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A Sugar Tax Is Not Enough

There must also be a clear national dialogue on what healthy balanced diet looks like

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


From Mexico to the United Kingdom, governments use taxation to influence social behavior, including curbing sugar consumption. South Africa is the latest country using taxes on sugary beverages to try to reduce citizen’s intake of the drink. In September, the South African Treasury deputy director general announced in Parliament that the long-discussed and debated tax on sugary drinks will go into effect in 2018. While initially there was some resistance, a new study shows a 16 percent increase in support for the measure.

South Africa—like the broader world—is at a critical health juncture. Lifestyle diseases such as diabetes, obesity and related ailments are rising and must be addressed. Last year, new research suggested that the true effects of sugar have been kept hidden from the general public and are just now coming forward. While debates are still ongoing, many nutrition experts say excess sugar is a primary cause of obesity and heart disease. In the African context, an increase in non-communicable diseases like heart disease is eroding gains made in the fight against AIDS, tuberculosis and malaria. 

Notably, some Africans enjoying the benefits of increased income fall into the trap of processed and convenient foods thus altering the long term benefits of their change in socioeconomic status. The increased income can be associated with weight gain and diet-related non-communicable diseases such as diabetes. The cost of inaction has consequences on growth and development plans. WHO estimates that more than 10 million children under 5 years old were overweight or obese in 2015.


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While a tax is not the only way to reduce these diseases, it still can help improve citizens’ health. Research shows that taxes on sugary drinks can lower consumption and reduce obesity and Type 2 diabetes. A study looking at the possible effects of the sugar tax in South Africa demonstrated the likelihood that consumers will switch to other drinks. In Mexico, a report showed that in the second year of a tax of 10 percent per litre on all sugar-sweetened drinks, there has been a 10 percent decrease in purchases of taxed drinks and a 13 percent increase in plain water purchases. Thus, despite the prevalence of sugar in not only beverages but processed foods of all kinds, it is possible to change the tide in public consumption.

The downside is, it may not be a permanent shift. Newer information from Mexico shows that after a brief period of drop in sales volume, volume is rising again and appears to be normalising. This suggests that taxes may have a limited impact because a tax only affects the affordability of the drinks without affecting its availability, the acceptability of drinking it and awareness about the negative health outcomes.

Thus, taxation, as proposed, is a potentially positive step, but without a clear national dialogue on healthy balanced diet that includes more fresh, healthy local foods, we are missing an opportunity to change a habit that is silently killing the productive forces of the African continent. By 2030, non-communicable diseases will be the most common cause of death, we need not wait for AIDS-related deaths numbers to act.

Policymakers across the continent, particularly in the Ministries of Finance and Planning, should be alarmed. Africa needs an able workforce to keep economic transformation on track. Coordination with Ministries of Planning and Finance, Agriculture, the private sector and with the World Health Organization and the Africa Centers for Disease Control is critical.

Private Sector companies operating in Africa employ the majority of the Africa’s middle class and can have a role. Leaders of these institutions can ensure that canteens offer an alternative to limit the health bill (limited access to unhealthy options) while inducing change among employees. There should also be more efforts to reduce the availability of sugary products in schools and workplace, retail environments and the general food supply.

Of course, there is also an individual responsibility to limit consumption as the habits of adults and children are not formed in the workplace or schools. There is a joint responsibility, as community members, to increase the level of acceptability of fruits, vegetables and local foods relative to sugary alternatives and make water the primary source of our liquid intake. Further, while it is impossible to regulate one’s taste buds, it is possible to invest heavily and consistently in the consequences of the choices that we make. Parents, too, have a responsibility to nudge their children into healthy habits.

In order to realise the potential of the African continent with my generation, we ought to challenge our individual choices and their consequences for society at large. African needs healthier and educated generations to capitalise on the health gains by transforming Africa. We can nudge people by taxes, and indeed, real change will come from our ability to implement policies that weigh the health bill against current changes in consumption that deteriorates the ability of Africans to transform their continent.