It could see not just a tax on obvious junk foods such as pizzas, burgers and chicken drumsticks, but full-fat milk, fizzy drinks, crisps, chocolate, cheese and even butter could also cost more.
According to a report in The Times this morning, the Prime Minister's strategy unit has drawn up a paper called 'Personal Responsibility and Changing Behaviour', which will look at how to cut soaring obesity levels.
Initiatives also include possible changes to labelling, including warnings, and a national sports drive.
Other suggestions would see regulated nutritional standards for common processed foods and drinks.
The fat tax, which has been dubbed "Fat Vat", is opposed by the Food and Drink Federation, which has said that it could have a serious impact on low-income families. However, those in favour of the tax argue that it could encourage people to buy non-taxed healthier foods.
But most agree that the solution to obesity is going to be more complicated than simply making fatty foods more expensive. Obesity rates have risen from under 10% in the 1980s to over 20% of people today.
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