Obese Children at Higher Risk for Clogged Arteries

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Woo KS, Chook P, Yu CW, et al.: Effects of diet and exercise on obesity-related vascular dysfunction in children. Circulation 109:1981-1986, 2004.

What is the problem and what is known about it so far?

The number of obese people is increasing. This is especially troubling in children because it could cause early clogging of the arteries (which decreases blood flow to the body).

Why did the researchers do this particular study?

The goal of this study was to see if the risk for decreased blood flow could be lowered in obese children.

Who was studied?

A total of 82 overweight or obese children between ages 9 and 12 were studied.

How was the study done?

Each child had a physical exam where researchers measured their weight, height, and fat content. Levels of fat in the blood were also measured.

Half of the children were put into a group and received diet advice only; the other group received diet help and a supervised exercise program.

After 6 weeks, about half of those in the diet and exercise group changed to diet only. The rest of their group continued with diet and exercise. The diet-only group did not make any changes. A physical exam and blood work were done again after 1 year on the program.

What did the researchers find?

The study showed that the risk of clogging lowered at the 6-week mark in both groups, as measured by lower levels of fat in the blood.

Children who continued the exercise program for a year showed even more improvement.

The group of children who continued the diet but stopped exercising had their blood fat levels return to what they were before the study. This means their risk for clogged arteries went back to the higher, original level.

What were the limitations of the study?

Some children may have exercised harder than other children, which might affect the study results. Also, because children go through hormonal changes as they age, some results may have been affected.

What are the implications of the study?

Diet -- especially when combined with exercise -- improves early signs of clogging of the arteries and blood flow. Having overweight and obese children begin a diet and exercise program could be an important way to improve their health in both the short and long term.