Fast food isn’t the only thing. Jaeger snacks on hard-boiled eggs these days. Cymbala stopped taking along big chunks of meat after she choked on one while driving on the highway; she’s made the shift to sandwiches for long trips. And Lynne Molnar, 56, of Cambridge, ate oatmeal with nuts and fruit until a policeman pulled her over for a red-light violation (a judge overturned the ticket) and ordered her and her 11-year-old daughter, Caroline, to throw away their cereal. “That’s called littering,’’ Molnar told him pointedly.

“But once in a while, I would get a Frosty and that you just have to eat with a spoon!’’ says Jaeger. “Knees come in handy then . . . one hand for the cup, one hand for the spoon, and the knees for the steering wheel.’’

Kent Lam of Randolph, 30, likes bagels from Dunkin’ Donuts. Joan Jaeger, 58, of North Attleboro, used to go for burgers “because forks and spoons were tricky.

Not infrequently, that means eating, and for many of us, car fare is the stuff you pull up to a window to order. Seventy percent or more of the Dunkin’ Donuts shops in Massachusetts have drive-through windows; 50 to 60 percent of McDonald’s sales are made at drive-through windows, according to spokeswomen for the companies.

“People just get in the car and think, ‘I’ll do what I have to do,’ ’’ says Sergeant James Fitzpatrick of the Lowell Police Department’s traffic division.

But the study lists other distractions, including daydreaming, personal hygiene, and eating, each of which accounted for 2.1 percent of the total.

Few of us are strangers to dining and driving, as well as other, more distracting habits on the road. A 2006 study by the National Highway Traffic Safety Administration blamed “inattentive driving’’ for 80 percent of all car accidents and 65 percent of near-misses. Use of wireless devices accounted for 14.6 percent of the crashes, more than any other cause. Last month the Obama administration banned federal and military personnel from texting while driving.

Sound strange? It shouldn’t. Studies show that more people eat in their cars, more often, than ever before, according to Stephen Bailey of Tufts University, an associate professor of anthropology and nutrition - and the food we consider acceptable to eat while we’re driving has changed. Once we were a nation on wheels. We’re becoming a nation of meals on wheels.

Helen Cymbala, 54, who lives in Boxford, tells the story of a woman she saw sipping espresso from a tiny china cup while driving in Cambridge. “She had her pinkie finger up in the air,’’ Cymbala says, sounding amazed.

Northeastern University student Sam Maman, 19, keeps one hand on the wheel while the other holds a slice of pizza. “You can manage it,’’ says the Newton resident. “It’s hard to use the phone and the pizza and the car, though.’’

Carolyn Roesler, 45, of Plainfield, Vt., eats toast in her car while driving to work, even though “there’s always a possibility that you’ll show up with a few crumbs on your chest.’’

Emily Lapkin of Boston, 35, still eats in her Saab - “designed for Euros who would never dream of eating in their cars’’ - even though when she first started driving she had an accident while eating a quesadilla.

“The only thing worse than quesadillas [are] open-faced bagels with cream cheese,’’ she says. “I once tried this and a hand-over-hand turn resulted in cream cheese all over the steering wheel.’’ Since then, she has switched to supermarket sushi.

So why not sit down and eat later? Hunger, says Maman, the Northeastern student, who fuels up behind the wheel “usually for lunch or like a pre-dinner dinner.’’

No time, despite “every day a new chocolate stain on a freshly washed piece of clothing,’’ says a 65-year-old saleswoman who drives six hours a day and wouldn’t give her name for fear police might run her license. Last month the knee-steerer navigated through a tire blowout, “hot chocolate between my legs, cookie in my hand.’’

The need for energy, “some nutrition to make it through the remainder of my day,’’ says Joe Mastroianni, a tile-setter who’s in his 40s. “I live on Nantucket, and we don’t have fast food. But if I’m on the mainland, I’ll stop at Burger King.’’

Those reasons and more, according to the scientists.

“[Anthropologist] Mary Douglas said a long time ago that food is not feed,’’ says Bailey. But while dining once also meant socializing, “In the last 20 years or so there’s been this tendency to make eating simply stuffing your stomach. Basically what happened with fast food and eating in cars is, food has become feed again.’’

Bailey says people are time-starved; he also cites suburbanization and marketing as factors contributing to the trend.

“The popular theory is that we’re time-starved; we just don’t have enough time in the day,’’ he says. And that carries prestige: “When we’re multitasking, what we’re thinking about is how important we must be to have to do all these things all at once. . . . [And] the ultimate kind of multitasking is actually feeding yourself while you’re doing other stuff.’’

Suburbanization has meant longer commutes for many workers, and a study of truck drivers by Toyota found that has contributed to a view of the automobile as office and dining room. “People manage their lives out of their trucks, and I think that can be said for most automobiles nowadays,’’ Bailey says.

Then there’s marketing, which has widened our expectations about what we can eat in our cars, and made it easier to do so. The standardization of mass-marketed food (“every Big Mac is the same as every other Big Mac,’’ Bailey says) makes it simple to eat more than snacks while we’re driving. As Maman says, “You really don’t need to look at your food while you’re eating.’’

Bailey agrees. “You can eat it without thinking about it. Sandwiches and fries or chips and a drink and maybe a dessert of some kind - it isn’t very nutritious, but it is a whole meal.’’

And it’s one that he goes for himself. Asked if he also eats behind the wheel, the professor says, “Oh, God, yes.’’

“I can dissect this intellectually,’’ he says, “but I get sucked up by it.’’

© Copyright 2010 Globe Newspaper Company.