Oh it could, could it?
Those 3,000 "saved" people aren't going to live forever. Eventually, they'll die of something else (which, given that most people in the UK die of strokes, heart disease or cancer, means cancer given that the other two have been ruled out). What the report (or the report of the report) means is that 3,000 people will have their lives extended if there's a tax on fatty foods. That's not what it says, though.
This is just the sort of report that governments like. Here in the UK, we don't have tax on absolute essentials, of which the classic example is food. Imposing a tax on junk foods would rake in about £2,000,000,000 extra revenue a year, so clearly it's something that would please the Exchequer. Being able to justify it as a way of "saving lives" is perfect for them. Basically, though, the general public would be paying 2 thousand million quid to "save" 3 thousand lives, or two thirds of a million per life.
There must be cheaper ways to save lives than taxing dairy products.