The harsh realities of poverty in some parts of Wales have been revealed in analysis of the last census.
Merthyr Tydfil has the highest level of long-term illness in the UK
People living in some parts of the south Wales valleys have just one dentist for every 9,000 people.
And in former mining communities like
Merthyr Tydfil, 11% of people are now classed as disabled or long term sick.
The study which was carried out by Sheffield University found that the gap between the rich areas of the UK and poor areas of Wales is widening.
In some areas of the UK there is a dentist for every 2,500 people but the problems of many in Wales have been well charted with, in some places, hundreds queuing to register with an NHS dentist.
Two hundred years ago Merthyr prospered at the centre of the UK's steel and iron industry - but that prosperity has now faded.
Merthyr dentist Huw Jones has to cope with more than 9,000 patients
Dentist Huw Jones has to look after more than 9,000 patients.
His father Hefin Jones, a GP in the town, is faring no better. He has 10,000 registered patients.
Huw Jones says the image of the town is a problem in attracting health professionals.
"The main perception a lot of people have is that the areas is dominated by heavy industry and estates with troublemakers and disruptive behaviour and drunkenness," he said.
"That perception needs to be challenged because it isn't actually true for most of the population."
His father Hefin Jones said there were "patches of bad health. There are people who are economically disadvantaged and that's associated with bad health and shows up in the figures for Merthyr".
Former CBI director Ian Kelsall, now chairman of Pontypridd NHS Trust, blamed the area's poor health on lifestyle factors.
"People not eating the right sorts of foods, smoking and drinking, all those things are taking their toll," he said.
"On the other hand a lot of people are living longer as a result of medical improvements.
But cultural historian Peter Stead said the onus was on the people of Merthyr to develop their own style, building on the towns historical importance but looking to the future.