Area food banks are reporting a surge in requests for food from low-income residents over the summer and are having trouble meeting the demand.

"This is a national problem. We are all experiencing an increase in requests for food assistance as well as a decrease in donations," said Debra Alich, executive director of the Federation of Virginia Food Banks.

United Community Ministries, whose food pantry has served southeast Fairfax County since 1969, has been particularly affected. In June and July, the organization gave food to 700 more people than during the same period a year ago.

They are people such as Wofa Offeh, 54, of the county's Alexandria section, who undergoes kidney dialysis. The food stamps he gets each month only pay for a few items, such as bread, eggs and rice, so he depends on the food pantry at United Community Ministries' Fordson Road headquarters to help meet basic needs.

But the group's food supplies have been dwindling because of the increased demand. That means the bags of groceries Offeh takes home from the charity have been lighter. "Sometimes it's not enough," Offeh said.

United Community Ministries' clients get an average of two bags of groceries with a value of $20 to $25 each when they visit. The food is donated by churches, organizations and individual donors. About 75 people a day receive a total of 1,500 pounds of food.

Cheri Zeman, executive director of United Community Ministries, acknowledged that food stocks have been depleted. She and other area food bank officials said they were not sure why. The county has one of the nation's lowest unemployment rates among similarly sized counties.

"I think we're most perplexed by the fact that something is happening, and we can't quite put our finger on what it is," Zeman said.

After the Sept. 11, 2001, terrorist attacks, an economic downturn led to a rise in people asking for food.

"We knew what the cause was [then]," Zeman said. "But afterward, we were very shocked to see that the number of clients and new clients that we were seeing did not seem to subside."

Since the attacks, Zeman said, the number of individuals requesting emergency food assistance from United Community Ministries per month is up an average of 43 percent.

Agency officials, who have been issuing appeals for donations in recent weeks, are describing their predicament as a "crisis." The nonprofit organization has moved money from its other programs, such as child abuse and homelessness prevention, to pay for additional food.

The food shortage is not unique to United Community Ministries, said Tom Carroll, operations manager for the Virginia branch of the Capital Area Food Bank. Regionally, Carroll said, "the demand has gone up drastically in the last couple of months."

Though Carroll, too, was at a loss to explain the reasons for the increase, Alich blamed the economy, citing the latest census figure of 36 million people living in poverty nationally.

She said the grocery industry -- a top donor to food assistance programs -- has cut its aid. Although food retailers are "still very generous," Alich said, the industry "is crunching numbers like never before" to try to boost profits.

Another factor, Alich said, is that school-age children eat at least one more meal a day at home during the summer than they do during the school year.

Zeman noted that donations often drop in the summer because families are away on vacation. She suggested that donors bring a couple of extra bags of food or give money so that organizations can stretch dollars by buying groceries in bulk.