If foods that are high in fat and sugar were to cost a lot more than they do now, chances are at least some people would eat less of them. At least that's the theory, based on the fact that sales of cigarettes went down years ago when they were taxed. But could such a 'fat' tax ever work?
That's the question being asked by the Danish government, which has become the first in the world to impose a tax on junk food. Yet Denmark has nothing like the rate of obesity that we see in the UK, where allegedly two-thirds of adults are either overweight or obese (we're the fattest in Europe apparently).
And that's the problem, the Danes - who are already the most highly taxed population in Europe - don't want to follow our example. So now foods like chocolate, cakes, sweets, ice cream and others that are high in fat and calories cost a lot more over there than they used to.
But could the same thing work here? Any idea of a hike in junk food prices won't even get a look in, thanks to the current government's strategy of encouraging people to take responsibility for their own health (in other words, no nannying). Is that wise, though, given that we're looking at a 20 increase in type 2 diabetes by 2050 if something isn't done about our diet?
Watch tonight's Panorama for more about how the tax is working in Denmark.
What's your view on the idea of a fat tax? Would it really stop people eating so much junk food?