Calorie counts on menus 'prompt healthy choices'

Not.

Putting calorie information on menus encourages healthy eating - but only in a limited way, a review of the scheme in the US shows.

Researchers quizzed customers before and after a law was passed in New York in 2008 forcing restaurants to display the nutritional information.

The study by the NY Health Department showed one in six used the information - with most reducing their intake.

But...

However, overall there was no significant change in average calorie consumption before and after as some people were consuming more calories in 2009.

This was partly explained by changing practices at some of the restaurants. For example, energy consumption increased by nearly a fifth at Subway where large portions were heavily promoted.

And...

The research into how New Yorkers behaved after calorie information started being displayed on menus proves one thing - there is no silver bullet when it comes to changing behaviour.

Overall, consumption hardly changed after the law was introduced. That was partly because just one in six used the information at all.

Instead, the study suggests that the actions of industry can have much more influence.

One chain - Subway - saw calorie intake jump by nearly a fifth despite displaying calorie counts. The likely reason? It promoted large portions.

By contrast Au Bon Pain and KFC saw the biggest falls in energy consumption. But this was not wholly because customers were choosing to change their behaviour.

Instead, the two companies changed their menus...

Viva la no difference.