Taffy Makaya, Rebecca Poole and Kavitha Rozario
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INTRODUCTION
Childhood obesity represents an evolving pandemic, with 30% of English
children noted to be overweight or obese. This is comparable to rates in
America where 32% of children are classed as obese or overweight [1, 2].
Globally, an estimated 43 million preschool children (aged less than 5) were
overweight or obese in 2010, representing a 60 percent increase since 1990
[3]. The World Health Organization, [4, 5] United States (US) Centers for
Disease Control and Prevention, [6, 7] and the International Obesity Task
Force [8] have some variation in the definitions of overweight and obesity in
children. Therefore at different ages, this can result in slightly different
estimations of the prevalence of overweight and obesity [9]. United Kingdom
(UK) definitions of overweight are based on comparisons of body mass index
(BMI) for age and sex on the UK 1990 growth reference (Table 1) [10].
Table 1. Levels of overweight/obesityOverweight >91st centile
Obese >98th centile (>2S.D)
Severely obese >99.6th centile (>2.67 S.D)
Very severely obese >3.5 S.D
Extremely obese >4 S.DIn the U.S. the definition is based on the standard growth charts developed
by the Centers for Disease Control and Prevention. In children and young
people aged 2 to 20 years old, a BMI in the 85th to 94th percentiles for age and
gender is considered overweight; a BMI in the 95th percentile or higher is
considered obese. Studies over the last three decades (up to around 2010) have
shown the frequency of childhood overweight and obesity to be on the
increase – some figures suggesting a tripling of numbers over the last few
decades [11]. The prevalence of child obesity in the U.S. was stable through
the 1960s and 1970s, but then began to rise in the 1980s. There were no
national surveys of child obesity prior to 1963. Authors von Hippel and
Nahhas used data from a local study near Dayton, Ohio, to extend the history
of child obesity back to the 1930s. Although girls’ BMIs were already
increasing in the 1930s, obesity among both boys and girls was very rare until
obesity prevalence started increasing after birth year 1970. The results are in
keeping with the theory that the obesity epidemic is primarily a recent
phenomenon [12]. The problem of obesity is not confined only to the