Background

Both mental illness and household food insufficiency are common in low and middle income countries, but their relationship is not well defined. Results from the South African Stress and Health Study (SASH), the first nationally representative study of psychiatric morbidity in South Africa, indicate that approximately 30% of adults have experienced a Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) disorder in their lifetime.1 Food insecurity, the limited or uncertain availability of nutritionally adequate and safe foods or limited or uncertain ability to acquire acceptable foods in socially acceptable way,2 3 is also a major public health concern in the developing world. Of particular concern is food insufficiency, an extreme form of household food insecurity that refers to a condition in which household members sometimes or often do not have enough to eat.4–8 Food insufficiency is comparable to the concept of ‘food insecurity with hunger’.7 Data from the South African General Household Survey (2007)9 indicate that 6.3% of adults and 7.1% of children had gone hungry due to an inadequate amount of food available, while data from a nationally representative sample of children in South Africa estimated that, in 1999, 52% of households experienced hunger and 23% were at risk of hunger.10 However, at the present time there are no available data on the prevalence of household food insufficiency in the South African population.

There are a number of potential negative consequences of household food insecurity and insufficiency. Food insufficiency can affect physiological mechanisms that are linked to an individual's nutritional status.11 This was shown in a study by Dixon et al7 who found that adults in food-insufficient households were more likely to have diets that could compromise their health than adults from food-sufficient families. They also had lower serum concentrations of critical nutrients, which can lead to an increased risk of a number of major chronic diseases.7 Additionally, uncertainty about the availability of food, whether or not food insufficiency actually occurs, may affect the individual's social and mental well-being by creating feelings of aggravation, worry and depression concerning their food supplies.11 However, a challenge when researching the consequences of food insecurity is to distinguish its health consequences from those of risk factors such as poverty and low socioeconomic status with which it commonly co-occurs.11 12

Research conducted predominantly in developed countries has reported an association between household food insecurity or insufficiency and a number of negative health outcomes. These include nutrient inadequacies in adults and adolescents,13 14 poor self-reported health status,15 heart disease, diabetes and high blood pressure.16 Recently, Leyna et al17 estimated the prevalence of reported food insufficiency and its associated sociodemographic factors and health indicators among 899 participants in rural Tanzania. The results indicated that age, lower education, being a peasant, poor self-rated health status and having health problems were associated with food insufficiency only in women.

There is limited research on the relationship between food insufficiency and specific types of mental disorders. Some research has been carried out on the links between household food insecurity or insufficiency and mental disorders, most of which has focused on non-representative community surveys of respondents, including women,18–21 welfare recipients,22 23 HIV positive individuals24 and adolescents.25 26 The measures used to determine the mental health status of the participants were often symptom inventories such as symptoms checklists27 or the CES-D.21

Recent studies of nationally representative samples in the developed world confirm a relationship between food insufficiency and mental disorders.16 28 For example, in a nationally representative study conducted in Canada, individuals from food-insufficient households had significantly higher odds of not only reporting poor/fair health, of having poor functional health, restricted activity and multiple chronic conditions, but were also more likely to be suffering from major depression and symptoms of distress.

In the developing world there has been little research that has considered the role of food insufficiency in shaping mental health. It is important to examine this association within developing countries because food insecurity is a highly prevalent feature of life within many developing regions, and knowledge about the consequences of food insecurity may impact the development of social policies to protect vulnerable segments of the population. Within developing countries, only a few community studies have investigated this relationship, none using a nationally representative sample.19 27 29–31 The purpose of the present study is therefore to use the SASH dataset to estimate the prevalence of household food insufficiency, to identify demographic and socioeconomic characteristics of households most likely to report food insufficiency, and to examine the relationship between food insufficiency and mental disorders.

Discussion

The main results of this study are that: (1) 38% of South Africans report that their households are food-insufficient; (2) after controlling for conventional socioeconomic and sociodemographic variables, food insufficiency was associated with an increased risk of having a 12-month and lifetime DSM-IV diagnosis of anxiety disorder; and (3) respondents who reported that their household ‘often’ did not have enough food were also more likely to have a 12-month and lifetime substance use disorder than those who were food-sufficient.

High rates of food insecurity and food insufficiency have been reported in Tanzania17 19 36 and Ethiopia.27 37 For example, a recent study conducted in rural Ethiopia with 902 participants found that 33% of respondents were food-insecure.27 However, these studies were not national in scope and, to our knowledge, this is the first nationally representative study to document household food insufficiency in sub-Saharan Africa. The finding that 38% of South Africans reported household food insufficiency indicates a significant public health burden. To place this finding in perspective, nationally representative studies in the developed world estimated that only 2.3% of Canadians reported food insecurity with any type of hunger,38 while 4.1% of American households had ‘very low food security’ (conceptually similar to food insufficiency) in 2007.39

Second, data from this population-based representative sample revealed that food insufficiency was associated with having a 12-month DSM-IV diagnosis. Therefore, the 38% of South Africans who experience household food insufficiency not only face the risk of physical health problems associated with an inadequate diet and nutritional deficiencies, but also the risk of having a mental illness. This finding is consistent with results of previous community-based studies18 20 23 40 and the nationally representative studies conducted in the developed world.16 28 Of note, the pattern of results for the association between lifetime DSM-IV diagnosis and food insufficiency was almost identical with the findings for the 12-month DSM-IV outcome.

Respondents who reported food insufficiency were more likely to have a 12-month DSM-IV disorder—and specifically an anxiety disorder—than those who were food-sufficient. This analysis did not observe a significant increase in risk for major depressive disorder, which is inconsistent with previous research reporting an association between food insecurity and depression.19 27 As anxiety disorders are more common than depressive disorders in our sample, it is possible that the finding of an association of food insecurity with anxiety but not with depressive disorders simply reflects a false negative in the latter case. An alternative explanation might be that, in an African setting where food insecurity is widespread, there is more resilience to associated depression than in other contexts. Nevertheless, given that anxiety and depressive disorders are so often comorbid, and given that previous literature has shown that food insecurity is linked with both of these groups of disorders, the former explanation seems more persuasive.

Finally, respondents who reported that they ‘often’ did not have enough food were more likely to have a 12-month and lifetime substance use disorder than those who were food secure. Similar findings were reported in a study conducted in Canada assessing food insecurity among 1213 HIV-positive patients, where participants who reported ever having used recreational injection drugs and ever having had alcohol or drug treatment were more likely to be food insecure.24 Another study conducted in the USA compared food insecurity among 41 low-income Puerto Rican female out-of-treatment drug users and 41 matched controls. The results indicated that drug users were more likely than the controls to experience food insecurity according to the Radimer/Cornell scale.41 It could be that drug users prefer purchasing drugs than food when funds are available.

The relationship between food insufficiency and mental health has implications for reducing the burden of common mental disorders in South Africa. Mental disorders and their associated psychosocial disabilities are a source of considerable morbidity and impose a significant drain on national resources.42 If food insufficiency is a contributing or causal factor in mental illness, preventing it might reduce the risk of onset or recurrence of these costly and disabling illnesses. Many of the major risk factors for mental illness that have been identified in the literature such as low socioeconomic status and genetic factors cannot be readily modified. However, food insufficiency is relatively amenable to intervention. Nutrition education programmes could include mental health screening and mental healthcare providers could screen for food insecurity as part of the psychosocial evaluation. Non-governmental organisations and governmental programmes presently active in South Africa providing food assistance, including the distribution of food parcels, could be used more effectively.

Several limitations of this study must be considered when interpreting these findings. First, although our theoretical perspective suggests the hypothesis that food insufficiency leads to psychiatric disorder, it must be emphasised that the cross-sectional design of our study and many other studies on this topic18 22 43 does not provide information about the causal direction of associations. Although it might be argued that household food insufficiency predisposes individuals to poor mental health, the reverse could also be true. Prospective research in the USA provides support for a bidirectional relationship, where food insecurity predicted depression and depression predicted food insecurity.29 Second, despite the evidence suggesting that food insufficiency increases HIV risk transmission behaviours and susceptibility to HIV once exposed,44 and that people living with HIV/AIDS (PLWHA) are twice as likely to suffer from a psychiatric disorder than the general population,45 an analysis of the association between HIV and food insufficiency was not conducted owing to low self-reported prevalence rates. However, the covariate for self-reported health status should capture some of the variation that may be related to HIV status. Finally, since data were not collected from non-respondents, we know very little about the 15% who refused to participate in the SASH study.

Nevertheless, these data are the first to describe the association between food insufficiency and diagnostic mental health outcomes in a nationally representative population in a low or middle income country. These findings suggest that secure access to food may have health impacts that extend beyond nutritional outcomes to mental health status. These findings also demonstrate the necessity to continue efforts to prevent food insecurity in order to improve the health of South Africans. Our findings highlight the need for more research to better delineate the mechanisms and to test the effects of nutritional interventions.