Walmart Inc. (NYSE:WMT) is preparing to remove synthetic dyes and about 30 other additives, such as certain preservatives, artificial sweeteners, and fat substitutes, from its U.S. private-label food lines. The change is one of the most extensive overhauls ever undertaken by a major retailer. The adjustments will affect brands like Great Value, Marketside, Freshness Guaranteed, and bettergoods. John Furner, president and CEO of Walmart U.S., said the company is acting on direct consumer feedback. “Our cust ...