Guiding Stars, the US nutrition labelling system, has partnered with Apple's iPhone's to create an app that hopes to offer consumers a "good-better-best" rating system for their groceries.

The app will identify foods on consumers' shopping lists that provide the most nutrition for the calories, the company said on Thursday (1 October).

The healthy shopping app will be offered to new users for 99 cents and is free for current users of the iPhone's ReachEverywhere's Shopper app.

The system will allow consumers to "browse and compare" Guiding Stars rated food items within Shopper, add Guiding Stars rated items to their shopping lists and create multiple lists for specific stores, situations or recipes.

"We are proud to be the first nutrition navigation system to provide iPhone users an application that will help them make healthier choices for their family and save time in the supermarket," said Jaica Kinsman, web community specialist at Guiding Stars Licensing Co. "The Guiding Stars and Shopper application partnership will provide consumers around the country more access to our popular nutrition navigation system and is an easy-to-understand tool to help them choose foods for their families that provide the most nutrition."

Guiding Stars looks to "credit" food on the presence of vitamins, minerals, dietary fibre and whole grains - and "debits" products for the presence of trans fat, saturated fats, cholesterol, added sugars and added sodium, the company said.

Foods are then awarded zero, one, two or three stars - one star means good nutritional value; two stars, better nutritional value; and three stars, the best nutritional value.

Food labelling is becoming a hot topic in the US, with Supervalu introducing its own labelling scheme earlier this year to encourage consumers to buy healthier food. The system involves colour-coded labels on shelf facings underneath products that meet selected nutritional criteria.

Price Chopper and Hy-Val also adopted a nutritional scoring system - NuVal - which rates food based on its nutritional content, while a Smart Choices programme was launched in the US in August across hundreds of products in a bid to help shoppers eat more healthily.