Stevia-sweetened fizzy drink Pepsi Next will hit our shelves next week, a month ahead of rival Coke Life - but health experts doubt the new products will bring any major reduction to the overall harm caused to Kiwis by sugary drinks.
Pepsi Next, which like Coca-Cola's green-labelled product is sweetened with stevia leaf, is being marketed as a healthier alternative to regular Pepsi Cola, which contains about 30 per cent more sugar.
Stevia comes from a plant native to South America and had been used as a natural sweetener around the world for hundreds of years before the rival soft drink giants saw it as a way to slash sugar levels.
It had been growing in popularity because of its ability to naturally reduce sugars in diets while retaining a high level of sweetness, said Aisha Daji Punga, commercial director of PepsiCo's New Zealand bottling partner, Frucor.
Coca-Cola's own product, expected to launch here in early April, was developed in response to a growing demand for less sugary drinks.
Professor Tony Blakely of Otago University's Department of Public Health said part of the drive to stevia was fuelled by public concerns about aspartamate as an artificial sweetener.
While it was "feared" to be a carcinogenic, there was no strong evidence of harm from aspartamate.
"Nevertheless, this view among society and the fact that stevia is natural have driven the soft drink countries to use stevia," he said.
"In part at least, the companies should be applauded for providing the consumer with non-sugary options."
Consumers wanting the healthiest choice, he said, could still find it flowing from their kitchen tap or office water cooler. Water prevented oral health damage that still came with diet fizzy drinks
"Without doubt, sugary drinks are bad for obesity, bad for diabetes, bad for oral health, and probably bad for heart disease. Swapping to diet drinks will avoid nearly all of this harm - but not all of it. Swapping to water would, therefore, be best."
University of Auckland nutrition and global health professor Boyd Swinburn saw the new products as "a step in the right direction" but said there would be more impact from excise taxes on sugary drinks, removing the products from schools and changing their profile in social marketing.