Dietary intake of low-income adults in South Africa: ultra-processed food consumption a cause for concern

OBJECTIVE

Given the rapidly changing food environment and proliferation of ultra-processed foods (UPF) in South Africa (SA), this study aimed to critically evaluate dietary quality and adequacy of low-income adults using the Nova classification system and WHO and World Cancer Research Fund dietary guidelines.

DESIGN

Secondary household data and 1-d 24-h recalls were analysed from two cross-sectional studies conducted in 2017-2018. Foods consumed were classified according to the Nova classification system. Compliance with WHO dietary guidelines and UPF consumption trends were evaluated.

SETTING

Three low-income areas (Langa, Khayalitsha and Mount Frere) in SA were included.

PARTICIPANTS

In total, 2521 participants (18-50 years) were included in the study.

RESULTS

Participants had a mean energy intake of 7762 kJ/d. Most participants were within the acceptable WHO guideline range for saturated fat (80·4 %), total fat (68·1 %), Na (72·7 %) and free sugar (57·3 %). UPF comprised 39·4 % of diets among the average adult participant. Only 7·0 % of all participants met the WHO guideline for fruit and vegetables and 18·8 % met the guideline for fibre. Those within the highest quartile of share of energy from UPF consumed statistically higher amounts of dietary components to limit and were the highest energy consumers overall.

CONCLUSIONS

Low-income adults living in SA are consuming insufficient protective dietary components, while UPF consumption is prevalent. Higher UPF consumers consume larger amounts of nutrients linked to increased chronic disease risk. Policy measures are urgently needed in SA to protect against the proliferation of harmful UPF and to promote and enable consumption of whole and less UPF.

Decomposing consumer and producer effects on sugar from beverage purchases after a sugar-based tax on beverages in South Africa

Growing global concern about obesity and diet-related non-communicable diseases has raised interest in fiscal policy as a tool to reduce this disease burden and its social costs, especially excise taxes on sugar-sweetened beverages (SSBs). Of particular interest have been nutrient-based taxes to improve diet quality. These can incentivize producers to reformulate existing products and introduce healthier alternatives into their ranges. In 2018, South Africa adopted a sugar-based tax on SSBs, the Health Promotion Levy (HPL). Early findings suggest that purchases of higher-sugar taxable beverages fell and purchases of no- and lower-sugar beverages increased, alongside significant reductions in the sugar content of overall beverage purchases. However, underlying these changes are consumption shifts as well as product reformulation and changes in producers' product portfolios. Drawing on a household scanner dataset, this study employed a descriptive approach to decompose changes in the sugar content of households' non-alcoholic beverage purchases into producer factors (reformulation and product entry and exit) and consumer factors (product switching and volume changes as a result of price changes, changing preferences, or other factors). We look at these factors as the tax was announced and implemented across a sample of over 3000 South African households, and then by Living Standard Measures (LSM) groups (middle vs. high). The sugar content of beverage purchases fell by 4.9 g/capita/day overall, a 32% decrease. Taken in isolation, consumer switching and volume changes together led to a reduction equivalent to 71% of the total change, while reformulation accounted for a decrease equal to 34% of that change. Middle-LSM households experienced larger reductions than high-LSM households due to larger changes on the consumer side. For both LSM groups, reformulation-led reductions mostly occurred after implementation, and most changes came from taxable beverage purchases. As sugary drink tax designs evolve with broader implementation globally, understanding both supply- and demand-side factors will help to better assess the population and equity potential of these policies.

South Africa's Health Promotion Levy on Pricing and Acquisition of Beverages in Local Spazas and Supermarkets

OBJECTIVE

In response to concern over rising sugar-sweetened beverage (SSB) consumption, in April 2018, South Africa became the first Sub-Saharan African country to implement an SSB tax. We assess changes in pricing and acquisition of beverages from local supermarkets and small stores among 18-39 year old adults living in one township in the Western Cape, before and after tax implementation. This study is among the first evaluations of an SSB tax on the local food environment in a low-income township.

DESIGN

Store beverage pricing and participant surveys were cross-sectional, analyzed 1 month before and 11 months after implementation of the tax (March 2018 and March 2019).

SETTING

Langa, Western Cape, South Africa.

PARTICIPANTS

Surveyed participants were residents of Langa between 18-39 years old (N=2,693 in 2018 and N=2,520 in 2019).

RESULTS

Prices of taxed SSBs increased significantly among small shops and supermarkets between 2018 and 2019. There were non-significant decreases in prices of untaxed beverages in small shops, but prices of untaxed beverages increased in supermarkets. Across all store types, there was a 9 percentage point decrease in the probability of purchasing regular soda weekly pre/post-implementation. Reductions in purchasing were larger in small shops than supermarkets.

CONCLUSIONS

We found some differential impacts of the levy on pricing and acquisition of beverages by retailer type in one low-income township. As other Sub-Saharan African countries consider similar fiscal policies to curb soda consumption, obesity and related diseases, this work can be used to understand the implications of these policies in the retail setting.

Applying and comparing various nutrient profiling models against the packaged food supply in South Africa

OBJECTIVE

This study aimed to apply the newly developed Chile Adjusted Model (CAM) nutrient profiling model (NPM) to the food supply in South Africa (SA) and compare its performance against existing NPMs as an indication of suitability for use to underpin food policies targeted at discouraging consumption of products high in nutrients associated with poor health.

DESIGN

Cross-sectional analysis of the SA packaged food supply comparing the CAM to three other NPMs: SA health and nutrition claims (SA HNC), Chilean warning octagon (CWO) 2019, and Pan-American Health Organization (PAHO) NPM.

SETTING

The SA packaged food supply based on products stocked by supermarkets in Cape Town, SA.

PARTICIPANTS

Packaged foods and beverages (N=6474) available in 2018 were analyzed.

RESULTS

49% of products contained excessive amounts of nutrients of concern (considered non-compliant) according to the criteria of all four models. Only 10.9% of products were not excessive in any nutrients of concern (considered compliant) according to all NPMs evaluated. The CAM had an overall non-compliance level of 73.2%, and was comparable to the CWO 2019 for foods (71.2% and 71.1% respectively). The CAM was the strictest NPM for beverages (80.4%) due to the criteria of non-sugar sweeteners and free sugars. The SA HNC was the most lenient with non-compliance at 52.9%. This was largely due to the inclusion of nutrients to encourage, which is a criterion for this NPM.

CONCLUSION

For the purpose of discouraging products high in nutrients associated with poor health in SA, the CAM is a suitable NPM.

South Africa's Health Promotion Levy: Excise tax findings and equity potential

In 2016, the South African government proposed a 20% sugar-sweetened beverage (SSB) tax. Protracted consultations with beverage manufacturers and the sugar industry followed. This resulted in a lower sugar-based beverage tax, the Health Promotion Levy (HPL), of approximately 10% coming into effect in April 2018. We provide a synthesis of findings until April 2021. Studies show that despite the lower rate, purchases of unhealthy SSBs and sugar intake consumption from SSBs fell. There were greater reductions in SSB purchases among both lower socioeconomic groups and in subpopulations with higher SSB consumption. These subpopulations bear larger burdens from obesity and related diseases, suggesting that this policy improves health equity. The current COVID-19 pandemic has impacted food and nutritional security. Increased pandemic mortality among people with obesity, diabetes, and hypertension highlight the importance of intersectoral public health disease-prevention policies like the HPL, which should be strengthened.

A Fit-for-Purpose Nutrient Profiling Model to Underpin Food and Nutrition Policies in South Africa

South Africa (SA) is facing a rising prevalence of obesity and diet-related chronic diseases. The government is seeking to develop effective, evidence-based policy measures to address this. A well-designed, fit-for-purpose nutrient profiling model (NPM) can aid policy development. The aim of this study was to develop a fit-for-purpose NPM in SA. Steps included: (1) determining the purpose and target population; (2) selecting appropriate nutrients and other food components to include; (3) selecting a suitable NPM type, criteria and base; and (4) selecting appropriate numbers and thresholds. As part of the evaluation, the nutritional composition of packaged foods containing nutritional information (n = 6747) in the SA food supply chain was analyzed, a literature review was undertaken and various NPMs were evaluated. Our findings indicated that it is most appropriate to adapt an NPM and underpin regulation with a restrictive NPM that limits unhealthy food components. The Chile 2019 NPM was identified as suitable to adapt, and total sugar, saturated fat, sodium and non-sugar sweetener were identified as appropriate to restrict. This NPM has the potential to underpin restrictive policies, such as front-of-package labelling and child-directed marketing regulations in SA. These policies will support the fight against obesity and NCDs in the country.

Towards unified and impactful policies to reduce ultra-processed food consumption and promote healthier eating

The global surges in obesity and nutrition-related non-communicable diseases (NCDs) have created a need for decisive new food policy initiatives. A major concern has been the impact of ultra-processed foods (UPFs) and ultra-processed drinks on weight gain and on the risk of several NCDs. These foods, generally high in calories, added sugar, sodium, and unhealthy fats, and poor in fibre, protein, and micronutrients, have extensive negative effects on human health and on the environment (due to their associated carbon emission and water use). There is a growing tendency worldwide, and especially in South America, for food companies to add micronutrients to UPFs to make health claims regarding these products, to which food-regulating authorities refer to fake foods. Although more than 45 countries and smaller subregional or urban entities have created taxes on ultra-processed drinks, such as sugar-sweetened beverages, only a few have adopted taxes on snacks and other UPFs, and none have added major subsidies for truly healthy, fresh or minimally processed food for people from lower socioeconomic backgrounds. Another major focus has been on developing effective package labelling. A smaller number of countries have selected the most impactful warning labels and linked them with other measures to create a mutually reinforcing set of policies; a few other countries have developed effective school food policies. We herein present in-depth results from key countries involved in all these actions and in comprehensive marketing controls, and conclude with our recommendations for the future. This field is quite new; progress to date is substantial, but much more is left to learn.

Use of social media platforms by manufacturers to market breast-milk substitutes in South Africa

In South Africa (SA), exclusive breast feeding remains rare, with breast-milk substitutes (BMS) commonly being used in ways that are detrimental to infant and young child nutrition, health and survival. The use of internet, digital and mobile platforms has increased, including in low-income and middle-income countries, like SA and these platforms are avenues for BMS marketing. SA has national legislation (Regulation R991) to enforce the International Code of Marketing of BMS. This paper aims to provide pertinent examples of how BMS manufacturers in SA use social media to market their products thus violating national regulations. A digital (and social media) ethnography approach was used to study BMS organisations' activity on Facebook and Instagram. Purposively selected examples of social media posts observed (from 2015 to 2019) were included, and content analysed in terms of national legislation. Several examples of BMS social media marketing are presented and interpreted according to provisions of national regulations that they violate. BMS manufacturers have found ways on social media to market their products in a media space that is complex to regulate, and where it is difficult to enforce national regulations. It is necessary to engage with stakeholders, notably social media companies, to alert them to relevant regulations applicable to their platforms. Monitoring the marketing of products for infants and young children by national governments needs to include online and digital platforms especially social media.

Changes in beverage purchases following the announcement and implementation of South Africa's Health Promotion Levy: an observational study

BACKGROUND

In 2016, South Africa announced an intention to levy a tax on sugar-sweetened beverages (SSBs). In 2018, the country implemented an SSB tax of approximately 10%, known as the Health Promotion Levy (HPL). We aimed to assess changes in the purchases of beverages before and after the HPL announcement and implementation.

METHODS

We used Kantar Europanel data on monthly household purchases between January, 2014, and March, 2019, among a sample of South African households (n=113 653 household-month observations) from all nine provinces to obtain per-capita sugar, calories, and volume from taxable and non-taxable beverages purchased before and after the HPL announcement and implementation. We describe survey-weighted means for each period, and regression-controlled predictions of outcomes and counterfactuals based on pre-HPL announcement trends, with bootstrapped 95% CIs, and stratify results by socioeconomic status.

FINDINGS

Mean sugar from taxable beverage purchases fell from 16·25 g/capita per day (95% CI 15·80-16·70) to 14·26 (13·85-14·67) from the pre-HPL announcement to post-announcement period, and then to 10·63 g/capita per day (10·22-11·04) in the year after implementation. Mean volumes of taxable beverage purchases fell from 518·99 mL/capita per day (506·90-531·08) to 492·16 (481·28-503·04) from pre-announcement to post announcement, and then to 443·39 mL/capita per day (430·10-456·56) after implementation. Across these time periods, there was a small increase in the purchases of non-taxable beverages, from 283·45 mL/capita per day (273·34-293·56) pre-announcement to 312·94 (296·29-329·29) post implementation. When compared with pre-announcement counterfactual trends, reductions in taxable beverage purchase outcomes were significantly larger than the unadjusted survey-weighted observed reductions. Households with lower socioeconomic status purchased larger amounts of taxable beverages in the pre-announcement period than did households with higher socioeconomic status, but demonstrated bigger reductions after the tax was implemented.

INTERPRETATION

The announcement and introduction of South Africa's HPL were followed by reductions in the sugar, calories, and volume of beverage purchases.

FUNDING

Bloomberg Philanthropies, International Development Research Centre, South African Medical Research Council, and the US National Institutes of Health.

Examining the news media reaction to a national sugary beverage tax in South Africa: a quantitative content analysis

BACKGROUND

South Africa was the first sub-Saharan African country to implement a sugar-sweetened beverage (SSB) tax called the Health Promotion Levy (HPL) in April 2018. Given news media can increase public awareness and sway opinions, this study analyzed how the media represented the HPL, including expressions of support or challenge, topics associated with the levy, and stakeholder views of the HPL.

METHODS

We performed a quantitative content analysis of online South African news articles related to the HPL published between January 1, 2017 and June 30, 2019. We coded the presence or absence of mentions related to health and economic effects of the HPL and HPL support or opposition. Prevalence of these mentions, overall and by source (industry, government, academics, other), were analyzed with Pearson χ2 and post-hoc Fisher exact tests.

RESULTS

Across all articles, 81% mentioned health, and 65% mentioned economics topics. 54% of articles expressed support, 26% opposition, and 20% a balanced view of the HPL. All sources except industry expressed majority support for the HPL. Health reasons were the most common justifications for support, and economic harms were the most common justifications for opposition. Statements that sugar intake is not related to obesity, the HPL will not reduce SSB intake, and the HPL will cause industry or economic harm were all disproportionately high in industry sources (92, 80, and 81% vs 25% prevalence in total sample) (p < 0.001). Statements that sugar intake is related to obesity and non-communicable diseases were disproportionately high in both government (46 and 54% vs 31% prevalence in total sample) (p < 0.001) and academics (33 and 38% vs 25% prevalence in total sample) (p < 0.05). Statements that the HPL will improve health and the HPL will reduce health care costs were disproportionately high in government (47% vs 31% prevalence in total sample) (p < 0.001) and academics (44% vs 25% prevalence in total sample) (p < 0.05), respectively.

CONCLUSIONS

Industry expressed no support for the HPL, whereas academics, government, and other sources mainly expressed support. Future studies would be improved by linking news media exposure to SSB intake data to better understand the effects news media may have on individual behavior change.

The association between dietary consumption, anthropometric measures and body composition of rural and urban Ghanaian adults: a comparative cross-sectional study

Background

Overweight and obesity have become threats to public health in all regions across the globe including sub-Saharan Africa where prevalence used to be low. Policies to regulate the food environment and promote healthy food consumption look promising to reducing the prevalence of obesity but in Ghana there is not enough data to elicit a policy response. This study assessed the association between dietary consumption, anthropometric measures, body composition and physical activity among rural and urban Ghanaian adults.

Methods

This was a cross-sectional study involving 565 Ghanaian adults. Structured interviewer administered questionnaires were used to collect information on socio-demographics. Dietary consumption was assessed using household food frequency questionnaire and 24-h recall. Height, weight, BMI, waist circumference and body composition of all participants were determined. The World Health Organization’s Global Physical Activity Questionnaire (GPAQ) was used to assess physical activity levels. Mann-Whitney U test was used to analyze differences in anthropometric measures, body composition and consumption among rural and urban participants. Principal component analysis was used to analyze household food frequency data and nutrient analysis template was used to analyze 24-h recall. Chi-square was used to measure differences in obesity prevalence by community and gender. Multinomial logistic regression was used to model the risk factors associated with obesity.

Results

The prevalence of overweight and obesity using BMI were 29.9 and 22.9% respectively. Use of waist circumference measurement resulted in the highest overall obesity prevalence of 41.5%. Prevalence of obesity was higher among females compared to males across all measures with the exception of visceral fat that showed no significant difference. Four different patterns were derived from principal component analysis. Among urban participants, the staple pattern showed a significant negative correlation with visceral fat (r − 0.186, p-value 0.013) and BMI (r − 0.163, p-value 0.029). Multinomial logistic regression revealed that males (AOR 19.715, CI 9.723–39.978, p-value < 0.001) had higher odds of being of normal weight compared to females.

Conclusion

Prevalence of overweight and obesity continue to rise in Ghana, especially among females. Public education and screening as well as interventions that regulate the food environment and make affordable and available healthy food options are needed to control the rise in obesity prevalence.

Baseline predictors of sputum culture conversion in pulmonary tuberculosis: importance of cavities, smoking, time to detection and W-Beijing genotype

BACKGROUND

Time to detection (TTD) on automated liquid mycobacterial cultures is an emerging biomarker of tuberculosis outcomes. The M. tuberculosis W-Beijing genotype is spreading globally, indicating a selective advantage. There is a paucity of data on the association between baseline TTD and W-Beijing genotype and tuberculosis outcomes.

AIM

To assess baseline predictors of failure of sputum culture conversion, within the first 2 months of antitubercular therapy, in participants with pulmonary tuberculosis.

DESIGN

Between May 2005 and August 2008 we conducted a prospective cohort study of time to sputum culture conversion in ambulatory participants with first episodes of smear and culture positive pulmonary tuberculosis attending two primary care clinics in Cape Town, South Africa. Rifampicin resistance (diagnosed on phenotypic susceptibility testing) was an exclusion criterion. Sputum was collected weekly for 8 weeks for mycobacterial culture on liquid media (BACTEC MGIT 960). Due to missing data, multiple imputation was performed. Time to sputum culture conversion was analysed using a Cox-proportional hazards model. Bayesian model averaging determined the posterior effect probability for each variable.

RESULTS

113 participants were enrolled (30.1% female, 10.5% HIV-infected, 44.2% W-Beijing genotype, and 89% cavities). On Kaplan Meier analysis 50.4% of participants underwent sputum culture conversion by 8 weeks. The following baseline factors were associated with slower sputum culture conversion: TTD (adjusted hazard ratio (aHR) = 1.11, 95% CI 1.02; 1.2), lung cavities (aHR = 0.13, 95% CI 0.02; 0.95), ever smoking (aHR = 0.32, 95% CI 0.1; 1.02) and the W-Beijing genotype (aHR = 0.51, 95% CI 0.25; 1.07). On Bayesian model averaging, posterior probability effects were strong for TTD, lung cavitation and smoking and moderate for W-Beijing genotype.

CONCLUSION

We found that baseline TTD, smoking, cavities and W-Beijing genotype were associated with delayed 2 month sputum culture. Larger studies are needed to confirm the relationship between the W-Beijing genotype and sputum culture conversion.

The effect of vitamin A and zinc supplementation on treatment outcomes in pulmonary tuberculosis: a randomized controlled trial

BACKGROUND

Low serum concentrations of vitamin A and zinc are common in tuberculosis and may have an adverse effect on host cell-mediated responses. The role of adjunctive micronutrient supplementation on treatment outcomes is uncertain.

OBJECTIVE

The objective was to assess the efficacy of vitamin A and zinc supplementation on sputum smear and culture conversion and time to culture detection in adults with sputum smear-positive pulmonary tuberculosis.

DESIGN

Participants attending a primary care tuberculosis clinic in Cape Town, South Africa, were randomly assigned to receive micronutrients (single dose of 200,000 IU retinyl palmitate plus 15 mg Zn/d for 8 wk) or matching placebo. Sputum was collected weekly for 8 wk for auramine staining and culture on liquid media (BACTEC MGIT 960; Becton Dickinson, Sparks, MD). Performance status, chest radiographs, and anthropometric measures were assessed at baseline and again at 8 wk.

RESULTS

The participants (n = 154) were randomly assigned to the micronutrient (n = 77) or placebo (n = 77) group. Twenty participants were HIV infected (13%), and 12 participants had an unknown HIV status (8%). No differences in time to smear or culture conversion were observed between the treatment groups by Kaplan-Meier analysis (P = 0.15 and P = 0.38, respectively; log-rank test). Log-logistic regression analysis found no significant group interaction effect in time to culture detection over the 8-wk period (P = 0.32). No significant differences in weight gain (2.3 ± 3.5 compared with 2.2 ± 2.4 kg, P = 0.68) or radiologic resolution were observed between the treatment groups.

CONCLUSION

Supplementation with vitamin A and zinc did not affect treatment outcomes in participants with pulmonary tuberculosis at 8 wk. This trial was registered at controlled-trials.com as ISRCTN80852505.