CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 9/10, October/November 2013
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AFRICA
SA context where there are the potentially confounding effects
of socio-economic status. Race has been defined by Williams
et al
.
14
as ‘a complex multidimensional construct reflecting
the confluence of biological factors and geographical origins,
culture, economic, political, and legal factors, as well as racism’.
In a recent commentary,
15
it was suggested that race and
ethnicity share a similar definition, however, the difference
between the two constructs lies in the fact that ethnicity is usually
defined by the group itself, whereas race is typically defined
by others outside ‘the group’. Culture, on the other hand, has
been defined as ‘the learned and shared beliefs, values, and life
ways of a designated or particular group which are generally
transmitted inter-generationally and influences one’s thinking and
action modes’.
15
For demographic and restitution purposes, the
Government currently classifies race into black (ethnic Africans),
white (Europeans, Jews and Middle Easterners), coloured or
mixed ancestry (mixed race) and Indian (South Asian).
Socio-economic status and education
Historically, black South Africans have been compromised in
terms of education, access to healthcare and earning capacity
under apartheid laws. This is still currently reflected in the
2008/2009 South African Living Conditions of Household
Survey (LCS),
16
in which it was demonstrated that 25% of black
households fell within the lowest quintile of annual household
consumption expenditure compared to 0.7% of white households,
whereas 81% of white households fell within the highest quintile
compared to 8.2% of black households. Differences in obesity
and disease prevalence between these ethnic groups may be
partly attributed to or mediated by these social inequalities.
17
Studies in developed countries have shown an inverse
relationship between socio-economic status and obesity,
18,19
however studies in SA,
12,20-22
as well as other SSA countries
23-26
show a consistent positive association between obesity and
socio-economic status. In these studies, obesity was positively
associated with access to clean water and electricity,
21,25
reduced
housing density,
22,25
as well as more money spent on food,
27
higher energy intake,
25
commuting by taxi/vehicle
28
and reduced
physical activity or increased sedentary behaviour,
22,28-31
factors
representing a transition towards a more Western lifestyle.
In addition, in many black African communities, obesity or
overweight may still be considered a sign of good health
and beauty, as well as affluence,
32,33
further impacting on the
relationship between socio-economic status and obesity.
On the other hand, level of education, although highly related
to socio-economic status has been shown to be independently
associated with obesity in SA and other SSA countries. Studies
in many SSA countries,
23,24,27
as well as regions in SA with lower
socio-economic status,
21
have shown a positive association
between level of education and obesity.
By contrast, results from the SADHS suggest that the
relationship between education and obesity is not linear, as
women with no education and women with a tertiary education
had a lower body mass index (BMI) than those with some
schooling.
12
This may reflect the wider distribution of both
education and socio-economic status in SA, which has recently
been re-classified as a middle-income country,
1
and which has
one of the highest GINI coefficients in the world, suggesting
extreme inequality with regard to poverty and wealth.
34
Gender
Studies in SA
12,20,21,35
and other SSA countries
23,25,26,28,29
have
consistently reported that the prevalence of obesity is greater in
women than men. Case and Menendez,
20
using data collected
from an informal urban settlement in SA, identified two factors
to explain the gender difference in obesity rates in their study:
(1) being nutritionally deprived as children; and (2) having a
higher socio-economic status. These factors were associated with
obesity in women, but not in men.
Traditionally, black SA households are strongly patriarchal,
with men holding a dominant position. For this reason, boys
have been better cared for and nourished as babies and infants, so
they do not necessarily experience the same level of nutritional
deprivation at a young age as girls.
36
However, due to migrant
labour and high death rates related to HIV/AIDS among young
adults, nearly half of all households in SA are headed by
women.
37
These households are among the poorest and most
marginalised.
16
In 2009, more than 20% of female-headed
households reported experiencing hunger (skipping meals or
running out of money) compared to only 15% of male-headed
households.
38
Urbanisation
Rural and urban black SA communities have historically faced
very different public health challenges, with infectious diseases
associated with under-nutrition prevalent in rural communities,
and a rising prevalence of NCDs associated with over-nutrition
in urban-dwelling communities.
30
This rural–urban gradient is
still present in most SSA countries,
30
but in SA, the disparities
between rural and urban settings are attenuated. The 2003
SADHS reported a 21% prevalence of obesity in rural black SA
women compared to 31% in urban black SA women.
Urbanisation is accompanied by the adoption of aWesternised
lifestyle, however in SA many cultural beliefs around lifestyle
behaviours and body image are retained.
36
Differences in diet
have been identified as one of the possible causes of urban–
rural differences in obesity prevalence,
39
and the term ‘nutrition
Fig. 1. A schematic representation of the inter-relation-
ships between the socio-cultural, behavioural and envi-
ronmental determinants of obesity in black South African
women discussed in this review.
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Obesity
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Maternal
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Body image
