Teresa Ghilarducci wasn’t surprised when the U.S. Labor Department recently released statistics showing that for the first time on record there are more older workers than teens in the nation’s workforce.

“Seventy is the new 17,” says Ghilarducci, director of the Schwartz Center for Economic Policy Analysis at New York’s New School for Social Research. “Seniors are now overrepresented in low-income jobs normally associated with teens.”

Typical is Dave Adams, 78, who retired from Connecticut manufacturer Fafnir in the early 1990s. He first went to work as a grill chef and dishwasher at a fast-food place. Now he works 25 to 30 hours a week at the West Hartford Senior Center, he says, “setting up tables, doing mailings, monitoring the fitness center—whatever they need.”

“Senior employment surpassing youth employment is a ripple effect of a horrible economy,” said Carl Van Horn, director of the Heldrich Center for Workforce Development at Rutgers University. “Older workers are being laid off or forced into retirement, their 401(k)s are losing value, and they’re forced to take post-retirement jobs to feed their families.”

Until now, Van Horn says, “they wouldn’t have been interested in working modest, entry-level jobs, but now they’re willing to settle for much less.”

In 2008, workers 55 and older represented 18 percent of the workforce and younger workers only 14 percent. By 2018, older workers are expected to make up nearly one-quarter of the nation’s labor force.

The Labor Department began collecting such statistics by age in 1948. This is the first time the numbers have shown workers 65 and older exceeding the ranks of workers age 16 to 19.

Though the increase in older workers may have accelerated with the recession’s onset, the trend has been under way for more than 20 years as the huge baby boom generation ages.

Old or young, job seekers face a daunting challenge these days.

Olivia Meny, 19, a rising sophomore at Clark University in Worcester, Mass., started looking for a summer job in March, applying for camp counselor jobs, and found nothing. After arriving home for the summer at West Hartford, Conn., she spent three or four weeks scrounging for work at dozens of retail and food establishments.

“Some places would say they were accepting applications but not hiring. Other times, I would walk into a store, and someone would tell me they were hiring. But then the hiring manager would say, ‘Why did you fill out an application? We’re not hiring.’ ”

“It was discouraging,” she says. “I need the money for tuition. I like to work, I want to work,” She eventually landed a job as a restaurant hostess at $9 per hour.

Gene Burnard, publisher of the career website Workforce50.com, sees the same kind of discouragement among job seekers at the other end of their lives.

“I get e-mails daily from people saying, ‘please find me work,' ” says Burnard. “We’re all seeing older workers in places like Dunkin Donuts, CVS and Starbucks.”

“Historically, teens and young adults made up the bulk of the restaurant industry workforce,” says Annika Stensson, director of media relations with the National Restaurant Association. “But now that demographic is changing. Those older employees will be a critical source of employees for the restaurant industry.”

Diane Cadrain is a freelance writer, attorney and art quilter in West Hartford, Conn. She writes frequently on employment issues.