A new study by Otago University and Pacific-based researchers shows about three quarters of Pacific nations have implemented taxes on sugar-laden products.
More than a third of them have increased these taxes by at least 20 percent in the past two decades.
University of Otago senior research fellow doctor Andrea Teng said Tonga is leading the way.
"Our research has shown that that tax has been effective at reducing imports of sugary drinks and after each of the tax increases there was a reduction in imports, and the other thing it was shown there was the increase of production bottled water. So signs that people substituting away from sugary drinks to more healthier options."
Teng said taxes are an effective tool to combat diet-related chronic diseases like obesity and type-two diabetes.
And Pacific nations are leading the way with taxes on sugary drinks in a bid to battle unhealthy obesity.
Teng said sugar taxes are a powerful way to combat diet-related chronic diseases
"Sugary drinks tax are a really important tool in terms of addressing obesity, diabetes, oral health, basically in the Pacific there is a NCD crisis'.... So this is a really important tool for poor countries in addressing obesity related disease."
Teng said many of these taxes still need to be strengthened and more Pacific countries should adopt them.