Sugar tax cuts sugary drinks sales by 12% in Mexico

By Sally Robertson, B.Sc.Jan 7 2016

A 10% tax on sugar-sweetened drinks in Mexico has been associated with a 12% cut in sales just one year after its implementation, according to a study published in The BMJ. The sugar tax was also associated with a 4% increase in the purchase of untaxed beverages.

The authors of the paper say the findings have important implications in terms of policy and decision making.

Mexico introduced the tax on sugar-sweetened drinks in January 2014 in a bid to reverse what are some of the highest levels of diabetes, overweight and obesity in the world.

M Arantxa Colchero (Instituto Nacional de Salud Pública, Morelos, Mexico) and colleagues examined nationally representative data from more than 6,200 Mexican households across 53 cities during the first year since the tax was implemented. They compared the predicted amount of taxed and untaxed beverages purchased during this post-tax period with estimates of purchases without the tax, based on pre-tax trends.

After adjustment for factors such as age, gender, socioeconomic status, employment and salaries, the analysis showed that the purchase of taxed beverages fell over time, reaching a decline of 12% compared with untaxed purchases, by December 2014.

This translates as a reduction of 4.2 liters in the amount of taxed beverages being purchased by the average urban Mexican during 2014.

By contrast, the sale of untaxed drinks rose by 4%, which translates as an increase of 12.5 liters being bought by the average urban Mexican over the course of 2014. This was mainly driven by an increase in the sales of plain bottled water.

Although the purchase of sugar-sweetened drinks was significantly reduced across all socioeconomic groups (low, middle and high), the greatest reduction was seen among the poorest households, where purchases fell by 17%, compared with pre-tax trends.

Colchero and team say the short term change is “moderate but important” and that “continued monitoring is needed to understand purchases longer term, potential substitutions, and health implications.”

Back in the UK, Public Heath England has said that a sugar tax of between 10% to 20% combined with other measures such as clamping down on the advertising of junk food, would be an effective way of combating obesity. The statement follows the findings of a study published in The Lancet Diabetes & Endocrinology, which showed that a 40% cut in the sugar content of sugar -sweetened drinks in the UK over the course of five years could prevent as many as 500,000 cases of overweight, 1 million cases of obesity and 300,000 cases of type 2 diabetes, over two decades.

The authors of that study say that their proposed strategy “provides an innovative and practical way to gradually reduce energy intake from sugar-sweetened beverages and its combination with other strategies, including a tax on sugar-sweetened beverages, would produce a more powerful effect.”