Walmart has a new labeling program for its healthy foods called "Great for You."

The symbol should help many shoppers choose healthier foods and should encourage some companies, starting with Walmart, to improve their products, industry watchers say.

 Walmart’s program does an excellent job of highlighting healthful foods in many food categories, but it is not foolproof, says the Washington D.C.-based Center for Science in the Public Interest, a group that's often critical of American food products.

  The group says some distinctly not-great-for-you foods qualify for Walmart's symbol: cholesterol-rich eggs, salty canned vegetables, salt-water-injected fresh meat and poultry, nutrient-poor apple and grape juice, and grain foods that contain much more refined white flour than whole grain.

For its part, the big box retailer says the green and white "Great for You" symbol is part of a  healthier food initiative it launched a year ago.

“Today’s announcement by Walmart is yet another step toward ensuring that our kids are given the chance to grow up healthy,” First Lady Michelle Obama said in a prepared statement.

“Just over a year ago, Walmart committed to save shoppers a billion dollars in their cost of fruits and vegetables and the fact that Walmart exceeded this number is a real accomplishment and a milestone in our efforts to support families eating better.

"In addition, the healthy seal will be another tool for parents to identify the best products for their kids. Giving parents the information they need to make healthy choices is a key piece of solving childhood obesity.”

The company says the items with the “Great For You” icon must meet nutrition criteria from the 2010 Dietary Guidelines for Americans, U.S. Food and Drug Administration (FDA), U.S. Department of Agriculture (USDA) and Institute of Medicine (IOM).