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URBANA, Ill. — Plant-based diets may provide plenty of positives for human health, but a new study finds beef still takes the cake when it comes to burgers. Research by a team at the University of Illinois, Urbana-Champaign reveals beef and pork burgers offer a more complete and digestible protein and amino acid profile than plant-based burger options.

Plenty of plant-based burgers claim to offer just as much protein as an old-fashioned beef or pork burger, but there’s more to the muscle-building story than simply counting grams of protein listed on the packaging. People often equate protein with muscle-building. It’s why those looking to build muscle eat tons of chicken and invest in post-workout protein shakes.

The reality of the situation is a bit more complex. Our muscles don’t need protein to grow, but they do need the essential amino acids found in protein. Different sources of protein offer different amino acids, and some are more helpful in terms of both concentration and digestibility than others.

To account for all this, the U.N.’s Food and Agriculture Organization (FAO) put together the digestible indispensable amino acid score (DIAAS) about 10 years ago. Now, study authors used the DIAAS to reach these new conclusions. Initially, the research team set out to better understand differences in protein quality among beef and pork burgers and plant-based burgers from Impossible™ and Beyond Meat®.

Per the FAO’s recommendations, the team used pigs during their experiments. The hogs were fed pork burgers, 80 percent and 93 percent lean beef burgers, the soy-based Impossible Burger, and a pea-based Beyond Burger. From there, scientists assessed the digestibility of each burger’s individual essential amino acids, using that data to determine final DIAAS values.

The best burger for all ages

Served without a bun, scientists call both the pork and beef burgers “excellent sources of protein” (DIAAS scores 100+, for people of all ages). Meanwhile, the team considers an Impossible Burger without a bun an excellent protein source, but only for people older than three. Finally, the study finds a bun-less, pea-based Beyond Burger is a “good source of protein” for people ages three and older.

“We have previously observed that animal proteins have greater DIAAS values than plant-based proteins and that is also what we observed in this experiment,” says Hans H. Stein, professor in the Department of Animal Sciences and the Division of Nutritional Sciences at Illinois, in a university release.

What about the bun?

Despite the findings, the public typically eats their burgers with a bun. So, researchers analyzed these scenarios as well. Grain products, however, offer low protein quality. Results show adding a bun leads to a lower DIAAS score for all burger types across the board. It’s important to note, though, that both beef and pork burgers still boasted 100+ DIAAS scores after accounting for the addition of a bun.

“There was a greater DIAAS value of mixing either the pork or beef burger with the bun – values of 107 and 105 respectively, for the over-3 age group – than there was for the Impossible Burger, which had a DIAAS value of 86 if consumed with the bun. That means you need to eat 15% more of the Impossible Burger- bun combination to get the same amount of digestible amino acids as if you eat the pork-based or the beef-based burgers. And if you have to eat more, that means you also get more calories,” says study co-author Mahesh Narayanan Nair, a professor at Colorado State University.

“It’s particularly children, teenagers, lactating women, and older people who are at risk of not getting enough amino acids. Results of this experiment, along with previous data, demonstrate the importance of getting animal-based proteins into diets to provide sufficient quantities of digestible essential amino acids to these populations,” Prof. Stein concludes.

“This is also really important in developing countries where there may be little access to animal-based proteins, particularly for children. In some countries, a majority of children are amino acid deprived. That’s extremely serious because, if children don’t get enough amino acids, their brain development can suffer. It’s especially important in those cases to design a strategy for getting high-quality proteins into diets for children.”

The study is published in the European Journal of Nutrition.

About John Anderer

Born blue in the face, John has been writing professionally for over a decade and covering the latest scientific research for StudyFinds since 2019. His work has been featured by Business Insider, Eat This Not That!, MSN, Ladders, and Yahoo!

Studies and abstracts can be confusing and awkwardly worded. He prides himself on making such content easy to read, understand, and apply to one’s everyday life.

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