top of page
  • Real Pork Trust Consortium

In Healthy, Young Adults, Pork and Animal-Based Proteins Improve Essential Amino Acid Intake and Whole-Body Net Protein Balance

Pork as a source of protein, egg, steak, peanut butter, mixed nuts, and tofu
This 2021 study examined how consuming different types of protein influenced whole-body protein balance in healthy, young adults.

Dr. Nicholas Gabler, a Professor in Swine Nutrition in the Department of Animal Science at Iowa State University, summarized this 2021 peer-reviewed journal article by Sanghee Park and colleagues at the University of Arkansas and Gachon University in South Korea. This study examined how eating protein from animals, such as pork, compares to eating protein from plants when considering amino acids and net protein balance in healthy, young adults.

Major Finding

In healthy, young adults, animal-based protein sources (such as beef, pork, and eggs) resulted in greater anabolic whole-body net protein balance responses than plant-based protein sources (tofu, kidney beans, peanut butter, mixed nuts). Anabolic whole-body net protein balance responses measure how the body uses protein to build and maintain muscle mass.

In the study, animal protein sources increased protein synthesis (or building new protein in the body). When compared to plant protein sources, pork and eggs also slowed protein metabolism. The magnitude of these anabolic responses suggests that the body’s metabolism is responsive to the protein food source's essential amino acid (EAA) content. However, the calorie differences between protein sources need to be studied further.

For young, healthy adults, ounce equivalents of pork, egg, and beef protein food sources as defined by the Dietary Guidelines for Americans (DGAs) are utilized differently than plant proteins due to differing EAA content and bioavailability.


Why It Matters

In protein foods, EAA content and bioavailability are major contributors to protein quality and metabolism. While dietary protein is recognized as important in the DGAs, the Recommended Dietary Allowance (RDA) for protein can typically be met by most Western diets that meet calorie requirements without considering EAA content, bioavailability, or metabolism of protein sources.

In situations such as exercise training, aging, or recovery, higher EAA content or anabolic protein intake than the RDA may be optimal to support muscle maintenance, repair, and health. Lean pork provides EAA and can produce positive anabolic whole-body net protein balance responses.


How the Research Was Conducted

Researchers conducted an 8.5-hour metabolic study in 56 healthy young adults. Participants were divided into groups by gender and assigned to 1 of 7 food treatments: 1) 2 ounces of cooked beef sirloin, 2) 2 ounces of cooked pork loin, 3) 2 cooked eggs, 4) ½ cup of red kidney beans, 5) 2 tablespoons of peanut butter, 6) 4 ounces of tofu, and 7) 1 ounce of mixed nuts. The pork and beef were cooked to temperature in a skillet, and kidney beans were pre-cooked. Changes in isotope flux from baseline were assessed. After participants consumed different protein sources, researchers measured how isotopes changed in participants to assess their whole-body protein balance and then compared the changes between groups.


Learn More

To learn more about how animal-based proteins compare to plant-based proteins as healthy young adults seek to optimize their diets, read the full peer-reviewed journal article.

In healthy young adults, pork and animal-based proteins improve essential amino acid intak
Download • 212KB


bottom of page