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First Lady Michelle Obama makes an announcement on Jan. 20, 2011 about Wal-Mart teaming up to bring consumers healthy foods for lower prices.

Walmart plans to gradually reduce the prices of healthy foods in its stores in conjunction with First Lady Michelle Obama's initiative to improve public health. On Thursday, company heads announced that they will sell items like fruits and vegetables at more affordable prices and reformulate their private label foods to reduce sodium, added sugar and fat in their products. Nutrition and public health expert Marion Nestle weighs in on the impact the mega chain could have on the food industry.