The power of peanut butter

Fried peanut butter and banana sandwiches, Fluffernutters, peanut butter cups, and good old PB&Js are legendary creations. But other pairings abound; ask around, and you might hear people swear by peanut butter and tomato, or bologna, or onion, or even sardines.

''Peanut butter is a very personal food," says Lee Zalben, owner of Peanut Butter & Company, a Manhattan sandwich shop that specializes in such variations as the Pregnant Lady, a PB&P (pickle) sandwich, based on a customer's request, or the fried PB&B&B (bacon and banana) associated with Elvis Presley.

In the hundred-plus years since it entered our culinary mainstream, Americans have relied on peanut butter as an inexpensive, versatile, and tasty protein source. Today, peanut butter is everywhere. It flavors cookies, candy, ice cream, and cereal. It's spread on toast at breakfast, in sandwiches at lunch, on apples or celery for snacks; stirred into sauces, soups, and marinades for dinner; and baked into desserts. Despite modern concerns about fat content and peanut allergies, peanut butter remains an American staple, found in more than 75 percent of American households.

Children and peanut butter have long had a close association, writes Andy Smith in his 2002 book, ''Peanuts: The Illustrious History of the Goober Pea." The invention of sliced bread in the late 1920s, Smith writes, made peanut butter sandwiches easy for children to assemble themselves, as peanut butter continued to be low-cost and widely available. PB&J remains a popular lunch for kids and presents a challenge in schools, where peanut allergies threaten a small segment of the population.

In Boston Public Schools, nutrition education coordinator Debra Korzec-Ramirez says that individual schools make their own allergy-related decisions. If the school has a higher percentage of allergic students, ''the principal can request to be a non-peanut school," Korzec-Ramirez said. Often schools will designate peanut-free rooms for allergic students. And although the nutritionist has seen an increase in peanut allergies in her 10 years on the job, peanut butter remains popular among students.

''It's a tough one -- kids really like it," Korzec-Ramirez said. In a 59,800-student school system where roughly six peanut allergy attacks occur per year, peanut butter's broad appeal is ''why we haven't gone peanut-free like some of the smaller school districts," she said.

And though we often tend to think of peanut butter as kids' food, most people don't seem to outgrow their taste for the stuff. ''Most of us ate peanut butter sandwiches throughout childhood, and as we grew up, it was one of the first things we made for ourselves," says Zalben at Peanut Butter & Company. His forthcoming ''Peanut Butter & Company Cookbook" is full of recipes for sandwiches, savory entrees, breakfast items, and desserts.

Most of Zalben's recipes, such as peanut butter caramel cheesecake and peanut butter and jelly cupcakes, smother peanut butter's healthier qualities. But while the high fat content makes peanut butter a natural candidate for desserts, the fats are unsaturated, and it's also full of protein, so it can be a healthy and satisfying food to include in your diet, says Boston University nutrition professor Joan Salge Blake.

''Healthy fats can displace other foods that are high in calories but less nutritious," she says. Since fat helps food stay in the stomach longer, she says, you're more satisfied for a longer period of time. Salge Blake recommends eating peanut butter on whole grain toast for breakfast. ''It can take you through the morning," she said, and pointed out that eating peanut butter with apples or celery and raisins for a snack is a great way to increase fruit and vegetable intake. ''Peanut butter is wonderful. You save time, you save money, and you get good nutrition."

Just as long as you curb your Elvis cravings, which sometimes can't be helped.