The signs advertising Bethesda-Help are tacked on church bulletin boards and taped to clinic walls throughout the affluent Montgomery County community. During most of its 15-year history, the volunteer agency has been primarily concerned with transporting the elderly to medical appointments and supplying emergency food to a few relatively low-income families.

In recent months, however, volunteers at the agency have spent much of their time responding to a dramatic increase in requests for food from middle-income families suddenly facing hard times because a wife or husband lost a job. Usually the agency meets these requests by depositing bags of groceries on doorsteps. Now, for the first time, according to the volunteers, people are refusing help when they learn that the food is delivered to their doors and they cannot pick it up themselves.

"I'm still bothered by one man in particular," said Asneath McKnight, a volunteer at the agency. "He really needed food for his family. But it was a good address. He didn't want people to drive up."

"The thought of having everyone see they're having so many personal difficulties is a trauma," said Marilyn Schachter, records chairman for Bethesda-Help, who stressed that drivers try to be inconspicuous when delivering food.

The agency gave food to 456 Bethesda residents in 1982, an increase of 162 from 1981, and 288 more people than in 1980. "Before we didn't pay too much attention to food requests and it was somewhat haphazard," Schachter said. "But there's a very, very obvious change in what used to be. I don't have to read the newspapers to know how bad it is. I just read our requests."