Consumer group Choice has criticised a number of major food manufacturers for so far failing to put health star labels on their products.

Consumer group Choice has slammed major food manufacturers including Kellogg's for failing to sign up to the federal government's voluntary health star labelling regime.

Under the system, launched in December, food products are scored between half a star and five stars according to their energy, fat, sugar and salt content.

So far, supermarket giants Coles and Woolworths have the stars on their private labels while some Sanitarium, Nestle, Uncle Tobys and Lion products also display them.

However, Choice said a number of companies, including US multinational Kellogg's, were refusing to take part.

"Food manufacturers have been on notice since June last year to implement the new health star scheme however iconic brands such as Kelloggs, McCain and Mars are still refusing to serve up the information consumers need," Choice spokesman Tom Godfrey said on Tuesday.

"It's just not good enough that a major player like Kelloggs, that sells popular brands Just Right, Special K, Coco Pops and Nutri-Grain, are withholding basic health information and that's why we have launched this campaign."

He said the labelling system cut through "marketing hype" and made it easier for consumers to make healthier choices.

Kellogg's said it was not in a position to comment.

Health groups have been calling for the voluntary system to be made mandatory, and say most Australians support making it compulsory to help battle obesity.

Australia has one of the highest rates of obesity in the world with 63 per cent of adults and one in four children being overweight or obese.

The federal government developed the star rating system with state and territory governments, the New Zealand government, as well as industry, public health and consumer groups.

COMPANIES THAT HAVE SO FAR FAILED TO USE HEALTH STAR RATINGS:
*George Weston (TipTop)
*Goodman Fielder (Helgas, Vogels, Wonder White, Lawsons, White Wings)
*Kellogg's (Just Right, Special K, Rice Bubbles, Coco Pops)
*Mars (Dolmio, KanTong, MasterFoods, Uncle Ben's, Mars confectionary)
*McCain (Frozen veggies, frozen meals, pizzas)
*Mondolez (Kraft, Belvita and Philadelphia)
*PepsiCo (Smiths, Quaker, Doritos, Red Rock, GrainWaves)
KELLOGG'S CEREAL BRANDS AND THEIR STAR RATINGS:
*Just Right 4 stars
*Special K Original 4 stars
*All Bran Original 5 stars
*Coco Pops 2 stars
*Crunchy Nut 2 stars
*Fruit Loops 2 stars
*Mini-Wheats Little Bites Original 4.5 stars
*Nutri-Grain 2 stars
*Rice Bubbles 3 stars
*Sultana Bran 4 stars
Source: Choice