This month, the Centers for Disease Control and Prevention issued a comprehensive nationwide behavioral study of fruit and vegetable consumption. Only 26 percent of the nation’s adults eat vegetables three or more times a day, it concluded. (And no, that does not include French fries.)

These results fell far short of health objectives set by the federal government a decade ago. The amount of vegetables Americans eat is less than half of what public health officials had hoped. Worse, it has barely budged since 2000.

“It is disappointing,” said Dr. Jennifer Foltz, a pediatrician who helped compile the report. She, like other public health officials dedicated to improving the American diet, concedes that perhaps simply telling people to eat more vegetables isn’t working.

“There is nothing you can say that will get people to eat more veggies,” said Harry Balzer, the chief industry analyst for the NPD Group, a market research company.