Whenever the powers that be ask the people what they need to solve some vast an unsolveable problem, the top answer that always comes back is "we need more information".
How do we cut down on teenage pregnancy? Kids need better sex education to give them the information they need to make informed choices.
How do we cut down on obesity? Parents need more information about what goes into products, so they can make informed choices.
People in the UK in 2011 have easier access to more and better information than at any previous time in history. Kids today know more about sex than Casanova and Lucrezia Borgia combined. Parents need only look at the packaging of food to gain a wealth of information about what is in it - all the ingredients are listed and there's a breakdown of calorific and nutrition information. And if there's anything you don't know, Google makes every question an easy question.
"We don't have enough information," is an excuse, and it just is not true.
The issue with teenage pregnancy is not that kids don't know they shouldn't be having unprotected sex. They know, but when the time comes they choose to take the risk rather than not have sex at all. Or they just don't think at all. Or whatever. It's not that they don't know, it's that they don't think.
For the overwhelming majority of people, the solution to obesity is simply a matter of "eat less, move more". That's it. There is no magic bullet, there's no special combination of foods that will do the job better. (And where there are foods we should eat more or less, that's well known too - nobody can reasonably claim not to know about "5 a day".)
These are hard problems to fix, either because there's no simple solution or because the simple solution requires time, dedication and discipline (and, frankly, is really quite painful).
But "we don't have enough information" is a lie, and it's a lie that is told to avoid taking responsibility for actually dealing with the problem.