When it comes to the proposed tax on sugar-sweetened beverages, researchers warn consumers to be cautious about misinformation campaigns that could be taking a page out of the tobacco lobby’s playbook.
A sugar tax of at least 20% could prevent about 160 000 new cases of type 2 diabetes in South Africa over the next 20 years, according to a 2015 mathematical model published in the journal PLOS ONE, an international peer-reviewed journal, which lends it significant credibility.
“Evidence from around the world shows that having a tax on sugar-sweetened beverages of at least 20% is one of the best things that you can do as part of a series of steps to deal with obesity,” says researcher Karen Hofman, the head of Priority Cost-Effective Lessons for Systems Strengthening (Priceless SA) based at the University of the Witwatersrand’s School of Public Health.
A 2013 study published in the British Medical Journal reviewed existing evidence on sugar and weight gain. The meta-analysis of more than 60 studies found consistent evidence that decreasing sugar intake led to weight loss. This review also confirmed links between children’s intake of sugar-sweetened beverages and their risk of becoming overweight.
Countries such as France, Brazil and Norway have instituted sugar taxes. A 2015 study by the University of North Carolina in the United States and Mexico’s national health institute found that the introduction of a sugar tax in 2013 led to an average 9% reduction in household purchases of taxed, sugar-sweetened beverages. Published in the British Medical Journal, the study also found that family purchases of untaxed drinks went up by about 4%, driven largely by increased purchases of bottled water.
Earlier this year, Finance Minister Pravin Gordhan announced the government’s decision to introduce a tax on sugar-sweetened beverages to reduce excessive sugar intake.
Hofman and others developed the mathematical model to demonstrate the public health gains of such a tax, which ultimately informed the government’s decision.
This week, the Institute of Race Relations became the latest organisation to attempt to discredit research showing that taxing sugary drinks could save lives in South Africa. Hofman cautions that attacks on the public health rationale behind the tax may be similar to ploys that health activists, particularly anti-tobacco campaigners, have seen before.
The institute questioned the rationale behind the proposed tax, arguing that it would only be a burden on the poor and would not reduce obesity.
“There is no direct evidence that a reduced consumption of sugar-sweetened beverages translates into reduced energy intake. There’s just no way of pinpointing the extent to which the sugar-sweetened beverages tax has had any impact on weight at all,” says the institute’s head of policy research, Anthea Jeffery.
According to Jeffery, Hofman’s mathematical model, “has no hard data or credible evidence to substantiate its conclusions”.
Same old tricks?
Hofman has hit back, saying that the tobacco lobby spent years trying to discredit scientific research that revealed the dangers of smoking.
“This is a strategy from the tobacco playbook, in which they [the industry] tried to discredit peer-reviewed scientific research.
“South Africans are the eighth-highest sugar consumers globally. Such a tax will cut the consumption of sugary drinks, just as regulation cut tobacco use,” says Hofman.
Continued attacks on the proposed sugar tax come on the heels of new research that has unearthed documents suggesting the US sugar lobby paid to create data in the 1960s and 1970s that would cast doubt about the hazards of sugar.
Published last week in the Journal of the American Medical Association Internal Medicine, the study says more than two dozen documents point to an attempt by the industry to downplay sugar consumption’s links to coronary heart disease.
Subsequent research, including a 2013 study in the American Heart Association Journal, found that sugar-sweetened beverages were a major cause of preventable deaths from illnesses such as diabetes and cardiovascular disease. The World Health Organisation now says that increased sugar consumption, “particularly in the form of sugar-sweetened beverages, is associated with weight gain in both children and adults”.
The Journal of the American Medical Association Internal Medicine study suggests that the negative effect of this kind of industry-sponsored research could be long-lasting. It notes that, even today, as policymakers globally debate sugar control policies, coronary heart disease is not always cited as a consequence of high sugar intake. Researchers recommend that policymakers should consider giving less weight to food industry-funded studies.
Meanwhile, a 2015 study in the journal Public Health Nutrition estimates that an annual 2.4% growth in sugar beverage sales, along with population growth and ageing, will result in more than 1.2-million additional obese adults in South Africa by 2017. Sugary beverage consumption is estimated to be responsible for more than one-fifth of these obesity cases, says the study.
Hofman warns: “The cost of lifestyle-related conditions for medical aid schemes and the government health system is rising by the day. So is the cost of not acting as quickly as possible.”