By Kathryn Strong

Is the plate half full or half empty?

The new food guide just unveiled by the U.S. Department of Agriculture recommends that Americans fill half their plates with fruits and vegetables. This advice - and the new, simple plate design, replacing the Food Pyramid - are significant steps forward.

But as a dietitian, I find myself focusing on the sharp contrast between the new icon and federal agricultural subsidies. The plate icon and the USDA's recently released dietary guidelines advise Americans to limit high-fat products such as meat and cheese. But the federal government continues to subsidize these very products with billions of tax dollars, and it gives almost no such support to fruits and vegetables.

The U.S. government spends about $16 billion per year on agricultural subsidies. And while more than 60 percent of agricultural subsidies in recent history have directly and indirectly supported meat and dairy production, fruits and vegetables have gotten less than 1 percent.

It's clear that the federal government understands that the latest nutrition research supports a shift toward plant-centered diets to help fight heart disease, cancer, obesity, and the other chronic diseases that are killing so many Americans. The dietary guidelines recommend eating more fruits, vegetables, and whole grains - and they even include sections outlining the benefits of vegetarian and vegan diets.

But the government is still having trouble putting its money where its mouth is.

It's an endless cycle. The government uses billions of tax dollars to encourage the production of foods that have been linked to chronic diseases, and it uses billions more to cover the resulting hospital bills. In 2008, medical costs associated with obesity added up to $147 billion.

Since the USDA's first Food Pyramid was introduced, two decades ago, obesity and diabetes have become commonplace. About 27 percent of young adults are now too overweight to qualify for military service, and an estimated one in three children born in 2000 will develop diabetes. More than 60 percent of deaths in the United States are caused by heart disease, cancer, and other diet-related diseases.

In 1991, the USDA unveiled the first Eating Right Pyramid, which emphasized grains, fruits, and vegetables, and reduced the emphasis on meat and dairy products. But it quickly withdrew the icon because of objections from the meat industry. The next year, the department introduced a similar food guide, but it added recommendations of two to three servings each day from the meat group and two to three from the dairy group.

The USDA is finally taking a bold step by introducing a guide that encourages a shift toward diets rich in plant foods. But just as the department has given its food icon a makeover, Congress must revamp farm policy to encourage the production and consumption of healthful foods. Our health depends on it.

Kathryn Strong is a staff dietitian for the Physicians Committee for Responsible Medicine. For more information, see www.pcrm.org. This was distributed by McClatchy-Tribune Information Services.