Companies that make some of America's favorite baked goods, microwave popcorn and frozen pizzas may soon be under pressure from the Food and Drug Administration to make those foods more healthful.
The message from many of those foodmakers is, We're trying but not completely there yet.
"We've actually been working on this for many years," Campbell Soup spokesperson Carla Burigatto said in an interview. "The vast majority of our portfolio is labeled zero grams transfat."
For example, she said, the company's Pepperidge Farm Goldfish removed its partially hydrogenated fat about a decade ago.
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The rush is on after the FDA announced that it had made a preliminary determination that partially hydrogenated oils are no longer "generally recognized as safe" in processed foods. It will open a 60-day comment period before issuing a ban.
Since 2006, the agency has required food companies to include transfat content on nutritional labels. The fats are often found in cakes, cookies and pies; prepared icings; microwave popcorn; frozen pizza; margarine and other spreads; and refrigerator-dough products. A label listing partially hydrogenated oil indicates that transfat is present.
"Providing consumers with high-quality, great-tasting products is a priority for us," Mondelēz said in a statement. The company once faced a lawsuit before removing the transfat from its Nabisco-brand Oreo cookies. "In our U.S. product portfolio, all of our cookies and crackers are labeled as 'zero grams transfat' per serving."
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Several companies issued similar statements in response to the FDA plan.
"General Mills will be very responsive to this new request for comment from the FDA. Partially hydrogenated oil (PHO) has always been considered safe for use by FDA, and by the food industry as well. This is a major development. ... " the company said in a statement sent to CNBC.
"General Mills had already been working quickly to reduce the use of PHOs in products as the science began to shift on transfats—and more than 90 percent of our U.S. retail products are already labeled as zero grams transfat. But we will also need to move to respond quickly to FDA on this question, and we will."
Nestlé echoed that sentiment.
"We fully support the efforts of the FDA to improve public health," Nestlé spokeswoman Hannah Coan said in a statement. "The large majority of Nestlé foods and beverages do not contain partially hydrogenated oils (added transfats) as we have been actively working to remove them from our foods. We have made good progress and will continue our journey to remove all remaining partially hydrogenated oils."
Tyson Foods said it changed cooking oils in 2007 to remove transfats from breaded poultry products.
"This was done with an eye toward zero impact on taste or texture," Tyson spokeswoman Krista Cupp said in a statement to CNBC. "While Tyson chicken products are naturally low in transfat, it can be found in certain added ingredients such as cooking oils, which led to the reformulation of the company's breaded poultry portfolio."
Hormel also said it was close to the target.
"As many of our products are protein-based pork and turkey items, more than 97 percent of our branded retail portfolio does not contain partially hydrogenated oils. ... During the past few years we have been working with our suppliers to further eliminate PHOs from the few remaining products that contain them," Hormel said in a statement.
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Those efforts are the norm for the industry, according to a statement from the Grocery Manufacturers Association, which represents more than 300 businesses in the consumer packaged goods industry and related fields.
"Since 2005, food manufacturers have voluntarily lowered the amounts of transfats in their food products by over 73 percent," the group's statement said. "Consumers can be confident that their food is safe, and we look forward to working with the FDA to better understand their concerns and how our industry can better serve consumers."
The same is true for of restaurant companies, which have followed the transfat-free trend over the past several years.
"The restaurant industry is committed to taking a proactive role in addressing today's food and healthy living challenges as evidenced by the tremendous strides the industry has voluntarily taken to reduce or eliminate artificial transfats from menu items," said Joan McGlockton, vice president of industry affairs and food policy for the National Restaurant Association.
New York City Mayor Michael Bloomberg issued a statement Thursday pointing out he was the first to enact such a ban.
"Seven years ago we became the first city in the nation to prohibit restaurants from using transfats. Since then, at least 15 states and localities have followed suit and banned transfats—and more than 10 fast-food chains have eliminated transfats entirely," he said. "Today, we're greatly encouraged that the FDA proposed measures that would virtually eliminate the artery-clogging and unnecessary ingredient from our nation's food supply."
Bloomberg's health commissioner at the time, Dr. Thomas Frieden, is now the director of the Centers for Disease Control and Prevention.
—By CNBC's Amy Langfield. Follow her on Twitter at @AmyLangfield.