Preventing Childhood Obesity - Evidence Policy and Practice.pdf

Chapter 33
Finally, within a given individual, namely a malnourished
young child, there can be a quick transition,
over a few years or even months, from being
wasted (underweight for height) to being overweight
or even obese (excess weight for height). Moreover, in
many cases, these children remain stunted (low height
for age), making them more vulnerable in an urban
setting to obesity and diabetes, both of which are
linked to excess body fat resulting from sedentary lifestyles
and consumption of high - energy density diets.
In fact, the model of the malnourished child during
recovery serves to illustrate many of the features of the
nutrition transition mirroring the rapid shift in diet
from low - to high - energy density food, as well as a
progressively sedentary life style, that moves stunted
populations from underweight to overweight and
obesity. 12
More recently, the influence of postnatal growth on
later development of obesity and nutrition - related
chronic disease has been documented. Postnatal
growth is clearly related to prenatal growth with some
of the metabolic changes associated with prenatal
nutritional sufficiency affecting postnatal physiology
13 – 15
and behavior which, in turn, affect growth. In
2005, Stein et al reviewed the evidence linking child
growth and chronic diseases in five cohorts from transitional
countries (China, India, Guatemala, Brazil
and the Philippines) concluding that growth failure in
early childhood and increased weight gain in later
childhood were associated with increased prevalence
of risk factors for cardiovascular disease (i.e. body
composition, blood pressure, glucose metabolism). 16
These results correspond to studies from cohorts that
originated in the 1970s and early 1980s. The clear
progression of the obesogenic environment in most
countries around the world suggests that the present
impact of these early life factors in determining
the rise in adult chronic diseases is likely to be
underestimated.
Postnatal growth, on the other hand, is also associated
with later adult disease independent of prenatal
growth. Studies from developed countries show a consistent
positive association between infant size and
later body size but inconsistent associations with later
disease. 17 In transitional countries, it is important to
clarify the relative importance of growth in different
postnatal periods in order to implement interventions.
In Brazil, India and Guatemala, growth in
infancy (0 – 1 years) and late childhood (over 2 years)
were described as critical periods predicting adult
body composition. Weight gain in infancy was related
to higher fat - free mass in adulthood, while rapid
weight gain in late childhood was associated with a
higher acquisition of fat mass. In India, greater
increases in body mass index ( BMI ) between 2 and 12
years were strongly associated with glucose intolerance
and Type 2 diabetes in adulthood. 15
Access to f ood, p overty and
c hildhood o besity
Income level is the main determinant of access to
food. The proportion of family income that is spent
on food serves to define the population income categories
in most developing countries. If family income
is less than the cost of one basic food basket the family
is defined as indigent; those with income below the
cost of two food baskets are classified as poor, in this
case they actually spend more than 50% of their
income on basic foods. 18
Food security depends on the households ’ access to
food rather than overall availability of food. In rural
areas, household food security depends mainly on
access to land and other agricultural resources which
facilitate domestic production. In urban areas,
however, food is mainly purchased in the market. A
variety of foods, therefore, needs to be available and
affordable in urban markets for adequate food security.
In most developing regions there is plenty of food
in the stores, yet families living under poverty conditions
are unable to buy food of sufficient quantity and/
or quality and thus will be food insecure. 19,20
Poverty and food insecurity go hand in hand. Food
security in poor households often fluctuates dramatically,
depending on changes in agricultural production
in response to seasonal and environmental
conditions. Fluctuating market prices affect poor producers
as well as the urban or rural poor. In an open
market economy, farmers and their families are also
affected by falling global market prices for food commodities.
In most cases, they depend on products they
place in the market and this means that their income
will vary with commodity prices which are beyond
their control. In the urban setting, the poor rely on
food purchases that are commonly affected by
rampant inflation. This income instability means that
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