If the proposal is accepted by the Welsh health board obese people will have to complete a weight loss program before they can go ahead with operations.
Also the Cardiff and Vale University have requested that if accepted smokers should go on a similar program before they can have any operations.
It is thought that the board would have cut costs by £90 million had they began the proposal at the start of the year and would have broke even.
If the proposal was to go ahead it is thought that they could save between £41,941 to £437,650 a year by allowing this.
Andrew RT Davies, Tory leader in the assembly, said: “Whilst the increased availability of courses for smoking and obesity is to be welcomed, I am concerned that failure to participate in these will be used as an excuse to delay operations for patients in need of treatment.
“The health board must give assurances that this will not be the case.”