“Hey, how about dinner?”

I had answered my cell phone in my car.

“Oh, I’ve already eaten,” I replied.

“Where did you eat?”

“In my car.”

“That’s sad.”

Now, every time I pull into a parking lot and brush the crumbs off before getting out of the car, I remember that conversation.

I plead guilty to the American way: eating as multitasking. The average person wolfs down more than 30 meals a year in the car, according to market researcher The NPD Group/NET. Almost one-fourth of all restaurant meals are ordered from behind the steering wheel.

Driving and dining may seem harmless enough. NOT!

Eighty percent of all car crashes are due to driver distraction, such as talking on the cell phone, fussing at the kids, applying makeup and, yes, eating. And those accident figures don’t include the nutritional train wreck that often results from four-wheel dining.

The problem, nutritionally speaking, is that there’s something very important missing from the car cuisine scenario: a plate.

“Fruits, vegetables, beans, peas and whole grains should take up two-thirds of the plate, and meat one-third of the plate,” says Leigh Anne Burns, nutritionist and registered dietitian at the Louisiana State University Health Sciences Center School of Medicine in New Orleans. “On the run, you get the reverse of that. You look for things you can hold on to, like sandwiches or wraps.” In other words, we use carbohydrates to turn our meals into hand foods.

With a plate, we also get a visual gauge of just how big our food portions are, says Burns.

And then there’s the time factor.

“If you are eating in your car, you are more than likely in a hurry,” says Julie Fortenberry, a sports and lifestyle nutritionist and registered dietitian at East Jefferson General Hospital in Metairie, La.

“It takes 20 minutes for your stomach to tell your brain that it’s full, that you’ve had enough. Fifteen minutes in the car won’t give you that time allowance,” says Burns.

What does allow that healthy clockwork to kick in is dinner conversation and putting one’s fork down to chew 20 times, she says.

“When you eat fast, you eat so quickly that you do not allow the taste buds on your tongue to recognize flavors, so you have a tendency to use more salt and sugar to get immediate satisfaction,” says Burns.

Adds Fortenberry, “If you are driving, you are concentrating on other things.” And this totally goes against the health concept of conscious eating.

So is the increase in drive-through eating really a reaction to the fact that we are so crunched for time?

“I think we use that as an excuse,” says Fortenberry, who says this is a universal complaint from clients. “When you think about it, how much time do you really NOT have? It’s an injustice if you don’t have 10 minutes to make something decent to eat.”

When you pull by a take-out window for a meal, “you are not in control of the calories. You don’t know how many hidden things are in there,” Fortenberry says.

Simply by making your own lunch when you make dinner, you can ensure – even if lunch is a sandwich – that you are using a whole-grain bread, a low-calorie or thinly layered spread, healthy greens and low-fat protein. And you are spending no more time making your healthful meal, and probably less, than you would spend waiting in that drive-through lane.

Planning meals ahead, Fortenberry says, makes all the difference for calorie-counters. By making your own instead of driving through, “You can cut the calories of a meal by half,” she says.

Catherine Aucoin knows the culinary dangers of the commuting life, where a 45-minute ride home is a daily temptation to eat in the car. She lives in Slidell, La., and drives to New Orleans to her job five days a week.

“I was sitting in the car, doing nothing, not thinking about what I was eating and eating things I wouldn’t eat if I were at home,” says Aucoin, who changed her eating habits after joining Weight Watchers in 2003.

She didn’t stop eating on that long commute after a day’s work when the hunger pangs kicked in, but she did change what she ate.

“I started eating fruit with a bottle of water,” says Aucoin, who prepared something as simple as washed grapes or sliced apples and put them in a plastic bag. “That would keep me satisfied until I could get home and prepare dinner.”

Although making a healthy meal to take on the road in lieu of taking time for a sit-down lunch may improve the quality of one’s nutrition, there are still some negative side effects to meals behind the wheel.

Eating at a table and treating food like an actual meal can improve digestion.

“You may not have as much acid buildup, you will chew slower, and you will let foods go down before you add more food on top,” Burns says. “And you’re less likely to drink a soda.” And less likely to have french fries.

Peter Walsh says weight control is about how we eat, where we eat and why we eat. The author of “Does This Clutter Make My Butt Look Big?” (Free Press, $25) says, “Diets are not about food; they are about decisions.” And when we base our food decisions on what we perceive to be time limitations, we are not only shortchanging our nutritional needs, but also sabotaging the life that most of us want.

Walsh preaches “mindful consumption.”

“It’s important to eat appropriately, to eat the appropriate foods and to do so in the appropriate amount of time. Can you really do this behind the wheel of a car?” says Walsh, who estimates that 60 percent of the money Americans spend on food is for food eaten outside the home. His book promotes such basic activities as eating with friends and family in a place that is happy and comfortable and being fully aware of the food that goes into your body.

“If you truly love food,” he writes, “then you should have respect for how and what you eat.”

Five things to consider before making your dashboard your dining table

– Car food equals hand food equals more carbohydrates in a meal.

– If your eye is on the road, your foot on the accelerator and your hands are on the wheel, your mind can’t be on nutrition.

– Car cuisine seldom has a plate, the universal measuring stick for food portion size.

– Healthy meals such as salads come with a knife and fork, something you can’t use if both hands are on the wheel.

– Saving time rarely saves calories.