Tom Smith has a little secret. It's so secret that none of his friends at his Broward County condominium know. So secret that his two grown daughters don't know.

As with most secrets, this one involves some subterfuge: Tom Smith tells people that he and his 79-year-old wife, Alice, go to a senior-citizens center five days a week to volunteer - which he does, serving meals in a cafeteria line.

What he doesn't tell them is why: They go for the free lunch. And so do a lot of other people.

Smith wasn't supposed to need any kind of handout when retired 22 years ago and moved with his wife to sunny South Florida. Back in Chicago, Smith earned enough as bar owner and sports official so that his wife never had to work outside their two-bedroom, two-bath home. They raised two daughters and put money away for retirement. That came in 1973, when Smith was 60.

The Smiths soon moved south to enjoy the sun and sand, settling into a two-bedroom, two-bath condo that overlooks a well-manicured golf course a few blocks from the ocean. They went on cruises, played golf, sat in the sun and enjoyed themselves.

Then, the Smiths' nest egg ran out.

"At the time I retired 22 years ago I had enough saved, but times change, the amount grew smaller, and with the price of everything inflated, you get yourself into a squeeze," Smith says.

Today, Smith's Social Security check is the couple's only income. They spend five days a week, from 9 a.m. to noon, at the senior-citizen center. They tell friends they go as volunteers, and they do work. Besides serving lunch in the cafeteria line and pouring coffee, they cheer up friends and do whatever chores they can.

The Smiths won't ask their daughters for financial help - or even tell their daughters of their problem.

And so there are no more cruises or, for that matter, anything that would require much money. "All we do is walk around malls and go to the center," Smith says.

Were he to do it all again, he says, he would wait to retire. "If you retire too early, you're lost.

Nola Durant calls senior citizens like the Smiths the "hidden poor," once-comfortable retirees who have outlived their savings and no longer can put food on the table. Durant, director of the Northwest Focal Point Senior Center in nearby Margate, sees a large number of these retirees.

They are hidden because often they won't admit their plight. Because of that, it's impossible to calculate their numbers. They maintain a comfortable facade, continuing to drive cars bought years ago, living in oceanfront condos or big houses, wearing jewelry bought when they had money. But Durant and other social workers say a number of senior citizens receiving hot lunches today can be considered poor.

"People have outlived their money," says Ann S. Brandt, director of senior-citizen services at Jewish Family Service of Broward County.

Others agree. "A lot of people came to Florida with money, purchased very nice condos and paid for them," says Edith Lederberg, executive director for the Area Agency on Aging of Broward County. Then they may have been hit by a medical catastrophe. Or like the Smiths, their money simply ran out. "But they still have to pay taxes, telephone, maintenance, recreation leases and medical expenses," Lederberg says. "So what do they do? They don't eat."

Or they eat free lunches at senior-citizen centers, which offer a variety of special programs in addition to the meals.

"A lot of older people, especially condo people, have the mentality that they have to contribute something to society," says Victor de Souza, coordinator of the senior-citizen program at the Hepburn Social Services Center in Hallandale. "They're givers, not takers. They aren't accustomed to taking handouts. So there is a tradeoff. They come to the center, contribute the time - and in return, get a hot meal.

In short, the lunches are designed to be pride-savers. "It's very hard for older people to accept anything they consider welfare," says Jo Reed, spokeswoman for the American Association of Retired Persons in Washington, D.C.