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Health-Centred Policy Design: Are Sugar Taxes Effective?

- Professor Karen Hofman

Wits Researcher and Founding Director of PRICELESS SA, Professor Karen Hofman was invited to speak at Princeton University’s Princeton Pulse Podcast to discuss the efficiency of imposing a sugar tax for sweetened beverages. The discussion compared notes of the experiences of South Africa to those of the United States of America (USA) - State of Philadelphia.

Diabetes is one of the fastest-growing diseases globally and has seen an increase in the number of people living with this chronic disease rising from 108 million in 1980 to 422 million in 2014. In South Africa, diabetes has a high mortality rate with roughly 4, 2 million people of the population living with the condition. Whilst in the USA, the State of Philadelphia in particular has the highest prevalence of diabetes, with approximately 15.4% of all persons over 18 affected.

The World Health Organisation has attributed the prevalence of diabetes to low and middle-income countries as opposed to high-income countries. Despite this, the disease is also on a  rise in high-income countries such as the USA, particularly for people with comorbidities like cardiovascular disease, chronic kidney disease, pneumonia, tuberculosis (TB) and others.

“While South Africa is still the epicentre of the HIV epidemic, it is now overtaken by diabetes and heart diseases,” says Professor Hofman.

The drastic increase in the number of cases of blindness, kidney failure, heart attacks, stroke and lower limb amputations is also on a rise in low and middle-income countries. Professor Hofman shared that South African hospital wards are treating more diabetes patients who are more likely to have their limbs amputated before succumbing to the disease. She adds that even more concerning was the susceptibility of fatal COVID-19 infections to patients with underlying comorbidities, especially among the younger population.  

In South Africa, calls by health and civil society organisations for the government to implement policies that would encourage the population to adopt a health-conscious lifestyle pre-dates the COVID-19 pandemic. However, it’s the pandemic that highlighted the extent to which diseases like diabetes and TB pose a serious health risk to South Africans and a burden to the country’s health system. 

The SAMRC/Wits Centre for Health Economics and Decision Science Research Unit (PRICELESS SA) advocated for the “Taxation of Sugar-Sweetened Beverages” policy (also known as the Health Promotion Levy) in South Africa which the government implemented in April 2018. Since then, other countries have also followed suit.

The sugar tax policies in both South Africa and Philadelphia, are used as a corrective tool to address soaring figures of obesity and other non-communicable diseases. Professor Hofman says that more front food labelling is essential as it makes nutritional information easier to locate, especially for low-literacy individuals. She says that in so doing, this information will also assist parents with making informed choices when purchasing children’s food as obesity numbers in children are growing at an alarming rate globally.

Also adding to the risk of children living with diabetes is the “deliberate and relentless marketing” of sugary products to the sub-Saharan population as a target growth market by multinational corporations. Professor Hofman noted that such efforts by corporations distinctly target “the poor”, which has translated to the rise of diabetic people living in sub-Saharan Africa. This supports the notion that high sugar intake has a ripple effect on social and economic costs in low and middle-income countries particularly relating to healthcare and social services.

Professor Hofman compared experiences with her fellow guest on the podcast, Dwayne Wharton, who is an advocate for health fairness and supported Philadelphia's beverage tax policies. The discussion juxtaposed their learnings in policy design and highlighted related equality issues. They both cited the importance that research played in developing these policies in both contexts.

Professor Hofman says their research found that the sugar tax is effective in reducing consumers’ appetite for sugary beverages. She says that before the application of the sugar tax, teenagers in Soweto would drink an average of ten cans of frizzy drinks a week. However, since the implementation of the Taxation of Sugar-Sweetened Beverages, this has since been reduced to four cans a week.

“The amount of sugar by volume came down as well as the amount of volume of the actual product (the liquids)” adds Professor Hofman.

Further to the reduction of the sales of sugary drinks, she adds that bottled water has seen an increase in sales as a healthier and cheaper alternative. Although it is too soon to quantify the reduction of obesity as a direct result of the sugar tax implementation, Professor Hofman says their mathematical modelling predicts that a 20% sugar tax rate would decrease obesity by approximately 250 000 people per year.

Although this health campaign has yielded positive results, the biggest threat to its further success is the pushback and political interference in the favour of multinational corporations. Although many such corporations have vowed to not market and sell their products at schools to alleviate diabetes in children, the “pledge” approach taken for this process means that corporations are not obliged to comply. This continues to be a setback in combating the upward trend of a diabetic nation.

Read more of Professor Hofman's research work on this topic ( )

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