Medicare's Office of the Actuary estimates the cost of the nation's health care will hit $4.6 trillion by 2020.

Federal officials say that number would account for about 20 percent of spending in the U.S. economy.
    
According to Thursday's Medicare report, health care spending in 2020 will average $13,710 per person in the U.S. By comparison, that number will be around $8,650 per person this year.

"Most of us understood the health reform law was about expanding coverage, not cutting costs," health policy expert Joseph Antos told Kaiser Health News.

White House Deputy Chief of Staff Nancy-Ann DeParle drew a different conclusion.

"The bottom line from the report is clear: more Americans will get coverage and save money and health expenditure growth will remain virtually the same," she wrote on the White House blog.

Economists and statisticians warn the trend in health spending cannot be sustained. Nevertheless, they say it doesn't appear to be slowing down.
    
A deal over the nation's debt limit, however, might succeed in slowing down health care costs.

The actuary's estimates for health care spending are published in the journal, Health Affairs.