As governments struggle to address the rising prevalence of obesity and other chronic diseases there have been increasing calls for taxation on selected foods as a means of improving the quality of national diets. Last year Denmark introduced the world’s first ‘fat tax’, but in an abrupt turnaround the much maligned tax has been repealed. What went wrong?
Targeted taxation of foods
The rationale for targeted taxation of foods to improve health draws on the fundamental economic principle that the demand for any good is related to its price. If the price goes up, the demand goes down, and vice versa. Hence the demand for goods is said to be ‘elastic’. Viewed through this prism, addressing diet-related chronic disease becomes straightforward – use the tax system to increase the price of junk foods and lower the price of healthier foods. Too easy.
Following the failure of the ‘eat less fat’ strategy for addressing the obesity epidemic the focus has shifted to sugar-sweetened beverages. Will this approach be more fruitful? Is sugar the problem, or is it liquid calories? Or are we missing something obvious?
Two new studies recently published in the New England Journal of Medicine have shed further light on the issue of soft drinks and weight gain.
Two new soft drink studies
Ebbeling and colleagues studied 224 overweight and obese adolescents who regularly consumed sugar-sweetened soft drinks. Half the subjects participated in a 1-year program designed to decrease consumption of these beverages. Both this intervention group and a control group were followed up for a further year after the intervention was complete. After one year the mean body weight of those in the intervention group was significantly lower (1.9kg) than that of the control group, though significance was lost at two years. So the program worked while underway but its effects did not persist.