Eat more fruits and vegetables and less meat and fat? That's good advice today -- just as it was in 1917 when a poster was published by the U.S. Food Administration.

It is one of 80 food posters on display in an extraordinary exhibit, "Beans and Bullets and Of Course I Can," that opens this week at the U.S. Department of Agriculture. Independent curator Cory Bernat's goal was to study how, through printed posters and publicity, the government has tried to change dietary behavior. After all, as John Pardee, the chief of the Food Administration's publications, said with great irony in 1917, "All you have to do is induce the American people to change their ways of living -- that's all!"

Bernat, who assembled the exhibit as part of her master's history thesis, explores methods of communication such as messaging and graphic design, and how they changed over time. In World War I, before there was a radio in every home, the posters were text-heavy and packed with information. More than two decades later, they have a "Mad Men"-esque quality with colorful illustrations and emotional pitches geared to a nation of emerging consumers.

The transformation of food messaging is intriguing. But what's fascinating is the bluntness of the messages. Giving Americans advice about what to eat has become highly political: Even a common-sense suggestion that Americans eat more vegetables inevitably produces a backlash from egg, meat and dairy producers who don't want their products to get short shrift. The "eat more" tactic would not fly today.

Also interesting is that many of the posters promoted health advice that's in vogue today. One of them encouraged Americans to eat more cottage cheese, which the poster demonstrates has more protein per pound than beef, pork or chicken. Another promoted the benefits of eating locally. In a 1917 poster from the Connecticut Committee of Food Supply, a happy waiter with a potato head explains how potatoes are economical, patriotic, healthful and loyal: "Be loyal to Connecticut! Eat the potatoes the farmers have grown."

One poster even tried to make the now-fashionable connection between eating well and staying healthy: "Good eats, fewer doctor bills," trumpeted the Arizona Council of Defense.

In World War II, the posters looked different, but the messages were largely consistent. Rosie the Riveter-type women happily can vegetables with messages such as "Can All you Can" and "Of Course I Can!" (Where have you heard that lately?)

There were also posters encouraging women to carry their bags home from the grocery store (instead of having them delivered) to help the economy and the environment.

The discussion about how to -- or if we should -- change the way we eat is moving its way to the top of the news agenda. With more than one-third of American adults obese and 70 percent at risk of high blood pressure, public health advocates say it is an issue whose time has come. But often when reading, or indeed writing about it, it feels like a new subject. In fact, America has tried and succeeded before when crisis required it. As this exhibit shows, the messages are the same. The question is: Will Americans respond?

The exhibit is on display until Nov. 10. Check out the gallery online: www.