New Zealand's Health Star Rating system 'is very broken' - public health expert

Many New Zealand foods have a Health Star Rating to tell consumers just how good - or bad - the product is for the body.

The way the stars are allocated is currently under review, but following some criticism a public health expert says the whole system needs to be scrapped. 

That "at-a-glance" star rating stamped on thousands of packaged and processed foods should help you make on-the-spot healthy choices.

But one Kiwi cereal-maker claims some brands are gaming the system.

"Children are eating the equivalent of three sugar cubes or more for breakfast," says Scotty Baragwanath from Blue Frog Breakfast.

It appears that many kids eating the 'high-rated' stuff are actually consuming three teaspoons of sugar - before the school day has even started.

New Zealand shares this rating system with Australia, and many across the ditch say Baragwanath is bang on.

"There are certainly some products where the food manufacturers have deliberately manipulated the recipe in order to get the most amount of undermines consumer confidence in the whole system," says Parents Voice campaigns manager, Alice Pryor.

Ratings are based on an algorithm that sifts through all the kilojoules, fibre, saturated fats, salt and sugars of each product.

But how that algorithm allows some sugar-filled cereals to get top marks - means something is going wrong.

The five-year-old five-star rating system is nearing the end of a massive review, and some experts are speculating whether it's even worth fixing the glitches.

Dr Simon Thornley, a Population Health senior lecturer at Auckland University, says he doesn't even look at the ratings during his grocery shop. 

"I think the system is very broken," he said on Monday's episode of The Project.

"I think it misses the biggest issue in our diet - we're swimming in sugar in this country."

Foods like macadamia nuts are rated as unhealthy according to the system, due to their high content of saturated fat. However, recent evidence says sugar is the real culprit.

"The campaign to lower fat has let sugar in the backdoor," says Dr Thornley. "We're the third fattest nation in the OECD now."

"The Health Star Ratings are a golden opportunity to bring this knowledge to the streets, and yet it has ended up championing sugary products... I think it's a crying shame."

Watch the full interview above.