I’ve been described as a food fascist, and while I don’t sit down at the dinner table singing “Tomorrow belongs to me” I do watch what I eat. And sometimes what I am watching is a Macca’s Quarter Pounder. They have never done me any harm (photos on request, “commercial in confidence”), and at least you know when you’re eating in St Ronald’s domain that the toilets will be clean. So, on the basis of personal experience and occasional personal preference, I’m antagonistic to claims that the reason we are getting more obese as a nation is because we are eating too much fast food.
Yesterday’s Sun Herald carried a story which started:

FAST food could be subject to a new tax of up to 50 per cent under a plan to fight Australia’s worsening obesity epidemic.
The proposed fat tax would, hopefully, steer consumers away from calorie and sugar-laden foods and force them to choose cheaper, healthier options.
Similar to hefty tax rises on cigarettes, the move aims to slash illness and death caused by obesity.
The tax would bring the price of a Big Mac up from $3.25 to $4.88, and a $3 bucket of chips would rise to $4.50. Sydney sociologist Dr John Germov will float the plan at the Australian Institute of Food Science and Technology in Sydney tomorrow.
“We need a way of addressing the obesity problem because diets are notoriously unsuccessful — 95 per cent of diets fail,” Dr Germov said.

If Dr Germov was proposing a corresponding carrot (more calories required to eat them raw than they yield up)in the form of a subsidy for those of us who exercise, I might have been interested. But punishing people for eating fat, which is a necessary part of a diet, seems absurd.
If Dr Germov were a nutritionist, rather than a sociologist, he would know that Vitamin D is fat soluble – no fat, no vitamin D, and lots of babies with rickets. Recent research shows that to get the value of flavinoids from tomatoes you need to cook them in oil. Flavinoids also are fat, not water, soluble. So, to compare eating fat, which is beneficial in moderation, to smoking, which is not beneficial in even the smallest quantities, is absurd.
It’s also not fair to beat up on MacDonalds. I’ve done a bit of research on the subject, and it turns out that we eat fast food on average less than once a week, at least according to research by AC Nielsen. Nielsen says:

30 per cent of Australians ate at a take away restaurant at least once a week, and 64 per cent said they ate fast food at least once a month. This compared to a global average of 24 per cent and 51 per cent respectively.

What does fast food do to the calorie intake of the 30 percent who eat at a take away at least once a week? Well assuming that most are closer to once rather than 21 times a week, not much. Macdonalds handily provide a calculator where you can work out what you are consuming. My quarter pounder, large fries and inadvertently non-diet large Coke Sunday evening on the way back from Forster set me back 1,350 calories (US site, so unrepentantly wedded to imperial measures, which those of us over 45 can still relate to).
Given my build and activity levels this is probably a bit over half my daily requirements, but then it was only one meal. I probably eat 1,000 calories for dinner normally, so we’re only 350 up for the meal, and as it’s the only takeaway one in the week, 350 up for the week. But we’re only 350 up if we assume that I eat my exact calorie requirements every day for the rest of the week, which I don’t. Some days I’m over, and some I’m under, and in the total 14000 to 17500 calories that I consume, 350 is not going to turn me into a Tele Tubbie.
Actually, if I’d had the diet coke rather than inadvertently being served the sugared one, then I’d be bang on my normal 1,000 calories, and there wouldn’t be a problem. So, if you want to blame anything, blame the sugar, not the fat.
The reasons for national obesity are multiple, but they largely centre around what we eat in the home, not what we eat when we’re out, and the fact that we don’t walk anywhere much anymore. And I suspect that Mum is the biggest villain (which is why it is handy to have fast food as an alibi). But then, my Mum hasn’t learnt to logon, so she’ll never read this, and I’ll be OK, but then, she has the photos as well!