A randomized clinical trial by American scientists showed that children who attended a free summer day camp had a significant decrease in body mass index compared to children who did not attend the camp — their body mass index increased over the same observation period. As reported in JAMA Pediatrics, the study was conducted among children from poor and low-income families.
Epidemiological studies show that the peak period for childhood overweight and obesity is during the summer holidays. Moreover, youth from marginalized groups (e.g., from economically or socially disadvantaged families) are at increased risk of unhealthy increases in body mass index during the summer. One hypothesis to explain this pattern is that during the school year, children are exposed to a structured environment (school) that encourages healthy behavior through environmental controls, such as mandatory physical activity and restrictions on high-calorie foods. Systematic reviews show that children do indeed exhibit healthier behavior on school days compared to days without school.
Similar structured features during the summer could include day camps, where children spend 6-8 hours daily, five days a week. These camps provide adequate physical activity and nutrition, which can help children maintain a healthy body mass index.
A research team led by Michael Beets of the University of South Carolina conducted a randomized clinical trial to determine how attending an urban day camp affected the body mass index of children from poor and low-income families. Children in the study group received free stays at an urban camp for eight to ten weeks. Classes began at 7:00 a.m. and ended at 5:00 p.m., with three to four hours of physical activity per day and the remaining time devoted to excursions and intellectual pursuits. The children's diet consisted of breakfast, lunch, and an afternoon snack.
A total of 260 children were randomly assigned to receive a free day camp voucher, while 248 children spent their summer as usual. The researchers found no significant demographic differences between the groups. Data analysis showed that children in the control group increased their standardized BMI z-scores by an average of 0.046 during the summer. Children who spent their summer in city camps decreased their BMI z-scores by 0.094. On average, an increase in the number of camp visits by one day per week led to a decrease in children's BMI z-scores by 0.018–0.034.
According to the scientists, the widespread introduction of free summer city camp programs can reduce the prevalence of overweight and obesity among children from poor families. Future studies need to replicate these results in different regions, as well as determine the optimal “dose” of such programs.
We previously reported that the habit of playing outdoors at 2.5 years old was associated with a reduced risk of developing obesity at age seven.
