By CBS3 Staff

PHILADELPHIA (CBS) – A new study from Drexel University found the soda tax has had very little effect on what Philadelphia residents are drinking. The study, which was published in the International Journal of Environmental Research and Public Health, found Philadelphians are only drinking three less sugary beverages a month since the 1.5-cents-per-ounce tax was implemented a year ago.

Researchers surveyed 515 random adults in the Philadelphia region and neighboring cities, including Camden, Trenton, and Wilmington.

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Residents shared how much and how frequently they drank soda, fruit drinks, energy drinks and bottled water during a 30-day period when the tax was first implemented in December 2016-January 2017, and again a year later during December 2017-February 2018.

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According to the survey, 39% of Philadelphians and 34% of those in surrounding cities, reported drinking fewer sugar-sweetened beverages.

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“The availability of untaxed sugary beverages outside of Philadelphia, the still relatively lower price of these drinks compared to healthier ones and marketing and advertising may explain the low effect of the tax,” said lead author Yichen Zhong, a doctoral student at the Dornsife School of Public Health.