Plant-based meat not nutritionally equivalent to real meat, finds study

‘Plant-based meat substitutes should not be seen as nutritionally interchangeable with real meat’

A vegetarian version of pad kra phao, using a meat substitute and stir-fried with basil and chili, served at a restaurant in Bangkok (AFP via Getty Images)

While plant-based meat substitutes can taste and chew similar to beef, scientists have found that the nutritional content of the two can “differ widely.”

The researchers from Duke University in the US believe the findings can help consumers make informed decisions as the meat products and plant-based substitutes are not “truly nutritionally interchangeable.”

Several studies in the past have urged countries to reduce their meat and diary production in order to stay within the safe limits for greenhouse gas emissions from cattle.

With years of push, complimented by large investments and sophisticated marketing, companies started producing plant-based alternatives to meat that they have claimed to be “indistinguishable” from their beefy counterparts.

In order to replicate the nutrition in meat, manufacturers add vitamin B12, zinc, and proteins from soy, peas and other plant sources, while also including leghemoglobin, an iron-carrying molecule from soy and red beet, and the fibre methyl cellulose, to simulate bloodiness and texture of beef, scientists explained.

However, their current study published in the journal Scientific Reports found that the two products “differ widely” from each other in terms of nutrition.

“To consumers reading nutritional labels, they may appear nutritionally interchangeable. But if you peek behind the curtain using metabolomics and look at expanded nutritional profiles, we found that there are large differences between meat and a plant-based meat alternative,” the study’s co-author Stephan van Vliet said in a statement.

In the research, scientists used a technique known as “metabolomics” to analyse the basic chemical components of the two types of meat, which helped determine how they are converted to energy and structural building blocks by the human body and its digestive system.

The researchers compared 18 samples of a popular plant-based meat alternative to an equal number of grass-fed ground beef samples from a ranch in Idaho.

When the scientists analysed the 36 carefully cooked patties, they found 171 out of the 190 chemical components, or metabolites they measured, varied between beef and the plant-based meat substitute.

The beef samples contained 22 metabolites that the plant substitute did not, while the plant-based meat contained 31 metabolites not found in the real meat, according to the study.

The scientists found that several metabolites known to be important to human health – such as creatine, spermine, anserine and the omega-3 fatty acid DHA – were found “either exclusively or in greater quantities” in beef.

Citing previously published studies, the scientists noted that these metabolites have potentially important anti-inflammatory and physiological roles that are important for the functioning of the brain and other organs like muscles.

“It is important for consumers to understand that these products should not be viewed as nutritionally interchangeable, but that’s not to say that one is better than the other. Plant and animal foods can be complementary, because they provide different nutrients,” Mr Van Vliet said.

“But some people on vegan diets (no animal products), can live healthy lives – that’s very clear,” he added.

The researchers called for further studies to determine whether there are short-term or long-term effects of the presence or absence of particular metabolites in meat and plant-based meat alternatives.