EAT FOR HEALTH – AusTRALiAn diETARy guidELinEs
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It is suggested that by 2011, 125 countries representing 75% of the world’s under–5 population had adopted the
WHO growth standards and were at varying stages of implementation.^1079 This includes the uS, Canada, uK and
New Zealand. The WHO growth standards for 0–19 years were implemented in the Northern Territory in 2009 and
Victoria implemented WHO charts for 0–2 years in 2011. In 2012, all Australian jurisdictions agreed to adopt the WHO
2006 growth charts as the standard for Australian children aged 0–2 years. They will be phased in by other states and
territories for use at the primary health care level in child health records. Education and training materials to assist
Australian health professionals in using the WHO Charts are being developed and will become available in 2013.
Other specialised growth charts may still be used by clinicians for groups with particular needs or characteristics.
Care should be taken to consider the differences between charts when assessing the growth of infants. The new
WHO growth standards (2006) are heavier than the CDC 2000 growth reference in the first 6 months of life but
lighter after 6 months.
Table H1: Practical points in the use of growth reference charts in infants aged 0–2 years
• Health professionals should use a growth reference chart appropriate to the age and sex of the infant or child and be aware which
chart they are using
• In using the WHO growth reference charts, it is important to note that the 2nd percentile corresponds approximately to the 5th percentile
on the CDC growth chart for infants under 6 months and that lower positions on the growth reference chart are acceptable
• In determining whether breast milk production or infant formula consumption is adequate (or for infants fed formula the amount is
excessive), growth trajectory is more important than position on the growth reference chart
CDC BMI curves
In Australia, the NHMRC Overweight and Obesity Guidelines^121 suggest the use of the uS CDC growth charts^1046
for monitoring growth in children and adolescents aged 2–18 years.35,1081 Overweight is categorised as between
the 85th and 95th percentiles in the BMI charts and obesity as above the 95th percentile.
However, use of the CDC charts has been criticised as they are based on uS data only, from five national surveys
undertaken between 1963 and 1994, the most recent being NHANES 111. The age- and sex-specific CDC growth
charts were last updated in 2000, and do not include weight data (and thus BMI data) from NHANES 111 from
children over 6 years of age.
BMI using international reference standards
BMI measurement is a low-cost, simple method that has been validated against more direct measures of adiposity.^1082
In 1999 an expert committee, on behalf of the IOTF, recommended that BMI be used to assess adiposity in children
and adolescents and that the adult cut-off points be used as a reference.1083,1084 However, normal BMI among children
and adolescents changes with age, so choosing a single cut-off number is not possible.
Following on from this recommendation, an international reference for defining overweight and obesity in children
and adolescents was developed with data from six countries, and provide age- and sex-specific BMI cut-off points
for children and adolescents aged 2–18 years that correspond to adult BMI values of 25 kg/m^2 for overweight and
30 kg/m^2 for obesity.^122 Designed for epidemiological use, the tables will allow international comparison of the
prevalence of overweight and obesity, as well as assessment of trends in children.1074,1085-1087
Other measurements
Waist circumference and waist:height ratio are becoming more common measures of child, adolescent and
adult central adiposity, but there is little consensus regarding standard cut-off values to define overweight
and obesity.130,1088-1093 A waist:height ratio equal to or less than half (ratio ≤ 0.5) may be useful in predicting
cardiovascular risk in children.1094-1097
Skinfold measurement – an index of subcutaneous adipose tissue – is another method of defining of under- or
over-nutrition.^1098 Reliable and accurate measurements depend to a large extent on the use of trained operators
and properly calibrated instruments.
Other methods of body composition assessment, for example dual energy X-ray absorptiometry, can provide
accurate measurements, but cost limits their application to experimental use and to clinical settings where more
accurate diagnosis is required for management.^1099 The most accurate measure of body composition is provided
by using doubly labelled water, but cost limits its use to research.