Sugar-sweetened beverages and household sugar consumption patterns among adults living in Southgate, Phoenix

Abstract

Background: The Health Promotion Levy (HPL) was implemented in South Africa in 2018 as an intervention to decrease sugar consumption. While the link between excessive sugar consumption and dietary risk factors is well established, there is limited conclusive evidence that fiscal policy measures like the HPL can reduce sugar consumption and lead to favourable health outcomes. Aim: To determine the current sugar-sweetened beverage (SSB) and household sugar consumption patterns among adults in the Southgate Phoenix area. Methods: This study adopted both desktop and quantitative methods through a cross-sectional study. The desktop study included a scoping review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The aim of the scoping review was to investigate the implementation of the sugar tax by various countries and assess the effectiveness thereof. Data from a syndicated Euromonitor generated report on sales of SSBs in South Africa were reviewed. Using a validated questionnaire, quantitative methods were also used to gather data on the current SSBs and household sugar consumption patterns among 399 consenting adults living in the Southgate Phoenix area. Sugar threshold detection test (TDT) of different sugar solutions and sweetness preference of market samples of cola SSBs were determined through sensory evaluation among 98 consenting adults living in the Southgate Phoenix area. Results: The scoping review included 37 studies on sugar tax in 17 countries. Most studies, 37.8% (n= 14), were conducted in various United States of America (US) states, followed by Mexico (16.2% n= 6) and South Africa (10.8% n= 4). Just over half of the studies (51.4% n= 19) reported a reduction in sales volume of SSBs. A decrease in SSB consumption was reported by 37.8% (n= 14) studies, whilst 2.7% (n= 1) study reported both reduced sales and consumption of SSBs. Reduced body mass index/weight was reported in 8.1% (n= 3) of studies. Key results for the household sugar and SSB consumption showed that a significant 55.1% (n= 220) of households purchased brown sugar, p<0.001, while 44.9% (n= 179) purchased white sugar. A significant 92.0% (n= 367) of households purchased sugar monthly p<0.001. Households (65.5% n= 102) predominantly purchased sugar in 2kg packs, p<0.001. There was a significant correlation between income and purchasing frequency and the size of sugar packaging purchased by participants; those with higher income purchased sugar less frequently (rho= .187, p<0.001) and in smaller packaging (rho= -.145, p= .006). A significant 96% (n= 382) of participants used sugar in tea and coffee, p<0.001, while 58% (n= 230) added it to cereal. A significant 68.1% of the participants reported using either 1 or 2 teaspoons of sugar in their tea/coffee, χ2 (4) = 153.619, p<0.001. However, 32.9% (n= 131), 16.5% (n= 51) and 2.5% (n= 10) consumed three teaspoons, four teaspoons and more than four teaspoons in their tea and coffee, respectively. The Mann-Whitney test analysis showed that males added significantly more sugar in their tea/coffee than females, Z= -2.779, p=.005. The amount of sugar added to tea/coffee was negatively correlated with age, rho= -.186, p<0.001. Results also indicated that the consumption of tea or coffee with sugar was positively correlated with age (rho=.175, p<0.001), with older people consuming more servings of sugar-sweetened tea/coffee. Regarding the consumption of SSBs, a substantial 77% (n= 308) of participants indicated that they frequently consumed sugar-sweetened carbonated soft drinks. Flavoured water was the second most consumed category, with 32% (n= 129), followed by energy drinks at 24% (n= 96). The Pearson’s chi-square analysis indicated that significantly more females consumed flavoured teas than males, χ2 (1) = 5.568, p=.018. Furthermore, the Pearson’s chi-square analysis indicated that significantly more females consumed flavoured water than males, χ2 (1) = 12.983, p<.001. A significant 76% (n= 305) of participants reported consuming SSBs at home, p<0.001. The proportion of SSBs purchased positively correlated with age (rho=.150, p=.003), with older people being associated with buying larger sizes of SSBs. Results from the Pearson’s chi-square test showed that a notable proportion of 18-25-year-olds were unaware of the sugar tax, while a notable proportion of 26-35-year-olds were aware of this tax, χ2 (4) = 13.924, p= .008. For the preference test, 40.8% (n= 40) participants preferred Coo-ee and noted that it was the sweetest SSB, followed by Coke at 27.6% (n= 27), χ2 (3) = 19.653, p<.001. Results for TDT found that a significant 57.1% (n= 56) of participants preferred the yellow-dot-30g/1ltr sugar sample (p<.001); the reason given by a significant percentage of 62.2% (n= 61) for their selection was sweetness preference (p<0.001). A significant 48.4% (n= 16) preferred the orange-dot-0.3g/ltr sample the least (p= .001). This indicates that the sample population has a preference for higher rather than lower levels of sweetness in their SSBs. Conclusion: South Africa was the first African country to implement the sugar tax, so it is important to document the barriers, challenges, and other findings from inception. In this study, we found that sugar tax studies were mostly conducted in first-world countries, and emerging literature is available on the South African context. While the SSB industry has been regulated, its resulting impact on the consumption of SSBs and household sugar consumption remains an underexplored research area. Households also lack information pertaining to optimal sugar intake and the long-term health implications of exceeding such limits. Joint efforts with multiple initiatives and interventions could yield better results in combating obesity and reducing the burden of non-communicable diseases (NCDs). These initiatives should include nutrition education and HPL awareness campaigns, as well as current fiscal policies.