A 10PC sugar tax on fizzy drinks has the potential to reduce the number of overweight and obese adults by 24,000.
The major unpublished report, a copy of which has been obtained by the Irish Independent, was commissioned by Health Minister James Reilly and a team of experts, to provide objective evidence of the need for the sugar tax to be introduced in the Budget to help curb the obesity timebomb.
But despite the strong case for the tax, the proposal was shot down by Finance Minister Michael Noonan and his officials, who claimed fizzy drinks were already subject to a high enough levy of 23pc VAT.
The report's findings led to a majority of members of the department's Special Action Group on Obesity – made up of a range of external experts and officials – to recommend the sugar tax be imposed.
Minutes of their crunch meeting in November show it was attended by Dr Reilly, who asked for a detailed submission.
The report, carried out by the Institute of Public Health, included a modelling analysis by academic Dr Mike Rayner of Oxford University, who assessed the impact of a 10pc tax.
His team estimated that it could reduce the number of obese adults by 10,000 and overweight people by 14,000.
There would be a significant reduction in calorie intake in the 18-24 age group. Overall, the tax could potentially lead to a 1.25pc reduction in obesity.
Dr Rayner said while the measure had significant potential, he could not be sure that people would not switch to other calorific drinks such as fruit juices.
The 157-page report showed:
• We are individually downing 83 litres of fizzy drinks a year.
• More than one in three adults is overweight and one in four is obese.
• 15pc of two- to four-year-olds are overweight and 3pc are obese.
• Teenage boys drink the most fizzy drinks.
• Being overweight and obese increases the risks of diabetes, high blood pressure, heart disease, cancer, liver and gall bladder disease.
An IPSOS MRBI poll of public opinion found four in 10 would switch to diet drinks if they were cheaper and 60pc said they would drink water if they consumed fewer fizzy drinks.
The Special Action Group on Obesity said they acknowledged that one single initiative would not solve the obesity problem, but all measures that lead to positive changes in behaviour should be encouraged.