An experiment in Mexico had promising results.
An experimental price hike in Mexico, which added an 8 percent tax on high-calorie junk food, has proven successful according to a new study. Researchers at Mexico's National Institute of Public Health and the University of North Carolina, Chapel Hill analyzed how the higher prices influenced the buying decisions of families from a variety of economic levels.
The results, published in the PLOS-Medicine journal, showed that while the effect was not dramatic, it was signficant. Researchers found that following implementation of the tax in 2014, junk food purchases dropped by 5.1 percent, The New York Times reports. Perhaps most telling was the differences in the average reduction in purchases between low, medium, and high-income households. Those in the poorer group of households bought 10.2 percent less junk food after the tax was put into place, whereas medium-income families reduced their purchases by 5.8 percent. The tax did not appear to effect the spending purchases of the high-income households.
Though the economic data speaks for itself, many parts of the dietary puzzle were not analyzed or factored into the study results. The tax—which was implemented on processed foods with more than 275 calories per 100 grams—reduced junk food purchases, but there is no information on whether calorie intake went down among the families, or if they ended up making healthier food choices overall. While the researchers note that further studies would be beneficial in analyzing the benefit of the tax, they say future research "should explore how these shifts are linked to changes in the nutritional quality of the overall diet."
"At the moment, Mexico lacks a broader policy on eating well... there are just emergency measures to limit damage," says Julieta Ponce, a nutritionist at the Center for Dietary Orientation.