At the end of the nine days, the researchers were astonished to see that the kids' metabolic health improved in every aspect even as their weight remained the same. The kids' diastolic blood pressure dropped by five points and their fasting blood sugar also dropped by five points. Their insulin levels went down by 50 percent and their blood fat levels also went down.
"In other words, we reversed their metabolic disease in just 10 days, even while eating processed food, by just removing the added sugar and substituting starch, and without changing calories or weight," lead study author Robert Lustig wrote in the Guardian. "Can you imagine how much healthier they would have been if we hadn't given them the starch?"
Lustig said sugar is not harmful because of how it affects weight, but simply because it's sugar.
"This study definitively shows that sugar is metabolically harmful not because of its calories or its effects on weight. Rather, sugar is metabolically harmful because it's sugar," he told HealthDay.
Lustig also said the results of their study dispels the idea that "a calorie is a calorie."
"This study demonstrates that 'a calorie is not a calorie,'" he explained. "Where those calories come from determines where in the body they go. Sugar calories are the worst, because they turn to fat in the liver, driving insulin resistance, and driving risk for diabetes, heart and liver disease."
The study was published online in the Oct. 26 issue of the journal Obesity.
