Nine-year-old friends Caoimhe Findlay, left, and Grace Meecham enjoy some oven-baked chips, considered more healthy than yogurt - at least according to the Health Star Rating system.

Chip lovers rejoice: crunchy potato fries are as healthy as some bran-based cereals, according to a controversial new food rating system.

New Zealand's new food star rating system was introduced last year to help shoppers make better choices about packaged foods..

But the scheme has thrown up some curious results, in Australia where the same star ratings system has been introduced, oven-baked potato chips had a high rating than apples, and pizza was found to have a higher rating than yoghurt.

READ MORE: Are KFC chips healthier than a scone?

New Zealand Nutrition Foundation chief executive Sue Pollard said the science behind the ratings was sound, but it wasn't a health claim and consumers should only compare products within a category.

"No food label can be all things to all people. The [stars] are an excellent way of comparing processed food within a category...They could lead to some confusion initially, if people compare foods that are substantially different."

She said foods with high ratings that would make a good lunch or breakfast were baked beans or eggs on wholegrain toast (four-stars), with added extras such as avocado, tomato, spinach, or leftover vegetables cooked with a little olive oil.

However, consumers could be forgiven for not even knowing there was a new one-year-old star rating system in New Zealand.

To get a high rating, foods have to be low in saturated fat, sugar and salt, and/or high in fibre, protein, fruits, vegetables, nuts or legumes.

New Zealand companies have been slow to take up the voluntary ratings system, but the most prolific collection are to be found on breakfast foods.

Sanitarium and Kellogg's cereals all have ratings, from two stars for Coco Pops to five stars for Weet-bix and All Bran. Some canned soup varieties have them, while others don't. The highest rating spotted on the shelves was for two different brands of tomato soup.

Budget dried penne pasta was also rated, four-stars, as were some single serve pasta sachets with a lower three-stars.

Sanitarium New Zealand general manager Pierre van Heerden said that it would take time for the packaging of foods to change to including the ratings, but more would be on the shelves later this year.

The benefit of the rating was that it was a Government system, so not based on what companies had decided their food was worth.

A spokesman for the Ministry of Primary Industries said the ratings system wsa simple: "The more stars, the healthier the choice."

"The system is not about telling consumers what they should be eating. Instead it allows for consumer choice and aims to make it easier for people to compare similar products and choose the healthier option by taking the guesswork out of reading food labels," a spokeswoman said.

Companies were encouraged to change the ingredients of their products to achieve a higher rating.

THE VERDICT

The majority of Wellingtonians approached near a supermarket said they had heard of them, but not all used them when buying products.

Erin Riordan, a 21-year-old admin worker, said that she paid more attention to price and whether she liked a food than the nutritional information.

If one product had more stars than another would not always be enough to sway her to take it to the checkout, she said.

"But if I'm buying for my sister I will look at the ingredients because she has allergies. For me, price would be how I would pick something, or I would chose what I have had before."

Dianne Trewavas, a 64-year-old policy analyst, said she used nutritional information to determine the levels of fat and sugar in foods that she bought, but had not noticed the stars.

The idea behind them was good and she would use it in the future, she said.

Others, like businessman Logan Westwater, 38, and student Ben Humphries, 19, said that they thought they had enough knowledge of what foods were good or bad without looking.

"It's often obvious if something is unhealthy or not," Humphries said. "If I'm trying to chose, I'll pick the food that looks like it will taste better."

OTHER HEALTHY FOOD GUIDES

The Heart Foundation red tick: Introduced 21 years ago and designed to highlight the healthiest products with in a certain food category. Each product is independently tested to make sure it fits the healthy criteria and randomly tested every few years. A new two-tick system was introduced in 2014 to identify the best products in core food groups, such as fruit and vegetables, nuts and cereals.

5 a day: Some packaged fruit and vegetables display the 5+ a day charitable trust's logo to help promote the eating for five or more servings of fresh fruit and vegetables a day for adults and young children

SPCA blue tick: On many animal products to certify that they were produced under proper animal welfare conditions, taking into account freedoms from pain, hunger and able to express natural behaviours. Started in 2001 with the auditing of egg production, pork was added in 2009, chicken and meat followed in 2011 and turkey in 2012.