Clinical Question: Can a specific program of diet and exercise result in sustained weight loss in children?

Setting: Outpatient (primary care)

Study Design: Randomized controlled trial (nonblinded)

Allocation: Uncertain

Synopsis: The researchers conducting this study began with 54 obese children between six and 16 years of age. The children were assigned randomly to a control group that received a single nutrition counseling session or to an active treatment group. Active treatment consisted of heavy-duty dietary and exercise modification for three months. It is not clear whether allocation to treatment groups was concealed, and it is possible that children more likely to respond to treatment were enrolled preferentially.

The dietary intervention consisted of six meetings over a three-month period with parents and the child. These counseling sessions focused on food choices, nutrition information, and change in behavior. The children were placed on a diet of approximately 30 percent fewer calories than the reported intake or 15 percent fewer calories than the estimated daily required intake. The exercise program was conducted two hours per week by physicians who were former members of the Israeli national track and field team and consisted of games focusing on endurance; the children were encouraged to add an extra 30 to 45 minutes of walking or other exercise per week. Analysis was per protocol and not by intention to treat. Because of dropouts early during the intervention period and in the subsequent one-year follow-up, the groups dwindled to 20 patients each.

After three months of diet and exercise intervention, the children in the treatment group lost an average 2.8 kg (6.2 lb), whereas the children in the control group gained an average of 1.1 kg (2.4 lb). Body mass index and body fat percentage also declined in children in the intervention group. Over the one year of follow-up, children in the control group gained an average of 5.2 kg (11.4 lb); the children in the intervention group gained an average of 0.6 kg (1.3 lb;P < .05). Body mass index increased in the control group but decreased in the intervention group. Other significant differences at one year included lower body fat percentage, amount of exercise activity, and endurance time on a treadmill. Both groups reported a decrease in the time spent watching television or playing video games, from an average of 4.5 to 4.8 hours per day to 3.3 to 3.4 hours per day one year later.

Bottom Line: An intensive three-month program of dietary counseling, a hypocaloric diet, and structured exercise can cause weight loss in children that is sustained over one year. More important, the program seemed to increase the amount of exercise the children performed, and this increase was sustained after the intervention was discontinued. (Level of Evidence: 2b)