Almost a third of the nation's 19.5 million elderly households don't have enough money for food, clothing and medical insurance because their housing costs are more than they can afford, a report says.

The study by the Gerontology Institute at the University of Massachusetts-Boston found the problem so acute for elderly in 3 million households "that even if their housing costs were to be reduced to zero, they still would be unable to meet their non-shelter needs at a minimum level of adequacy."These worst-off elderly are largely women - widows or never-married - living on minimum Social Security or welfare payments.

"Almost all their meager income goes to pay the rent," said Michael Stone, professor of community planning at UMass-Boston, who oversaw the study.

At the other end of the scale are elderly homeowners who have stable or even increasing incomes because their mortgages are paid.

The study found that 31 percent of U.S. elderly households are paying more than they can afford for housing.

Stone said his study did not track state-by-state or regional differences.

Although most of the nation's "shelter-poor elderly" are white, Stone said, generally lower incomes for minorities led almost half of elderly blacks and about 45 percent of the Hispanic elderly to fall into this category.

Stone suggested several policy proposals, including enabling the elderly to convert equity in their homes to cash, giving them property tax relief, encouraging shared living arrangements and increasing rent subsidies.