Burger King to put energy labels on menu boards

Auckland nutritionist Lynda Smith said Burger King's move was positive because a lot of people were unaware of how much energy was in their food.

"It could influence what they buy - they might perhaps buy a smaller serve of fries or perhaps another type of burger, not such a high-energy burger."

Nutrition Foundation dietitian Sarah Hanrahan said displaying the energy in kilojoules was a "great place to start".

"It's a good first step, but you could go further. You do need context around it."

She urged fast food restaurants to adopt the healthy star rating system - an interpretive system endorsed by the Government which will be adopted voluntarily.