Child obesity

Citation

(2009), "Child obesity", Nutrition & Food Science, Vol. 39 No. 4. https://doi.org/10.1108/nfs.2009.01739dab.002

Child obesity

Article Type: Food facts From: Nutrition & Food Science, Volume 39, Issue 4

This cluster focuses on two reviews of interventions for child obesity published in The Cochrane Library (see www.thecochranelibrary.com), 2009, Issue 1, and highlights some of the key health care conclusions and their implications for practice.

Reviews highlighted

• •

  Child and adolescent obesity: family-based programs. Family-based lifestyle interventions that not only modify diet and physical activity but also include behaviour therapy programs can help obese children lose weight and maintain that loss for at least six months. This Cochrane Review also found that in adolescents the effect lasts for at least 12 months. Adding weight controlling drugs orlistat or sibutramine to behaviour change programs for adolescents may provide additional benefits.

• •

  School-based physical activity: has benefits even if it doesn’t help lose weight. School-based health and exercise programs have positive outcomes despite having little effect on children’s weight or the amount of exercise they do outside of school, say Cochrane Researchers who carried out a systematic review of studies on physical activity programs in schools.

Child and adolescent obesity: family-based programs including behaviour therapy can work

Family-based lifestyle interventions that not only modify diet and physical activity but also include behaviour therapy programs can help obese children lose weight and maintain that loss for at least six months. This Cochrane Review also found that in adolescents the effect lasts for at least 12 months. Adding weight controlling drugs orlistat or sibutramine to behaviour change programs for adolescents may provide additional benefits.

These findings mark a change in opinion. A systematic review performed in 2003 could not find enough data to draw any conclusions about the effects of different programs. This time the researchers identified 64 randomised controlled trials involving 5230 participants, enabling them to see some definite effects.

“It is now clear that family-based, lifestyle interventions that include a behavioural program aimed at changing diet and physical activity provide significant and clinically meaningful decreases in overweight and obesity in both children and adolescents compared with standard care or self help regimes”, says lead researcher Hiltje Oude Luttikhuis, who works at Beatrix Children’s Hospital and the Department of Epidemiology in Groningen, The Netherlands.

The worldwide obesity epidemic in young people is continuing to gain pace. The International Obesity Taskforce now claims that, worldwide, 10 per cent of 5-17 year olds are overweight and 2-3 per cent are obese. Paediatric obesity rates now stand at 30 per cent for the Americas and 20 per cent for Europe. Socio-economically disadvantaged children in developed countries and children of higher socio-economic status in developing countries are more likely to be overweight. “This highlights the importance of effective treatment strategies for children and young people already affected by the problem of obesity”, states Oude Luttikhuis’s collaborator, Professor Louise Baur, a paediatrician at The Children’s Hospital at Westmead, and the University of Sydney.

There are many questions left unanswered. “We need to find out what types or aspects of different interventions work better for different groups of children, depending on their age, gender, socioeconomic background, faith or ethnic groups. The importance of self-esteem in influencing how successful an intervention will be, and whether there are any characteristics of individual families or patients that could help identify success, require further effort by researchers”, says Oude Luttikhuis.

School-based physical activity: has benefits even if it does not help lose weight

School-based health and exercise programs have positive outcomes despite having little effect on children’s weight or the amount of exercise they do outside of school, say Cochrane Researchers who carried out a systematic review of studies on physical activity programs in schools.

The research shows that school-based programs increased the time children spent exercising and reduced the time spent watching television. Programs also reduced blood cholesterol levels and improved fitness – as measured by lung capacity. However, programs made little impact on weight, blood pressure or leisure time activities.

Physical inactivity is a key factor behind 1.9 million deaths every year and almost a quarter of all cases of coronary heart disease. People who are overweight as children are more likely to develop heart disease as adults. Exercise helps to maintain a healthy weight, yet studies show most children do not do enough exercise to give any health benefit. The World Health Organisation has identified schools as important settings for promotion of physical activity among children.

The researchers reviewed data from 26 studies of physical activity promotion programs in schools in Australia, South America, Europe and North America. Most studies tried to encourage children to exercise by explaining the health benefits and changing the school curriculum to include more physical activity for children during school hours. Programs included teacher training, educational materials and providing access to fitness equipment.

“Given that there are at least some beneficial effects, we would recommend that schools continue their health promotion programs. These activities should also be supported by public health unit staff, and parents and teachers as positive role models”, says lead researcher Maureen Dobbins, who works at the School of Nursing at McMaster University in Ontario, Canada.

Dobbins believes that schools should make spaces in their timetables to create environments that encourage pupils to engage in physical activity each day as well as having an ethos that encourages increased duration of moderate to vigorous activity each week. “Schools have great opportunities to help pupils learn how to promote health and minimise the risk of acquiring a chronic disease. Providing a healthy structure to their day should enable them to develop healthier lifestyles that may track in adulthood”, she says.

She also suggests an explanation for why some programs often do not improve physical health measures such as weight and blood pressure. “Physical activity classes may be too closely associated with school work, so for some students this makes them feel like they are being made to do more work. Perhaps the key is to promote physical activity by getting children and adolescents to ‘play’ in ways that promote better fitness levels, while at the same time represent fun and adventurous activities”, says Dobbins.

About the Cochrane Library

The Cochrane Library contains high quality health care information, including Systematic Reviews from The Cochrane Collaboration. These reviews bring together research on the effects of health care and are considered the gold standard for determining the relative effectiveness of different interventions. The Cochrane Collaboration (see www.cochrane.org) is a UK registered international charity and the world’s leading producer of systematic Reviews. It has been demonstrated that Cochrane Systematic Reviews are of comparable or better quality and are updated more often than the Reviews published in print journals. The Cochrane Library can be accessed at www.thecochranelibrary.com