November 20, 2019 | 4 minute read

A new type of meatless burger is sweeping into restaurants and grocery stores across the country and creating a lot of buzz. The Impossible Burger and Beyond Burger are touted for tasting like actual meat, and also offering health benefits. But what’s really in these meatless burgers and can they fit into a healthy, cancer-protective diet? We asked the experts.

AICR research is clear that regularly eating too much red meat — and even small amounts of processed meats — increases the risk of colorectal cancer. That’s why one of AICR’s Recommendations for Cancer Prevention is to eat no more than 12-18 ounces of beef, pork and other red meats per week.

Another AICR recommendation is to eat a predominantly plant-based diet. Whole grains, vegetables and other plant foods are packed with dietary fiber, nutrients and phytochemicals. Evidence is clear that dietary fiber lowers colorectal cancer risk; studies point to other healthful compounds lowering risk of cancers. Plant foods can help people stay a healthy weight, which is one of the most important steps people can take to reduce the risk of many common cancers.

Heme, protein and other ingredients

Both meatless burgers contain plants as their protein source in place of beef. The Impossible Burger pulls its protein from soy and potatoes; Beyond Burger uses primarily pea protein. Both contain a lot of other ingredients as well, adding oils, binders, and flavorings.

AICR recommends choosing mostly whole and minimally processed foods. “That is not these patties,” says AICR’s Nutrition Consultant, Alice Bender, MS, RDN.

“Building an entirely new food — starting with extracting protein from plants — and then creating a substance with a meat-like texture using soy and potato protein, and adding oils and micronutrients appears to meet the definition of a highly processed food,” says Bender.

“We know that replacing red meat with foods like beans, vegetables and whole grains reduces cancer risk. But, we don’t know whether replacing red meat with one of these meat-tasting vegetarian burgers will have the same benefit.”

One of the key differences between the two brands of burgers is that the Impossible Burger adds heme iron to its mix. Our body needs iron to make healthy blood cells; heme is a type of iron found mainly in beef and other animals. Soybean roots are also packed with this iron. The Impossible Burger uses the soybean’s heme iron, producing it in large quantities by inserting it in yeast and letting the yeast ferment, which makes them — and the heme iron — multiply.

The manufacturers claim it’s the heme iron that gives their burgers a meaty texture, taste, and smell. (Beyond Burger uses beet juice extract for its red, meaty look.)

“Yet, heme iron is one of the candidates for why high amounts of beef and other red meats may cause cancer,” says Edward L. Giovannucci, MD, ScD, professor of nutrition and epidemiology at the Harvard School of Public Health and one of the expert panelists on AICR’s Continuous Update Project.

Treat them like red meat

“I don’t know that heme from soy products has been fully studied, and currently it is hard to say what the effects might be, especially if these are consumed frequently,” says Giovannucci.

“I would be concerned if people got a sense that since this is ‘plant-based,’ they can eat as much as they want. They may not get all of the benefits of what we generally consider as a whole food, plant-based diet.”

Giovannucci adds, “It is possible that approaches such as the Impossible Burger may turn out to be helpful, though we don’t yet fully understand what in red and processed meat is harmful.”

For now, like many foods, the bottom line is that moderation is key. “Until we understand how red meat increases cancer risk and if you choose to eat these burgers, treat them like red meat, limiting to no more than 12-18 ounces weekly,” says Bender.

If you’re looking for some tasty meat-free meals — yes, even burgers — you can find them in our Recipes section and sign up for Health-e-Recipe emails here.