Dear Dr. Sarah Wollaston MP

I write this open letter to you in the hope that you have been grievously misquoted by the Daily Mail. For it would be painful to have to believe that a sitting MP, and a qualified doctor to boot, could be quite so ill-informed about food, prices and obesity. It is thus my hope that your words have been manipulated by the newspaper rather than that you actually believe any of this tosh. For example, you are quoted as saying that:

'There is a huge amount of personal responsibility. But it is now so serious we need to state to step in and take some measures.

'The choice is you either do nothing and carry on saying it's all down to personal choice and you continue to pick up a huge bill through the NHS.

'We have to take out junk food calories and help to get people moving and more active.'

The problem there is that obesity does not cost the NHS anything at all. Indeed, the price to the NHS of obesity is negative. The reason being that the NHS is a system of lifetime health care and those who are obese die earlier. Yes it is true that they incur healthcare costs while alive and fat: but these are more than outweighed by the savings to the NHS when they are dead and buried and not requiring those longer years of health care.

This means that there are substantial private costs to people of being lardbuckets, entirely true, but it is not true to then say that there are public costs to their being so, as you well know.

'One of the reasons why the most disadvantaged people are running into difficulties is partly because the healthy food is more expensive.

'If you are struggling on a budget, you are much more likely to pick food on special offers. But all of the special offers tend to be on crisps, sweets and junk food.

That is also not true. Rice, beans, onions and tomatoes may not be a very interesting diet but it is still both healthier and vastly cheaper than any form of junk food calorie for calorie, whatever the BOGOF or discount that is being offered. This is something that we both know and so for the Mail to be quoting you as it did is obviously something you'll want to correct.

And finally the paper seems to be making a good attempt at making you look like an idiot:

She warned voluntary agreements with big chains had not worked and regulation was now needed to force stores to offer discounts on fruit and vegetables.

This is price fixing and price fixing does not work. By definition price fixing does not work: clearly a Tory MP is well aware of this fact for the following obvious reason. If we fix prices below the market clearing price then we will have fewer suppliers willing to produce at that price. We will also have more people desiring to consume that good or service at that price: the result is instant shortages of those goods and or services. We need only to look at the provision of toilet paper in Venezuela, well reported recently, to see that. Similarly, if we fix prices above the market clearing price then we find that consumers desire to purchase less of these goods and services while producers will be squeezing every extra unit out they can. Leading, as the European Union showed us when they did it, to vast gluts in the form of butter mountains and wine lakes.

Price fixing thus leads to either dearth or glut unless we fix those prices at the market clearing price itself. In itself that has a problem for as you well know we don't in fact have any other mechanism than the market itself to work out what that market clearing price is. But even if we did, again as is obvious to both of us, what's the damn point of fixing prices where they would be anyway?

Quite clearly you'll want to make sure that the Daily Mail corrects this terrible misrepresentation of what any sane or sensible person could possibly believe on this subject. My suggestion is that you start by calling 020 7938 6000 and ask for a certain Mr. Paul Dacre. He should be able to sort out matters for you.

Yours etc

Tim Worstall