A SNAP survey of Neath and Port Talbot's hospitals found that half of their patients did not need to be there.
Out of the 129 patients taking up beds at the time the Abertawe Bro Morgannwg University Health Board survey was carried out, 67 were classed as fit enough to be cared for in the community.
Although this figure related to a single day, health chiefs say it is representative of the everyday reality.
ABMU is proposing to close one of the hospitals in the Neath Port Talbot locality — Gellinudd in Pontardawe — and use the resources this will free up to enhance community-based care.
At the moment the closure is only being discussed as a possibility as part of ABMU's Changing for the Better (C4B) programme.
It will be raised at a drop-in event hosted by ABMU at Pontardawe Arts Centre next Friday and subsequent events in the Neath Port Talbot area between now and late December.
Only when the engagement process ends will the health board come up with definite proposals.
A report presented to ABM Community Health Council's Neath Port Talbot committee outlined changes in the way frail and elderly people are cared for.
Hospitals are now seen as a last, rather than first, resort with the emphasis now on an enhanced Community Resource Service (CRS) model.
The idea is that people only stay in hospital when they need acute care. Once they are well enough to leave they are supported to live as independently as possible, either in their own home or some other community setting such as a nursing home.
"Discussions with Neath Port Talbot Council social services have confirmed a strong commitment to further developing capacity within the community resource services for the population of Neath Port Talbot," the report states.
The 67 "medically fit" patients in the county's hospitals could, it said, could either go home with support, or to an alternative such as a nursing home.
CHC member and former Neath Port Talbot councillor Clive Owen said public perception was important, as some people would see the loss of Gellinudd as a cutback.
"We are here as a watchdog," he said. "Are our patients going to be better off this way?
"I think they are, but it has to be workable. I know social services and I know there is a clash between the two cultures of nursing and social services.
"As long as we get over that it will work, but I do worry about it. We are here to make sure the patient gets the best deal."
ABMU planning director Paul Stauber said the two organisations had worked so closely together there had been a "blurring of the boundaries".
It is a similar situation across Carmarthenshire.
Director of planning, performance and delivery at Hywel Dda Health Board Tony Chambers said: "Our evidence shows that up to 40 per cent of patients in our hospital beds would not need to be there if the right services and support was in available in the community. We want to develop our primary and community care services to reduce inappropriate use of hospital beds and prevent this from happening, increasingly providing care within the community and in some instances, within a patient's own home."