from the Congressional Budget Office
If current laws governing taxes and spending did not change, the condition of the federal budget would worsen considerably over the next three decades. Growth in federal spending would continue to outpace growth in federal revenues, leading to ever-larger budget deficits.
CBO projects that federal spending on the major health care programs would grow larger than spending in any other category if current laws generally remained unchanged. Driven particularly by growth in Medicare outlays, spending on those programs would account for 40 percent of federal noninterest spending in 2047, compared with 28 percent today. Two factors explain the projected growth in spending on major health care programs: aging of the population and rising health care costs per person (that is, excess cost growth).
Health Care Spending Today and in the Future: Impacts on Federal Deficits and Debt from Congressional Budget Office
Source
https://www.cbo.gov/publication/52913