WASHINGTON – Oh, the irony. A nation full of overweight people is also full of label readers. Nearly 80 percent of Americans insist they check the labels on food at the grocery store.

They scan the little charts like careful dieters, looking for no-nos such as fat and calories and sugars.

Yet even when the label practically screams, “Don’t do it!” people drop the package into the cart anyway. At least that is what 44 percent of people admitted in a recent Associated Press-Ipsos poll.

So attentive, yet so overweight. Two-thirds of people in the United States weigh too much. Why, then, don’t labels make a difference? Why do people bother with them at all?

“I don’t know, force of habit. I want to see what I’m getting myself into,” said Loren Cook, 39, of Marysville, Wash. “It doesn’t make my buying decisions for me. It’s mostly a curiosity factor.”

He adds: “It’s got to taste good. Otherwise, there’s no point.”

The survey of 1,003 adults, conducted May 30 to June 1, found:

* Women check labels more frequently than men, 65 percent vs. 51 percent. Women also place more importance on nutrition content, 82 percent to 64 percent.

* Married men are more likely to check labels than unmarried men, by 76 percent to 65 percent.

* Younger people are more likely to look at calories on food labels. In the poll, 39 percent of people between age 18 and 29 said they look at calories first. Even so, 60 percent of younger people were more likely to buy foods that are bad for them even after they checked the label.

The poll has a margin of error of plus or minus 3 percentage points.

Are these avid label-readers really telling the truth?

People do exaggerate, said Robert Blendon, professor at Harvard’s School of Public Health. They tell pollsters they go to church and vote more often than they really do, he said.

He does believe most people do look at labels. They just do not use labels to lose weight, he said. Instead, diabetics use it to avoid sugars, or people with high blood pressure steer clear of sodium.

“It’s not being used as part of a total diet to really lower their weight,” Blendon said.

To help people lose weight, Blendon said, labels should state the number of calories in an entire package. Instead, labels list calories per serving, leaving shoppers to do the math.

The government is considering changes to packaged food labels to make them easier to understand.

Eye on food labels

The Associated Press recently polled 1,003 adults about food labels. Some of the findings:

* Six in 10 of those polled said they check food labels frequently. They are most likely to check for fats and calories.

* Eight in 10 said they find food labeling easy to understand.

* Three-fourths said they put a lot of importance on what they see on food labels.

* Almost one-half of those surveyed said they buy foods that are bad for them, even after they read the nutrition label.