This study has a number of important findings on the dietary patterns of children living in an area with an extremely high prevalence of HIV and on the methods used to determine dietary diversity. Chief among these is that HIV-infected children have lower dietary diversity between 6 and 24 mo of age than HIV-uninfected children. This difference was present both in bivariate analysis when compared with HIV-uninfected children born to HIV-uninfected mothers and when controlling for socioeconomic status, recall period, and diarrheal and respiratory morbidity. Children without HIV infection born to HIV-infected mothers had a diminished dietary diversity compared with children born to mothers without HIV infection, but this difference did not reach significance.
The association of HIV infection and lower dietary diversity in a multiple-regression including diarrhea and respiratory infection as covariates suggests that the lower dietary diversity in HIV-infected children cannot be explained only by increased frequency of disease episodes. It might be related to difficult to conditions (especially in infants and young children), such as poorer appetite, or unmeasured aspects of socioeconomic status, such as household income. Poor appetite with inadequate dietary intake has been well documented in HIV-infected children (22
). Increased levels of tumor necrosis factor-a may be involved in the appetite inhibition (24
). Neurodevelopmental delay and decreased maternal well-being may be additional factors leading to low energy intake and concomitant low dietary diversity. Because we did not measure energy intake, we were unable to determine whether the association between HIV and dietary diversity disappears when energy intake is introduced in the model. If that were the case, it would suggest that energy intake reduction was indeed the main mechanism by which HIV exerts its effect on dietary diversity.
HIV-infected children in this study, compared with HIV-uninfected children born to either HIV-infected or HIV-uninfected mothers, consumed fewer food classes in the first year of life with the exception of breast milk. This may be because children who were known to be HIV-infected at 6 mo of age were encouraged to continue breast-feeding. However, we cannot exclude a survival bias affecting this finding, because breast-fed, HIV-infected children may have been more likely to survive to 6 mo of age, when our observations began.
The pattern of dietary diversity identified in this study is one of rapidly increasing diversity in the seecond half of the first year of life in infants in all 3 HIV status groups. Although infants progressively abandon breast milk and formula, diversity increases because they replace it with nonmilk sources of protein, snacks, and sweetened beverages. Although increasing diversity is often thought of as beneficial in and of itself, the decline in breast-feeding after 6 mo of age has important health implications even though overall dietary diversity is increasing. The health benefit of continued breast-feeding after 6 mo of age for children of HIV-uninfected mothers is well documented (25
). Dietary diversity could be further enhanced in this population by reinforcing breast-feeding by HIV-uninfected mothers. Indeed, the observed pattern of breast-feeding was not optimal. Already at age 6 mo, 1 of 4 HIV-uninfected children was no longer receiving any breast milk. In y 2 of life, breast milk consumption continued to decrease rapidly so that by age 18 mo, 3 of 4 children were not receiving breast milk.
Another concern in the diet of this population is the low consumption of fruits and vegetables. In more than one-half of the observed child weeks, no fruit or vegetable was consumed. Although there may have been some underreporting of fruit and vegetable consumption, this is unlikely to explain the low consumption. The area where this study was conducted has little subsistence farming and is very poor. Poor households are known to spend a disproportionate portion of their income on staple foods, primarily maize meal, and fruits and vegetables are generally considered less essential and are more expensive. This may increase the risk of micronutrient deficiencies (4
). The South African government has initiated a staple food fortification program to decrease the risk of micronutrient deficiencies in the population (26
). Nevertheless, campaigns to promote subsistence farming could be very helpful to increase the consumption of fruits, vegetables, and animal-source food (27
The reliance on purchased foods in this population may also explain why we did not find any seasonal variation in dietary diversity. This is not a typical situation in sub-Saharan Africa where periodic food insecurity is frequent. For example, in a study of adult women in Burkina Faso, diversity of the family diet was found to fluctuate heavily due to periods of general food shortage (28
An intriguing finding of this study was that dietary diversity increased when the mother was not the main caregiver. This may appear counterintuitive and could in part be due to respondent bias by the replacement caregivers. Alternative explanations are that mothers who travel for whatever reason tend to make provisions to ensure an optimal diet for their child during their absence, that if the mother is away it is more likely that she is working and there is more family income to make these provisions possible, or that the replacement caregivers, often the grandmothers, tend to “spoil” the children. The latter explanation seems a good possibility, because in the study area, old age pensions constitute a major source of family income.
There are no universally accepted standardized tools for studying dietary diversity. Reports of studies that have described the association between dietary diversity and energy or nutrient intake have also invariably recommended the development and refinement of indices of dietary diversity (6
). The method we have introduced to assess dietary diversity in young children should be relatively easy to reproduce in other settings, because the questionnaire is relatively short and locally adaptable. If this survey was to be adapted for use in other settings, an initial pilot study of the target population is needed to identify foods that are commonly consumed within each of the 8 food classes. An internal standardization of the weekly dietary diversities for age, sex, and season should be easy to perform using the same method as we describe.
Other advantages of the method we used include the fact that it allows collection of daily dietary intake information. It also allows monitoring of dietary diversity over longer periods than with more traditional dietary surveys. Those traditional surveys are more intensive and require longer to complete and thus are more difficult to sustain over time. The diets of children <2 y of age are constantly changing as more foods become available to the maturing child. This makes it more relevant to collect information daily or weekly to overcome large between- and within-person variation.
This study focused on exploring determinants of dietary diversity in young children, primarily examining the effect of HIV status. The functional validity and usefulness of dietary diversity measures needs further study both in children and adults (6
). Little is known about the possible effects of low dietary diversity on growth and health outcomes. Such studies should ideally also quantify total energy intake so that the independent effects of diet diversity and energy intake can be assessed. It has been suggested that exploration of such relationships should also adjust for socioeconomic variables (31
). An 11-country demographic survey found that dietary diversity was significantly associated with attained height even after adjusting for socioeconomic and other confounding factors (4
In conclusion, this study shows that the diets of HIV-infected children are significantly less diverse than those of HIV-uninfected children born to HIV-uninfected mothers and of those of HIV-infected children born to HIV-infected mothers. Such lack of diversity may contribute to the development of specific nutrient deficiencies (3
) and may be a factor contributing to increased morbidity and poorer survival in these children.