Consider these two lines back-to-back:

Consumers are saying they want smaller portions and healthier options.

We know that just having healthy options on the menu won’t change the nation’s habits.

Well which is it? Do people want healthier options, or will having healthier options on the menu not change habits?

As for the numbers, according to food surveys calorie consumption has been trending down in the UK for the last 15 years, exactly the time period the article cites the rise in childhood obesity. If rising calorie consumption isn't the primary cause of increased obesity, targeting calorie reduction seems more like, "We have to do something; this is something."

But wait! Those numbers are no good. Problem is, that's been true as long as we've been studying nutrition. If we don't even have good numbers we're not ready to make policy decisions.

But if we must have a policy decision, you know what else studies show? Plans that rely on calorie counting fail roughly 98% of the time. Eliminating processed food and added sugar seems to work pretty well, but no one is coming up with the money to study that. I wonder why.

And finally, if you mandate that "single serving" pies have a calorie cap people will simply buy the next larger size, which will probably be larger than what they're getting today.