Plant-based burgers not healthier than beef, new research shows

By Lilian Schaer for Livestock Research Innovation Corporation

A plant-based burger might look like beef and taste like beef - but that doesn’t make it beef. According to new research from the University of Guelph, that’s an important distinction that has a dramatic impact on everything from how we digest plant-based protein alternatives to the type of bacteria growing in the human gut.

It also has consequences for overall human health, says Prof. Michael Rogers, a Tier Two Canada Research Chair in food nanotechnology and associate professor in the University of Guelph’s food science department who led the research.

“For the first time in history, 50 to 60% of the adult population are afflicted with at least one type of diet-related chronic disease, and we’re seeing an entirely new epidemic, which is metabolic syndrome,” says Rogers. “We see the prevalence of this syndrome, which includes obesity, high blood pressure and diabetes, increase whenever a population introduces new ultra-processed foods.”

Although there’s no one source of metabolic syndrome, Rogers believes what he calls the disturbing trend of displacing minimally processed foods with products that are ultra-processed to be a significant contributor to the problem. Ultra-processed foods are ones made from ingredients extracted from whole foods, formulated to be tasty, low cost, convenient and have a long shelf life.

“These foods do not resemble the whole foods they come from; the average Canadian today consumes 48% of their calories from ultra-processed foods that are higher in salt, sugar and saturated fats,” he says. “But it’s more than just the composition that’s changing, it’s also the impact those foods have on our bodies.”

To delve deeper into this issue, Rogers’ team conducted in-depth research to compare the body’s digestion of plant-based meat – in this case a Beyond Beef burger – and a burger made of real ground beef.

What Ph.D. candidate, Zhitong (Zoe) Zhou and Rogers found is that it is quicker and easier to digest a plant-based burger than a meat burger. This leads to rapid fat digestion and ultimately a higher lipemic index (equivalent to the glycemic index for carbohydrates).

Faster digestion and absorption of fats results in more lipids circulating before the body stores them  - an important biomarker for cardiovascular health. In addition to lipids, the plant-based burger contains significant amounts of starch, which is capable of increasing blood sugar levels. A meat patty contains no carbohydrates, so it doesn’t impact blood sugar levels.

“Meat is a complex protein network that entraps fat, so it takes the body longer to access and then digest or break down that fat. This releases nutrients more slowly into the body, potentially altering feelings of fullness for a longer period of time after eating,” explains Rogers. “When you formulate a plant-based burger, the fat can’t be bound the same way as it is in meat, so it breaks down more quickly. That’s a major limitation to current ultra-processed food technologies.”

The food industry has done a remarkable job of creating many processes to turn perishable whole food commodities into self-stable ingredients such as oils, starches and protein isolates. According to Rogers, more work needs to be done to take those ingredients and formulate them into ultra-processed foods that also resemble whole foods not just during consumption but also while they’re being digested.

The high starch or carbohydrate content in the plant-based burger also favours the growth of starch-fermenting bacteria early in the colon, the research found. Those bacteria metabolize the fat, creating changes in the populations of micro-organisms in the gut and in short-chain fatty acids. Consumption of plant-based burgers can lead to changes in the human gut microbiome, notes Rogers.

So, what’s the takeaway for the beef industry?

“People need to change their thinking around ultra-processed foods. Just because something is plant-based, doesn’t make it healthier,” Rogers says. “The body does not digest plant-based burgers in the same way as it does real beef, so the two products are not nutritionally the same. Labelling both as meat is entirely misleading.”

Part of the challenge is that only about two percent of Canadians are involved in farming – compared to a century ago when more than 60% of the population worked in agriculture – leaving most people with little understanding of food and how it is produced.

That lack of understanding of the value of whole foods spills over into environment and climate change issues as well. There is little appreciation for the key role that livestock play in carbon sequestration and being able to use land for food production that isn’t suitable for growing crops.

“A two-class food ecosystem is emerging in Canada, where only a subset of Canadians can afford the time and cost to follow Canada’s Food Guide recommendations to prepare meals from scratch and to avoid ultra-processed foods; this will become a problem for Canada moving forward,” Rogers says.

Rogers’ research was supported by Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery and Canada Research Chair Programs.

A webinar where Rogers presents his research in more depth is available on the Livestock Research Innovation Corporation website.

This article is provided by Livestock Research Innovation Corporation as part of its ongoing efforts to report on research developments and outcomes, and issues affecting the Canadian livestock industry. It was originally published in the February 2023 edition of Ontario Beef.