Wednesday, 14 April 2010

How public health targets are set


Helen Rumbelow at The Times has published an important article about the 5-a-day fruit and veg target which has recently been shown to have no effect on cancer risk. Rumbelow gives a fascinating insight into how these targets are plucked out of the air based on shoddy evidence (see also: drinking guidelines).

The key quotes from the article are:

“The world has gone mad with targets,” says Tim Lang, the first stop in my quest. I’d tried the Department of Health, and was told its five-a-day programme was announced in 2000, based on World Health Organisation advice about the role of diet in cancer, but that didn’t really tell the full story.

Lang, a professor of food policy at City University, remembers it differently. It was the late 1990s, the new Labour Government had come to power and set about instilling a target-driven culture in every aspect of British life.

Ain't that the truth?


“We all understand targets in the policy world. I remember being in the room when we were being briefed by Americans on five-a-day, which we adopted from them. They chose five partly as it was considered a nice round sum and partly because it seemed possible, given how low consumption of fruit and vegetables was.”

Because it seemed "possible"? Because it was a "nice round sum"? This is how worldwide health advice is formulated?

In 1991 the American Government adopted the five-a-day policy, as growing numbers of experts were stating that bad food was causing cancer. First and foremost among them was Britain’s esteemed Sir Richard Doll, the scientific hero who established the link between cigarettes and cancer. In 1981 he estimated that a third of cancer deaths in the West could have been avoided with a better diet.

And he happened to be wrong about this. This was recognised by impartial observers long ago.

“It was a pretty rough, arbitrary number, which is always the case with any target,” says Willett. 

OK, fair enough. There's no point arguing over whether they should have said 4 or 6 portions of fruit and veg a day, but where was the evidence for any of it?

But, he adds, the studies were fatally flawed.

“They were based on retrospective evidence — asking people about their diet after they had already got cancer, which can lead people to report differently. Also, the control groups were not perfectly random, the people who volunteer for that kind of thing are much more health-conscious individuals.”

And, as I have said before, these are the same problems you get with secondhand smoke studies. The studies are wide open to all sorts of confounding factors and biases.

Still, at least it wasn't a money-making exercise.... was it?

“It was Susan Foerster, the head nutritionist in California. She had the bright idea of promoting fruit and vegetable consumption in a state which was a big fruit and vegetable producer.”

Unbelievable. As the livid Counting Cats concludes:

The fuckers just made it up. Like booze units, drug bans, traffic calming, climate chaos, second-hand smoke, third-hand smoke… The evil little turdulently tinpot meddlesome ratbags they really are.

Of course, some people will say there was no harm done here. Eating fruit and veg is good for you, even if it doesn't protect from cancer. This is the last line of defence for all junk science.

And it's true, if you don't see anything wrong with spending millions of pounds on health campaigns based on fantasy figures. 

It's true if you think the public should be treated like ignorant savages who are incapable of making their own decisions. 

It's true if you only care about reaching arbitrary targets. 

It's true if you think that an obedient population is more desirable than a well-informed population. 

And if you believe all that, there may be a job for you in public health.