Barnsley could become the 'poor relative of the NHS' if proposals to cut the town's health budget by more than £40m go ahead.
Figures published by NHS England show Barnsley stands to lose £41m, 13.5 per cent of its budget if a proposed change to the key health funding formula is introduced.
Currently, funding is weighted towards deprived areas with the highest health inequalities, but the move would mean a funding formula based on health needs linked to age, sex and location.
The current budget, announced in December last year, stands at £344m but this could be reduced to £303m.
But Rachael Maskell, head of health at trade union Unite said the proposals would impact disproportionately on deprived areas, such as Barnsley.
"In deprived areas, people don't live as long. It will cause more health inequalities which will be really detrimental to a place like Barnsley.
"If there is less money available, there is less money to spend and invest in making sure people don't get ill in the first place. Everything costs."
She said the cut could mean less money was spent on top drugs and treatments and operations such as hernia repairs, treatment for varicose veins and hip replacements and preventative medicine could all be affected.
Mark Wilkinson, chief officer of the NHS Barnsley Clinical Commissioning Group, which pays for health services for the town, said: "The CCG will want to understand why the government think we are getting more than our fair share, as this could mean we would lose vital NHS resources for Barnsley.
"Although the health of the average person in Barnsley has improved greatly over the last few years, there are still real inequalities between different areas of our country - typically between North and South."