A tax on sugary drinks could prevent 3.7m obesity cases by 2025, according to Cancer Research UK and the UK Health Forum.
The research worked out the likely impact of the tax on eating habits – it also said that a tax would save the NHS £10m a year by 2025.
Official recommendations say we should get less than 5% of our energy from sugar. The report said that we currently get between 12% and 15%.
According to the report, 29% of people in the UK are obese, and this will rise to 34% by 2025.
Although the tax would not reverse the obesity epidemic, the report said that it would stem it. It said: “The tax would lead to obesity rates levelling off at around 29% - preventing 3.7m people from becoming obese.”
Alison Cox, from Cancer Research UK, said: "The ripple effect of a small tax on sugary drinks is enormous. These numbers make it clear why we need to act now before obesity becomes an even greater problem."
Jane Landon, from the UK Health Forum, agreed: "Countries which have introduced a tax on sugary drinks have not only reduced consumption, they have raised much-needed revenues for public health measures."
Several charities and high-profile campaigners, including celebrity chef Jamie Oliver, are calling for a sugar tax as part of a range of measures to cut obesity and the amount of sugar in children’s diets. This week, campaign group Action on Sugar took aim at the amount of sugar found in hot flavoured drinks, describing it as “shocking”.