AAP, Seven Network (Operations) Ltd :

Nursing homes are allowing some residents to waste away to skeletons weighing as little as 28kg, potentially leading to other serious medical conditions, health experts claim.

They say malnutrition of the elderly often goes unrecognised in nursing homes, hospitals and by relatives, The Weekend Australian reports.

It was also common for patients to shed more than 20kg before the problem was spotted and steps were taken to help them, the newspaper said.

One dietitian told the newspaper some nursing homes did not become alarmed if an elderly resident's weight dipped because it made them "easier to lift".

Another expert, Peter Lipski, a staff specialist in geriatric medicine at Gosford Hospital on the NSW central coast, called on carers to give elderly people high-energy snacks between meals.

He said it was a myth that it was normal for elderly people to lose 20kg to 30kg.

"There is too much emphasis on low-fat diets and low salt for patients with heart disease and diabetes ... their food is bland and they don't eat it," Dr Lipski said.

A new study of elderly patients admitted to Williamstown Hospital in Melbourne has also revealed that 62 per cent of the 75 patients assessed were either at risk of malnutrition (41 per cent) or actually malnourished (21 per cent).

Of those, 20 out of 47 had previously been in other hospitals or nursing homes.