BRITAIN would need to put a 20% "fat tax" on unhealthy food and drink to improve the numbers of people suffering diet-related conditions such as obesity and heart disease, medical experts warn.

Such a move should be combined with subsidies on healthy foods such as fruit and vegetables, academics from said.

Dr Oliver Mytton and colleagues at Oxford University said evidence suggested taxing a wide range of unhealthy foods was likely to result in greater health benefits than "narrow taxes" – although the strongest evidence related to taxing sugary drinks. They said one American study found a 35% tax on sugar-sweetened drinks in a canteen led to a 26% decline in sales.

Studies extending VAT on unhealthy foods in the UK could cut up to 2700 heart disease deaths a year, the researchers said, adding: "Evidence suggests taxes are likely to shift consumption in the desired direction... the tax would need to be at least 20% to have a significant effect on population health."