Meat and meat substitutes are not nutritionally equivalent according to laboratory analysis
Plant-based meat substitutes have a taste and texture similar to real beef, and the 13 ingredients listed on their labels – vitamins, fats and proteins – seem to make them essentially equivalent to real meat.
But a more in-depth study by Duke University’s research team on the nutritional content of plant alternatives to meat, using a sophisticated scientific tool called metabolomics, shows that they are as different as plants and animals.
Meat substitute manufacturers are working hard to make the plant product as similar as possible to meat, including by adding legemoglobin, a molecule containing soy iron, and extracts of red beets, berries and carrots to mimic blood. The structure of the fake meat is compacted by adding indigestible fibers such as methyl cellulose. And to bring plant-based meat alternatives to protein levels in meat, they use isolated plant proteins from soy, peas and other plant sources. In some meat substitutes, vitamin B12 and zinc are also added to further reproduce the nutritional value of the meat.
But many other nutrients are missing from the labels and that’s where the products differ significantly from meat, according to a study published this week in Scientific Reports.
The metabolites that scientists measure are building blocks of the body’s biochemistry. They are crucial for energy conversion, the transmission of signals between cells, the construction of structures and their destruction, as well as many other functions. There are more than 100,000 such molecules in biology, and about half of the metabolites circulating in human blood are expected to come from what we eat.
“For consumers who read labels, they may seem nutritionally interchangeable,” said Stefan van Vliet (), a PhD student at the Duke University Institute of Molecular Physiology who leads the study. “But peeking behind the curtain with the help of metabolomics and looking at the expanded nutritional profiles, we found that there are big differences between meat and its plant-based alternatives.”
The Institute of Molecular Physiology’s main metabolic laboratory compares 18 samples of popular plant meats, an alternative to 18 beef samples from a ranch in Idaho. The analysis of 36 carefully prepared pies found that 171 of the 190 metabolites they measured were very different between beef and plant-based meat substitutes.
Beef contains 22 metabolites that are missing in plant substitutes. The plant substitute contains 31 metabolites that meat does not have. The biggest differences are observed in the amino acids, dipeptides, vitamins, phenols and the types of saturated and unsaturated fatty acids found in these products.
Several metabolites known to be important for human health have been found either exclusively or in much larger amounts in beef, including creatine, spermine, anserin, cysteamine, glucosamine, squalene and omega-3 fatty acids DHA. .
“These nutrients have potentially important physiological, anti-inflammatory or immunomodulatory roles,” the authors write in the article.
“These nutrients are important for our brain and other organs, including our muscles,” van Vliet said. “But some people on a vegan diet (without animal products) can also live a healthy life – that’s very clear.”
In addition, the plant-based meat alternative contains several beneficial metabolites that are not found in beef, such as phytosterols and phenols.
“It’s important for consumers to understand that these products shouldn’t be considered interchangeable, but that doesn’t mean one is better than the other,” said van Vliet, who describes himself as omnivorous and enjoys vegetarian food. , but also eats meat. “Plant and animal foods can be supplemented because they provide different nutrients.”
More research is needed to determine whether there are short-term or long-term effects from the presence or absence of certain metabolites in meat and plant alternatives to meat, the study authors recommend.
Reference: Stephan van Vliet et al, A metabolomics comparison of plant-based meat and grass-fed meat indicates large nutritional differences despite comparable Nutrition Facts panels, Scientific Reports (2021). DOI: 10.1038 / s41598-021-93100-3
Source: Lab analysis finds near-meat and meat are not nutritionally equivalent – Karl Leif Bates, Duke University School of Nursing