In Yorktown, the north Philadelphia neighborhood where Jenette Waller has lived for 41 years, the supermarkets are long gone.

"We had butcher shops, we had supermarkets, we had corner grocery stores, and you could walk to them," the great-grandmother, 69, said. "Now there's nothing to walk to."

Close by, there are only small stores with staples and a few processed and canned goods. Waller's favorite supermarket, large and well-stocked, is across town in south Philadelphia. It can be an all-day affair by bus, so Waller considers herself lucky that she is healthy and able to drive.

But things are about to change thanks to a statewide push to bring major supermarkets to underserved cities and rural villages. A local chain plans to open a new market in Waller's neighborhood next year. Not only will it bring jobs, but local officials hope it will eventually lead to better health.

Research shows higher rates of diet-related illnesses in communities with a dearth of supermarkets. A 2002 survey of health and economic data by a Philadelphia-based advocacy group, the Food Trust, found that people living in lower-income neighborhoods had disproportionately high rates of diabetes, heart disease and cancer. Obesity, malnutrition and diabetes also are more common in low-income children than their affluent counterparts, the report said.

Other studies have found similar scenarios from Washington to Los Angeles. Factors including access to health care also play a big role -- but the food connection is clear, said Hanna Burton of the Food Trust, which works to improve access to fresher, higher-quality food.

"The demand is so substantial and not just for supermarkets, but smaller grocery stores like corner stores," she said. Being able to buy better food raises chances that residents will improve their nutrition.

People living in areas without supermarkets eat more fast food and junk food from convenience stores, studies have shown.

In Philadelphia, the problem is acute: The Food Trust reported in 2002 that although the city's poverty rate is similar to other large cities, it had the second-lowest number of supermarkets per capita nationwide.

Boston was at the bottom of the list at the time of the survey, but an aggressive effort has since brought about two dozen new or expanded supermarkets to that city.

In Baltimore, the number of supermarkets has fallen and the number of diet-related ailments has risen over the past 15 years. In response, the Baltimore Healthy Stores initiative will bring better food to two of Baltimore's poorest neighborhoods.

The initiative is modeled after earlier work on Apache reservations in Arizona. Preliminary results there indicated that people with easier access to fruits, vegetables and other healthful fare will buy it, said Joel Gittelsohn, one of those spearheading the effort.

Store owners "have told us, 'We stock what people buy,' and often that is very junky stuff," he said.

Getting nutritious food to inner cities is not easy, but Philadelphia and Pennsylvania officials are working on ways to lure retailers.

The one-year-old statewide consortium, the Fresh Food Financing Initiative, helped entice the local chain, the Fresh Grocer, to come to Waller's neighborhood. It will set up shop in historic Progress Plaza, one of the nation's first black-owned shopping centers.

"It's a challenge, but we enjoy a challenge and we enjoy the city," said Pat Burns, president of the Fresh Grocer. The mix of products in each store varies, depending on the communities' ethnic makeup and spending levels, he said.

The previous supermarket left in 1998 and now Waller's closest small market is about eight blocks away. The staff is friendly and the store is well-kept, but its variety is limited.

"I try to get enough at the supermarket to last me for the month, but things like milk and bread you can't buy in bulk," she said, placing one of each in her cart, along with a head of iceberg lettuce. "That's when I come here, for perishables."

Many of Yorktown's 3,200 residents are financially secure, longtime homeowners, and many are older. They feel unsafe as they traverse potentially dangerous blocks to get to neighborhood corner stores, Waller said.

Officials hope that as many as a dozen supermarkets could open in the Philadelphia area within the next three years and work is under way to bring markets to underserved rural sections and parts of Pittsburgh, Burton said.

The Food Trust has paired up with a market research firm to spotlight the moneymaking potential in several underserved areas.

"Now we're having conversations [with companies] that will bring 10 to 12 new supermarkets in the area over the next one to three years," Burton said. "A lot of them will be in neighborhoods that were not being looked at a few years ago."

Customers shop at the Fresh Grocer, which will open a store in north Philadelphia to improve residents' food options.