Research on the merits of a fizzy drink tax comes after Mayor Michael Bloomberg infamously planned to limit sales of sugary soft drinks in New York to 16 ounces (454 grams) per cup.
Although New York City’s Board of Health approved the move in September 2012, by March the New York Supreme Court blocked the proposal from becoming law.
It was argued that the plan had too many loopholes and violated the jurisdiction of the City Council. Bloomberg appealed the decision.
Some 34 US states and the District of Columbia have food taxes that affect sugar-sweetened drinks. According to the World Health Organisation, Mexico has the highest obesity rate of any major country after Egypt.
Health experts who have called for a 20% tax on sugary soft drinks say the move could raise more than £275 million each year for the treasury - around 8 pence per person, per week.
This saving "could be used to increase NHS funding during a period of budget restrictions or to subsidise foods with health benefits, such as fruit and vegetables," researchers from Oxford and Reading universities said.
Calls for a 20% tax hike on fizzy drinks have been met with skepticism by Cambridge University clinical biochemistry and medicine professor Sir Stephen O'Rahilly.
Whilst any effective discouragement to the ingestion of sugary beverages would likely have a health benefit on society, taxation of specific foods is likely to be currently politically undeliverable in most democracies.
A workable alternative might be to encourage the major companies to switch to the aggressive promotion and marketing of less harmful versions of their products.
Doctors who have called on the Government to introduce a 20% tax on sugary drinks say 16 to 29-year-olds consume the most sugary drinks - an average of 300ml per day, compared to 60ml among those aged over 50.
Younger adults and children consume much greater quantities of sugary drinks.
This is a concern for their health, not only in terms of diabetes and obesity, but also tooth decay.
Our work suggests that a sugary drinks tax would have a much greater impact in terms of reducing obesity in younger adults.
A 20% tax on sugary drinks would cut the number of overweight people in the UK by 285,000 over 10 years, according to experts from Oxford and Reading universities.
A tax on the drinks, which the researchers say are linked to "ill health" and have "no beneficial nutrients", could reduce cut the number of people who are obese by 180,000 alone, according to the findings printed in British Medical Journal .