New Zealand researchers argue that subsidizing fruits and vegetables while taxing fattening foods and soft drinks could decrease rates of chronic disease.

Defiantly sipping a mega-jug of Coca-Cola, comedian Jon Stewart lambasted New York City mayor Mike Bloomberg’s latest attempt to curb the amount of sugar his constituents consume. “I love this idea you have of banning sodas larger than 16 ounces,” Stewart joked. “It combines the draconian government overreach people love with the probable lack of results they expect.”

Bloomberg’s ban may not sit well on New Yorkers’ stomachs, but researchers from the University of Auckland and the University of Otago in New Zealand present evidence in this week’s PLoS Medicine that government does have a role to play in regulating consumption. They argue that subsidizing “good” foods and taxing “bad” ones could lead people to choose healthier items, especially consumers in lower income brackets.

Americans eat an incredible 22 teaspoons of sugar per day, or 17 four-pound bags of sugar per year. Combined with saturated fats and trans-fats in fast food and other fried fare, rates of preventable disease have soared. According to the Centers for Disease Control and Prevention (CDC), the incidence of diabetes in the U.S. rose 176 percent between 1980 and 2010.

“Dietary intakes of saturated fat and sodium, in particular, are higher than national recommendations, and intakes of fruit and vegetables are lower. These sub-optimal dietary intakes are major risk factors for non-communicable diseases (NCDs) including diabetes, heart disease, and several types of cancer,” says Dr. Helen Eyles, lead study author and Public Health Nutritionist at the National Institute for Health Innovation at the University of Auckland. “NCDs have overtaken infectious diseases as the greatest cause of early death in many countries, including the U.S. If we can make small improvements to dietary intakes across populations, we can produce large improvements to population health.”

Eyles and her research team analyzed the results of 32 studies from high-income countries concerning food pricing strategies, food consumption, and the prevalence of chronic diseases, such as diabetes and heart disease.

According to their analysis, based on data aggregated from the source studies, governments could see a 0.02 percent decrease in saturated fat intake for every one percent increase in price, as well as a one to 24 percent decrease in soft drink consumption with a 10 percent rise in price.

Conversely, they determined that a 10 percent price decrease for fruits and vegetables could increase consumption by two to eight percent, though it’s possible that consumers would buy unhealthy foods with their financial savings.

Importantly, Eyles and her team also found that this model of taxes and subsidies disproportionately benefits poor individuals, thus decreasing some health inequalities. It makes sense; fast food and candy are cheap, but fresh fruits and vegetables are not. Bringing down the price of healthy fare would make it more accessible for low-income households, and better able to compete with the likes of Mickey D’s.

“Whilst taxes on food may hit poorer people harder than richer people, the positive impact on health is likely to be relatively greater for low-income groups,” Eyles says. “This is because poorer people are generally more price-sensitive and thus more likely to make changes to their food purchases and diets in response to taxes and subsidies. However, to avoid an overall detrimental financial impact on low-income families and worsening food insecurity, a mixture of subsidies and taxes may be required.”

It remains to be seen whether the public—not to mention powerful food and drink lobbyists in Washington—will accept taxes on fatty foods and soft drinks. Eyles says that she’s provided the scientific evidence for policy change, but that it’s up to legislators to debate the specifics of implementation.

Few would argue that the way most Americans eat is healthy, but mustering the political will to change that, even with something as straightforward as a tax on foods known to contribute to disease, may be an uphill fight. It is certainly one worth having.

Eyles’ team aggregated data from 32 quantitative studies on food pricing strategies and consumption patterns published in English between January of 1990 and October of 2011.

For full citations of the studies included in this analysis, see the “References” list at the end of the published article, available here from PLoS Medicine.