One of the biggest challenges facing soft drinks producers in the US is the looming spectre of a tax on sugary drinks in some states and cities.

The industry, under fire from critics who say it has played a large part in the nation's obesity problem, agreed to voluntary guidelines in 2006 pledging to replace full-sugar drinks in school vending machines and canteens with healthier alternatives.

Soft drinks producers have already made great strides to reduce the amount of full-sugar drinks they sell, with consulting firm Keybridge Research reporting that the total beverage calories shipped to schools between the first half of the 2004-2005 school year and the current school year (2009-2010) has fallen 88%.

But these efforts could be a case of "too little, too late". The state of California and the city of Philadelphia have introduced legislation to tax soft drinks, with New York City and potentially New York State set to follow suit and others weighing up similar moves.

So what are the chances of such a tax being imposed in the UK? The jury is still out. The FSA has already asked manufacturers of high-sugar soft drinks to make a voluntary 4% reduction in added sugar levels by 2012. The FSA has also recommended that individual cans should be reduced in size from 330ml to 250ml by 2015, to reduce calorie intake a proposal the industry has decried as expensive and unworkable.

Calypso sales and marketing director Richard Cooke believes that the bigger debate in the UK looks set to be about sugar versus artificial sweeteners.

"Sugar is a natural sweetener and people want natural ingredients not artificial sweetener."

Focus On Soft Drinks