In a new report entitled “Fiscal policies for diet and the prevention of non-communicable diseases,” the World Health Organization (WHO) recommends taxing drinks high in sugar content to address growing rates of obesity and non-communicable diseases like diabetes across age groups.

“There is reasonable and increasing evidence that appropriately designed taxes on sugar-sweetened beverages would result in proportional reductions in consumption, especially if aimed at raising the retail price by 20% or more,” the report reads.

New Yorkers may remember when former mayor Michael Bloomberg attempted to limit sugary drinks in New York City. The proposed law would have banned the sale of many sweetened drinks over 16 ounces.   but was struck down the following year by the state’s highest court on the grounds that the NYC Board of Health had exceeded its authority.

But Bloomberg, who left office in 2013, has become instrumental in helping the government of Mexico, one of the world’s largest consumers of soda, to reduce consumption. In partnership with civic groups in Mexico, Bloomberg’s charitable foundation overcame heavy industry opposition, and in 2014 Mexico’s President, Enrique Peña Nieto, signed a soda tax into law.

Was the soda tax effective? Depends who you ask. A quick look at the variety of headlines reveals some discrepancy in how the tax was perceived: “Mexico’s Soda Tax Success” from Bloomberg View, obviously an interested party; “Is Mexico’s Soda Tax Really Working?” from Reason, a libertarian magazine; “Soda Sales in Mexico Rise Despite Tax” from The Wall Street Journal, and “Mexico’s Sugary Drink Tax Makes A Dent In Consumption, Study Claims” from National Public Radio.

Quoted in a different WHO publication, Dr. Juan Rivera Dommarco, who co-authored a study of the tax’s effectiveness in BMJ, says “taxing sugar-sweetened beverages has a legitimate place as part of a toolkit for the prevention of obesity. Taxation alone will not solve the problem, but can contribute to its prevention and control.” As with other public health issues, e.g. climate change, before trusting a claim, look for the supporting scientific research.