For years, the nation's workers have been retiring earlier and earlier. In 1950, nearly half of the men 65 and over were in the labor force; today, only 19 percent are.

That trend seems destined to change.

The House voted Wednesday night to raise the normal retirement age for receipt of full Social Security benefits from 65 to 67 early in the next century.

Meanwhile, the Senate Finance Committee voted Thursday to raise the age to 66 by the year 2015.

Under both bills, workers could receive Social Security benefits by retiring at 62 but would have those benefits more sharply reduced by early retirement than they are under current law.

Making people work longer or suffer financial penalties is one way to eliminate Social Security's long-term deficit. But Social Security is so pervasive in the economy that raising its retirement age would set a pattern throughout the nation.

The issue produced a bitter House clash.

Social Security subcommittee chairman Rep. J.J. (Jake) Pickle (D-Tex.), sponsor of the proposal, argued that "there is nothing sacrosanct about age 65" and that "longevity has increased dramatically" since passage of the Social Security Act in 1935.

His supporters argued that people can now work longer and that older workers will increasingly be needed in the labor force because continuing low birth rates will mean a scarcity of young workers in the next century.

Statistics support Pickle on longevity. Life expectancy for an infant born in 1940 was 63 years. For one born in 1979, it was nearly 74.

But Rep. Bill Richardson (D-N.M.) declared, "Longer life does not necessarily mean better health."

Rep. James M. Shannon (D-Mass.) agreed: "Survey after survey shows that a great many people, perhaps two out of three, retire not because they want to but because of: first, poor health; second, mandatory retirement; third, lack of skills; and fourth, job loss."

Who is correct? Dr. Eric Kingson of the University of Maryland at Baltimore, in a series of articles, said numerous studies of those who dropped out of the labor force before 65 found that one-half to two-thirds of them said they did so because of poor health. His own studies showed higher death rates for very early retirees, suggesting they left work because they could no longer perform.

But Robert J. Myers, former chief actuary of Social Security and staff director of the presidential commission whose recommendations led to the current bill and of which Kingson was a staff member, disputed many of these conclusions.

Dr. Jacob J. Feldman of the National Center for Health Statistics, testifying before the commission last June 21, said that while people are living longer, "The proportion of men in the 50 to 69 age segment reported as being unable to work because of illness increased between 1970 and 1980."

At the same time, however, he reported that one NCHS survey suggested that only 37 percent of men between 65 and 67 were unable to work or limited in what they could do. "This leaves 63 percent being reported as fully able-bodied with respect to work," he concluded.

There is also controversy on the availability of jobs in the year 2015. But many students of this, such as economist Lawrence Olson, vice president of SAGE Associates, an economic analysis and consulting group here, believe there will be sufficient jobs to keep older Americans employed.

Olson, who projected older workers' labor force participation in the year 2005, said in an interview: "There is a widespread belief among economists and labor-force experts that there will be jobs for older people" because continuing low birth-rates will not produce enough young workers.