Criticising the proposed anti-obesity policy involving a levy of 10% tax on sweetened soft drinks, nutritionist Prof Jack Winkler suggests an alternative that might have a more positive impact on the increasing obesity problems in the UK.

In response to a report published in the British Journal of Nutrition, Prof Winkler says the authorities should consider abolishing the 'pricing parity' between sugared and sugar-free soft drinks.

In defence of his proposal, the expert refers to one of the basic laws of economics that deal with the elasticity principle of demand. According to the initial research that suggested the tax, a 10% hike in the price of sugar-sweetened beverages might lower the consumption by 7.5ml per person every day. But Jack Winkler in his remark says the proposed tax is unlikely to cut the demand of soft drinks by much.

"In plain English, 7.5ml is 0.4% of the most popular two-litre bottle, less than a sip. It would not even cut sugar intake by a gram, only 12.6kj (3kcal)," the expert says in his commentary, implying that the decision of taxing sweetened beverages may not prove beneficial as far as obesity treatment is concerned.

On the other hand, putting an end to parity pricing between sugared and sugar-free soft drinks could produce positive results in terms of consumer preference, the nutritionist notes, explaining that there is a huge potential for easing the weight problems if companies think about selling off sugar-free products at a much cheaper rate.