Perth's newest adult hospital, Fiona Stanley, has been ranked the poorest performer among metropolitan facilities in an audit which reveals none of WA's hospitals have fully complied with a mandatory policy to serve healthier food to visitors.

Key points: Food and drink outlets in hospitals must serve at least 50 per cent "healthy" foods

Food and drink outlets in hospitals must serve at least 50 per cent "healthy" foods Fiona Stanley Hospital has the lowest rate of compliance in Perth at 11 per cent

Fiona Stanley Hospital has the lowest rate of compliance in Perth at 11 per cent Health Minister Roger Cook says it is not good enough and hospitals must improve

The Health Department examined the variety of food on offer at cafes, vending machines and ward trolleys at 25 health facilities across the state, after Health Minister Roger Cook gave them a six month deadline to meet the standards.

The Healthy Options WA: Food and Nutrition policy states that food and drink outlets in hospitals must include a minimum of 50 per cent "healthy" foods, and uses a "traffic light" labelling system similar to that used in school canteens.

The policy requires WA hospitals to sell a maximum of 20 per cent "red" or unhealthy foods. ( ABC News: Alisha O'Flaherty )

Half of all food and drinks sold must be "green", or low in saturated fat, added sugar and salt, with a maximum of 20 per cent "red" or unhealthy foods.

Of the 215 cafes, vending machines and ward trolleys assessed, 47 per cent complied.

Mr Cook said the results were not good enough.

"I do consider it too low," Mr Cook said.

Fremantle Hospital performed the best with 81 per cent of food and drinks policy compliant. ( ABC News: Alisha O'Flaherty )

"I want [hospitals] to do better and I want them to work with their food vendors and with a whole range of commercial entities that they have within their hospitals to make sure that we all live these values.

"It's so important that while we have a department that does a great job at talking about healthy food, healthy living, making sure people stay healthy, that they provide those opportunities and become real exemplars for those values themselves."

Food hall 'treats' blamed at Fiona Stanley

Fremantle Hospital achieved the highest rate of compliance at 81 per cent, while Fiona Stanley Hospital recorded just 11 per cent, which Mr Cook attributed to the presence of a food hall.

Fiona Stanley Hospital was the poorest performer among Perth facilities in the audit. ( ABC News )

"It's interesting and a bit disappointing and we're looking to get further information about that," he said.

"Perhaps one of the options we're looking at here is rather than taking each food outlet in isolation, we consider the fact that Fiona Stanley has a food hall which displays a range of outlets that have very healthy options, and just a few which perhaps provide more of those treats and higher calorific foods.

"So we perhaps need to look at modernising the policy as well to make sure it reflects the reality."

Eight smaller regional hospitals as well as the department's own cafe at its East Perth head office were among nine facilities in the audit that did not comply with the policy at all.

"That's wrong and I expect the head office to take measures to actually correct that," Mr Cook said.

"That's where a lot of the policy gets driven from, that's where we expect the policies to be lived in the very first instance."

Hospitals under pressure to improve

The audit showed there had been significant improvements in compliance since the last survey in 2016.

The greatest increases were in WA Health-operated cafes and kiosks, where there was a 47 per cent jump in the number that were compliant, while there was a 38 per cent increase in the number of drink vending machines meeting policy requirements.

Mr Cook said hospital boards were taking the issue seriously.

"They're doing a lot of work in looking into the culture of the organisations at the hospitals that they run, and so it's not surprising to see that some progress has been made. [But] we want them to do a little bit more," he said.

Roger Cook says there will not be a heavy-handed approach to the problem. ( ABC News: Alisha O'Flaherty )

"I've met with all the health service provider chairs … and sort of said to them, 'look here's the report, it's not good enough, we want you to improve'.

"I'm expecting them to come back to me with a range of measures and feedback in terms of that. [But] we're not going to take a heavy-handed approach to this."

Cancer Council WA obesity prevention manager Kelly Kennington said the progress was a positive sign.

Kelly Kennington from the Cancer Council WA says hospitals must take a leadership role. ( ABC News: Alisha O'Flaherty )

"Within the last 12 months, since the Minister gave a really strong directive for hospitals to lift their game, we have seen a really big improvement," she said.

"But there's obviously still a long way to go.

"We need hospitals to be taking a leadership role in this area. The policy is there for a reason, and that reason is that hospitals are about health and making people better."

Call for sugary drinks to be banned

But the Australian Medical Association of WA's immediate past president Omar Khorshid said there was no excuse for hospitals not meeting the requirements, given the policy had been in place for about a decade.

"They've now been given fair warning by the Minister over a year ago, so clearly the policy isn't working and it's time to strengthen that policy, make it clearer and in particular, bring in a ban on sugary drinks in West Australian public hospitals," he said.

There are calls for the sale of sugary drinks in WA's public hospitals to be banned. ( ABC News: Alisha O'Flaherty )

Dr Khorshid said New South Wales hospitals had stuck to a ban on sugary drinks for some time.

"It hasn't put the businesses that run the cafes in these hospitals out of business, because they're still selling other products and they are selling healthier products," he said.

"It's an ability for our health system to take a stand and to say so much of the obesity and the poor health, the diabetes in our community, is due to lifestyle choices

"We should be leading the way in our hospitals and helping people make healthy choices."

The audit report said some hospitals had taken further action since the survey, including the "voluntary removal of sugary drinks" or investigating the feasibility of such a move.