Preventing Childhood Obesity - Evidence Policy and Practice.pdf

Chapter 16
obesity and that this may be moderated by social
policies.
Studies of measures of poverty or financial
s tress and o besity in t he USA
A number of US studies have demonstrated a modest
but consistent association between food insecurity
and weight status in adult women. This association
and the case report published by Dietz in 1995 has
stimulated a number of investigations of the association
between household food insecurity and weight
status in children. 21 While many of the studies cannot
provide evidence of causal relationship, owing to limitations
in study design and measurement, these
studies generally find only limited evidence of any
relationship between food insecurity and child overweight.
In secondary data analysis of nationally representative
US datasets, Casey 22 found no relationship
between food insecurity and weight status independent
of income, Alaimo 23 found that white girls aged
8 – 16 were slightly more likely to be overweight if they
lived in a food insufficient household, and Rose 24
found that kindergarten children were less likely to be
overweight if they were living in a food insecure
household.
The few smaller studies published have also reported
inconsistent and weak evidence of associations
between food insecurity and child weight status.
Matheson and colleagues 25 reported a lower BMI
among children in food insecure households in a
cross - sectional sample of 124 Hispanic families, but
Kaiser26 reported no association in another sample of
younger Hispanic children. At the time of writing,
there is only one published study that examines the
longitudinal associations between food insecurity and
overweight. Jyoti 27 found that girls from food insecure
households had greater gains in BMI than girls from
food secure households, but average BMI remained
within the normal range. There are a number of plausible
explanations for the lack of a clear association
between food insecurity and obesity in children. It is
possible that children, particularly young boys, are
protected from food insecurity through their parents ’
coping strategies. It is also possible that programs
available to protect children from the effects of household
food insecurity are working, in that children are
receiving adequate and healthy meals from school and
child care environments.
Studies in other developed economies
Other than the USA, there are few countries with
developed economies in which the relationship
between food insecurity and childhood obesity has
been measured. One country in which this research
has been undertaken is Canada.
Canada ’ s National Population Health Survey 1998 –
1999 found that 11% of children < 18 years lived in
households where food insecurity compromised diet.
In this survey, children were five times more likely
than seniors to be living in a food insecure household.
28 Using data from the Longitudinal Study of
Child Development, Dubois 29 found that the presence
of family food insufficiency during preschool years
increased the likelihood of overweight three - fold after
adjusting for income. This study reported that low
birthweight children living in households that experienced
food insufficiency during preschool years were
at higher risk of becoming overweight at 4 – 5 years.
Implications for research and practice
There is evidence that an association exists between
socio - economic disadvantage, poverty and obesity in
children. It would appear that social policy can influence
the socio - economic conditions in which children
live and lessen the likelihood of a child becoming
obese. Evidence for an association between food insecurity
and obesity is less consistent and may be
country dependent. While a very strong association
has been demonstrated in Canada, the US results indicate
a weaker link. Again, these differences may reflect
different social policies in each of these countries that
moderate either the likelihood of a household being
food insecure or the impact of food insecurity on a
child ’ s health and relative body weight.
Where do we go from here? We need to improve
our understanding of both how to reduce childhood
poverty and disadvantage and also how to develop
policies that can target solutions in the pathways
between poverty and obesity in children. Research
should be directed at understanding these pathways
using cross - national and longitudinal comparisons.
To best articulate policy regarding either childhood
obesity or food insecurity, countries with developed
economies need research that goes beyond examining
associations of food insecurity and obesity in children.
For instance, in the USA, a number of policies have
been developed and programs implemented to address
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