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• In stating it has “no questions,” FDA accepts expert panel’s unanimous conclusion that Impossible Foods key ingredient is safe to eat 

• Impossible Foods welcomes the FDA’s publication of test data for public review 

• Now available in nearly 3,000 locations, the Impossible Burger will continue to be sold in restaurants, corporate canteens, universities and other foodservice locations in the United States and Hong Kong. 

REDWOOD CITY, Calif., July 23, 2018 —Impossible Foods has received a no-questions letter from the US Food and Drug Administration, accepting the unanimous conclusion of a panel of food-safety experts that its key ingredient is safe to eat. 

Impossible Foods makes meat directly from plants -- with a much smaller environmental footprint than meat from animals. The company uses modern science and technology to create wholesome and nutritious food, restore natural ecosystems and feed a growing population sustainably. 

The company’s flagship product, the Impossible Burger, is available in nearly 3,000 locations in the United States and Hong Kong. It’s the only plant-based burger featured in America’s most beloved “better burger” concepts Fatburger, Umami Burger, Hopdoddy, The Counter, and B Spot (the Midwest burger restaurant owned by Chef Michael Symon); earlier this year, America’s original fast-food restaurant, White Castle, added the Impossible Slider to menus in 140 restaurants nationwide. 


The Impossible Burger is made through a combination of plant-based ingredients. A key ingredient is “soy leghemoglobin.” Soy leghemoglobin is a protein that carries “heme,” an iron-containing molecule that occurs naturally in every animal and plant. Heme is the “magic ingredient” that enables the Impossible Burger to satisfy meat lovers’ cravings. 

Before issuing its no-questions letter, the FDA reviewed comprehensive test data about soy leghemoglobin to assess its status as “generally recognized as safe,” or GRAS. As standard process, the FDA posted the full, 1,066-page submission from Impossible Foods on its website for public review. FDA researchers also reviewed the comments of top food safety experts, who unanimously concluded multiple times that soy leghemoglobin is safe to eat and compliant with all federal food-safety regulations. 

“We have no questions at this time regarding Impossible Foods’ conclusion that soy leghemoglobin preparation is GRAS under its intended conditions of use to optimize flavor in ground beef analogue products intended to be cooked,” the FDA stated. 

“Getting a no-questions letter goes above and beyond our strict compliance to all federal food-safety regulations,” explained Impossible Foods CEO and Founder Dr. Patrick O. Brown, also Professor Emeritus of Biochemistry at Stanford University. “We have prioritized safety and transparency from day one, and they will always be core elements of our company culture.” 

In issuing the no-questions letter, the FDA also noted that soy leghemoglobin could be considered a “color additive” in some potential future applications. The FDA has a separate regulatory process to approve the use of food additives specifically for color, and Impossible Foods is preparing to engage in that process to ensure it has maximum flexibility as its products and business continue to evolve. 


Heme is an essential molecular building block of life, one of nature’s most ubiquitous molecules. It is most familiar as the molecule that carries oxygen in your blood. 

Heme is in virtually all the food we eat, and it’s particularly abundant in animal muscle. It’s the abundance of heme that makes meat (both meat from animal carcasses and Impossible Foods’ meat from plants) uniquely delicious and craveable. Heme is not just safe to eat - it’s required for life. 

To satisfy the global demand for meat at a fraction of the environmental impact, Impossible Foods developed a far more sustainable, scalable and affordable way to make heme and therefore meat, without the catastrophic environmental impact of livestock. The company genetically engineers and ferments yeast to produce a heme protein naturally found in plants, called soy leghemoglobin. 

The heme in the Impossible Burger is identical to the essential heme humans have been consuming for hundreds of thousands of years in meat — and while the Impossible Burger delivers all the craveable depth of beef, it uses far fewer resources. 

Producing the Impossible Burger uses about 75% less water, generates about 87% less greenhouse gases and requires around 95% less land than conventional ground beef from cows. 


Impossible Foods has prioritized safety and transparency since the company’s founding, and the Impossible Burger has complied with all food-safety regulations since before it was available to the public. 

In 2014, years before the company began selling product to restaurants, a panel of leading food safety experts gave the opinion that the Impossible Burger’s key ingredient, soy leghemoglobin, is “generally recognized as safe.” GRAS means a food is safe to be consumed under US regulations. 

Additional testing -- including a stringent rat feeding study -- provided even more objective, scientific data that the product is safe. A 2016 study examined whether consumption of soy leghemoglobin in amounts orders of magnitude above normal dietary exposure would produce any adverse effects. There were none. And a comprehensive search of allergen databases found that soy leghemoglobin has a very low risk of allergenicity, and it’s shown no adverse effects in exhaustive testing. 

In August 2017 the same panel of food safety experts reviewed the additional data we provided and again unanimously concluded that soy leghemoglobin was safe. In fact, the panel concluded that the new data further strengthened the safety case. In October 2017, Impossible Foods filed this additional new information with the FDA in a 1,066-page submission. Having reviewed that new safety information, the FDA declared today that it now has no questions regarding the safety of soy leghemoglobin in the Impossible Burger. 


Based in Redwood City, Calif., Impossible Foods makes delicious, nutritious meat and dairy products directly from plants -- with a much smaller environmental footprint than foods from animals. The privately held company was founded in 2011 by Patrick O. Brown, M.D., Ph.D., Professor Emeritus of Biochemistry at Stanford University and a former Howard Hughes Medical Institute investigator. Investors include Khosla Ventures, Bill Gates, Google Ventures, Horizons Ventures, UBS, Viking Global Investors, Temasek and Open Philanthropy Project. 

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Media Contact: Impossible Foods: Jessica Appelgren, [email protected] 

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