SCN News No 36 - UNSCN

www.unsystem.org/scn FEATURES 13
In general, the prevalence of severe wasting is higher at younger ages and then declines and reaches a
plateau by 24 months. Conversely, stunting prevalence increases progressively until reaching a plateau at
around 24 months of age (WHO 2008a). In a recent analysis, severe wasting was not accompanied by
stunting in 80-100% of younger children and 40-50% of older children (Black et al 2008). Thus, identifying
children who are stunted will not capture most of those who suffer from severe wasting. In addition, stunting
and severe wasting are not necessarily associated on a geographical basis, that is, countries with a similar
stunting rate can have considerably different prevalence of severe wasting (WHO 2008a).
The great magnitude of undernutrition, which continues to hamper the growth and development of one third of
the world's children, threatening their very survival, is unacceptable given the solid evidence that children from
different areas and ethnic backgrounds experience very similar patterns of linear growth provided they are
raised under appropriate environmental conditions (mainly proper feeding practices and free of infections).
This has been shown by several studies, and more recently reconfirmed by the WHO Multicentre Growth
Reference Study, where the length of children was strikingly similar among the six study sites (Figure 1) with
only about 3% of variability in length being due to inter-site differences compared to 70% for individuals within
sites (WHO Multicentre Growth Reference Study Group 2006). The striking similarity in growth during early
childhood across human populations means either a recent common origin as some suggest (Rosenberg et al
2002) or a strong selective advantage associated with the current pattern of growth and development across
human environments.
Projections of childhood stunting to 2015
At the Millennium Summit in 2000, representatives from 189 countries committed themselves towards a world
in which sustaining development and eliminating poverty would have the highest priority. The increased
recognition of nutrition as a basic pillar for social and economic development placed childhood undernutrition
among the targets of the first Millennium Development Goal, "to eradicate extreme poverty and
hunger" (United Nations 2002). The specific target goal is to reduce by 50% the prevalence of underweight
among children younger than 5 years between 1990 and 2015.
Monitoring progress towards the MDG targets, requires reliable and standardized data collection systems that
enable comparison over time. In an effort to monitor progress towards MDG1, we presented in 2004 estimates
of global and regional trends of childhood underweight to 2015 (de Onis et al 2004b). We have since been
asked how progress would be if we were to use the indicator of stunting instead of underweight. With the
occasion of the 35 th SCN Session we presented these results, based on analyses of 388 national surveys from
139 countries applying the same methodology as before (de Onis et al 2004b) and using the new WHO Child
Growth Standards (WHO 2006). The great majority of the surveys were re-analyzed to obtain the stunting
estimates based on the WHO
Figure 1: Mean length (cm) from birth through two years for each of the 6 study sites. standards; however, for surveys for
which the raw data were not available,
Brazil
Ghana
the estimates were derived applying
India
Norway
an algorithm that allows converting
Oman
USA
estimates of child stunting based on
the NCHS reference into estimates
based on the WHO Child Growth
Standards (Yang and de Onis 2008).
Figure 2 presents projections of
prevalence of stunting for 2015
compared with the MDG estimate. An
overall improvement in the global
situation is anticipated; however,
neither the world as a whole, nor the
developing regions, are expected to
Mean of Length (cm)
50 60 70 80
0 200 400 600
Age (days)
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