In 2019, as the COVID pandemic set in, photographer David McLain and I hatched the idea of searching for an American blue-zones diet. Thinking that our great-grandparents may have eaten similarly to people in the original blue zones, we searched for dietary surveys conducted in the early 1900s. To our dismay, we found that our own ancestors (who immigrated from northern and central Europe) brought their cows, pigs, and pickles with them.

Determined to find what food traditions other cultures, Indigenous and immigrant, had brought to the American table, we crisscrossed the country to find people who could tell us about these foods.

Here’s what we discovered: There is another American diet, one that could actually increase your life expectancy by up to 10 years and, in some cases, reverse disease. It’s not a fad diet invented by a South Beach doctor, a paleo diet marketer, or a social media influencer. This diet was developed by ordinary Americans, is widely affordable, is sustainable, and has a lower carbon footprint than a meat-heavy diet. Most important, it is hearty and delicious, developed over centuries by fusing flavors from the Old and New Worlds in ingenious and uniquely American ways

We start in New England, looking at the traditional foods of the Wampanoag Native Americans. Their ancestors played a role in history in 1621 when they encountered recently arrived colonists. One man, Tisquantum, taught colonists how to plant corn, a local food. Carolyn Wynne, a Mashpee Wampanoag elder and Otter Clan mother, and her friend, food anthropologist Paula Marcoux, re-create an early 17th-century meal for us using typical Wampanoag foods.

As Wynne cooks over an open fire, she seems to be impervious to the heat. In the coals, she roasts squash stuffed with hazelnuts, dried blueberries, and maple syrup. In a pot off to the side, she boils nasaump, a cornmeal soup. In a third pot, she poaches pumpkin slices in sassafras tea. Though the Wampanoag hunted game and collected mussels and oysters, 70 percent of their diet came from plant sources.

Marcoux tends cast-iron pots hanging over another fire. In one, there is bubbling msíckquatash, a Wampanoag staple stew of hominy, beans, and squash, which Marcoux gussies up with green beans, onions, and herbs. The Wampanoag might also add Jerusalem artichokes, acorns, chestnuts, and walnuts (the nuts sometimes powdered to serve as thickeners). “My particular obsession with history affords me the fun of networking with long-dead cooks in their long-gone kitchens through archival and archaeological sources,” Marcoux says. “It’s a thrilling privilege to conjure their wisdom through fire.”

On the other side of the United States, at the northern tip of Hawaii’s Big Island, we see another version of Native ingenuity on the farm where Scott Harrison’s family has been cultivating native plants for three generations. It abounds with produce eaten here for hundreds of years: sweet potatoes, bananas, pineapples, papayas, mangoes, and breadfruits. In a neatly tended patch, Harrison reaches into the shallow water and extracts a taro plant, holding it up like a trophy: “You can eat the leaves like spinach and boil the stalks like asparagus,” he says. “Mostly we survived off of the root, which we mash into a paste that we eat every day.”

To the west, on the island of Oahu, in suburban Honolulu, 95-year-old Ruth Chang is preparing lunch. “I cook every day,” she tells me as she minces root vegetables. “Once you stop, you lose it.”

Chang’s demographic may be the longest-lived on Earth. Chinese American women living in Hawaii enjoy about 90 years of life expectancy, and the diet of Chinese Americans living there supports such longevity. (Want to live longer? Influence your genes.)

Since Southeast Asians began arriving in Hawaii over 170 years ago as agricultural workers, each ethnic group has introduced its own flavors and ingredients. The Chinese brought leafy cabbage, soybean products, and teas. The Japanese, miso and their own version of tofu. The Filipinos, tender tips of many plants such as squash and pumpkin. This melding of foods and cooking techniques has made Hawaii the place to experience Asian fusion cuisine that’s primarily plant based.

African Americans living in the Deep South have a long tradition of eating blue-zones-type foods. What began as a largely plant-based West African diet morphed with local Native American and European influences to produce a unique and vividly delicious cuisine. Dietary surveys going back to the 1890s indicate that most foods eaten by southern African Americans were vegetables and grains. Aside from salt pork added for flavor, animal products played a minor role.

On a steamy morning in Charleston, South Carolina, we’re in chef-historian BJ Dennis’s home, huddled around a pot of okra soup. Okra, garlic, onion, butter beans, tomato, thyme, searingly hot Scotch bonnet peppers, and the splendid funk of fermented benne (sesame) seeds fuse New and Old World flavors. My first bite delivers a tsunami of umami followed by eye-watering heat and a blush of pure happiness. (These are the world’s happiest places.)

Dennis is on a mission to bring back the cuisine of his rice-growing ancestors. Captured from places such as Senegal and Liberia, his forebears were brought to the Low Country of South Carolina and Georgia to cultivate Carolina Gold rice. Because of their expertise, some of the enslaved Africans were allowed gardens where they grew African staples and local ingredients. “We took the rustic soul of the Africans and the Native American techniques and made this special mash-up,” says Dennis.

The traditional West African diet consisted mostly of greens, root vegetables, black-eyed peas, okra, benne seeds, herbs and spices, and cereals like millet; meat was eaten only occasionally. When captured Africans were shipped to America, the plants and seeds of their homeland foods came with them. They entered into cultural exchanges with Native Americans, who shared some similar farming practices and food staples; both cooked with corn, sweet potatoes, and local bean varieties. The result was a blended, innovative cuisine.

On another day, in Texas, we’re with chef-historian Adán Medrano as he destroys the myth of Tex-Mex cooking. In his Houston kitchen he stirs a savory posole in one pot and in another a tomato-stewed rice, both dishes flavored with the Texas Mexican trio of garlic, cumin, and black pepper.

“Greasy, cheesy Tex-Mex food was largely an Anglo invention,” Medrano tells me. “Our traditional enchiladas were not slathered with cheese. We fill ours with carrots and potatoes.”

Born in San Antonio, in south-central Texas, Medrano, 74, grew up eating cactus, beans, corn, chilies, potatoes, onions, mushrooms, portulaca, amaranth, various berries, and occasionally game. These were the authentic foods of Texas Mexican cuisine, a far cry from Tex-Mex culinary corruptions like chicken fajitas or extra cheesy quesadillas. These types of whole, plant-based foods are also typical of other Latin American cuisines.

As we traveled the United States, we found the historical diets of these Indigenous and immigrant cultures being interpreted by a new guard of chefs and food pioneers. As they re-create traditional dishes, they are not only opening a treasure trove of largely overlooked culinary genius but also offering new expressions of the standard American diets—which may actually help us get that extra 10 years.