How effective are interventions in preventing childhood obesity?
There was strong evidence to support beneficial effects of child
obesity prevention programmes on body mass index (BMI). The
best estimate of effect on BMI was of a 0.15kg/m2 reduction,
which would correspond to a small but clinically important shift in
population BMI if sustained over several years. The interventions
were predominantly based on behavioural change theories and
implemented in education settings. Analysis by age group (0–18)
indicated the strongest evidence of effectiveness was in 6 to 12
year olds, with promising findings also in 0–5 year olds, particularly
for interventions conducted in home or healthcare settings.
Only 8 studies reported on adverse effects, and no evidence of
adverse outcomes, such as unhealthy dieting practices, increased
prevalence of underweight or body image sensitivities, was found.
Interventions did not appear to increase health inequalities,
although this was examined in fewer studies.
The unexplained heterogeneity of effects observed, potential
attrition bias in many studies, and the likelihood of a small-study
bias may have inflated the estimate of effect, so these findings
should be interpreted with caution.
Prevention of childhood obesity is an international public health
priority given the significant impact of obesity on acute and
chronic diseases, general health, development and well-being.
The international evidence base for strategies that governments,
communities and families can implement to prevent obesity and
promote health is accumulating but remains unclear.