New peer-reviewed paper by more than 20 protein experts calls for rethinking dietary protein guidance beyond "eat more protein": National Pork Board reports

A newly published peer-reviewed paper in Critical Reviews in Food Science and Nutrition synthesizes findings from a February 2025 scientific workshop.¹* The paper, authored by more than 20 international protein researchers, critically examines 11 widely held propositions about dietary protein needs and benefits and concludes that in some instances, the science is simply insufficient or not robust enough to interpret as support for select propositions.  

What is this paper about? 

The paper, titled "Examining Widely Held Propositions on Human Dietary Protein Needs and Benefits,"¹ is the proceedings of a workshop designed to explore current beliefs about dietary protein. Expert authors reviewed evidence on protein quantity, protein quality, essential amino acid (EAA) adequacy, digestibility, satiety, aging, muscle mass, weight loss, chrononutrition, and protein leverage, rating the strength of evidence for each proposition on a formal scale. 

“Protein science has advanced significantly, but despite thousands of published studies, in some instances there is still a lack of publicly available quality data,” said Mitch Kanter, PhD, Principal, Mitch Kanter Health & Nutrition Insights and Adjunct Associate Professor at the University of Minnesota, first author on the paper and a primary organizer of the workshop. “The significance of this workshop was rooted to bring together the leading protein science experts to clarify what we know, identify what we still need to learn and encourage a more evidence-based discussion about dietary protein and human health.” 

What did the experts find? 

For most of the 11 propositions examined, experts concluded that full acceptance was not yet warranted based on available data, though many were rated as plausible and supported by preliminary evidence. Key findings include: 

• Protein quality matters as much as quantity. Protein foods differ in amino acid composition, digestibility, and bioavailability. The digestible indispensable amino acid score (DIAAS) is the recommended method for evaluating protein quality, and animal-sourced proteins generally rate higher than plant-sourced proteins. 

• Individual essential amino acids have distinct biological roles. Leucine, methionine, threonine, and the branched-chain amino acids (BCAAs) each affect specific metabolic pathways. Current Recommended Dietary Allowances (RDAs) for individual EAAs may underestimate true physiological needs for functions beyond basic protein synthesis. 

• Higher protein intake during weight loss is supported, but with nuance. Evidence suggests that protein intakes above the RDA (0.8 g/kg/day) can help preserve lean muscle mass during caloric restriction with most benefit observed when protein intake is maintained at habitual levels (expressed in g/kg/day) rather than simply increased in absolute grams. 

• Protein leverage is well-supported. There is strong experimental and observational evidence that humans prioritize protein intake, and that diets low in protein relative to fat and carbohydrates drive increased total calorie consumption — a mechanism potentially contributing to obesity. 

• Older adults likely need more protein than current guidelines recommend. Evidence suggests intakes of 1.2–1.6 g/kg/day or more may be needed to preserve muscle mass and function with aging. 

• High protein intake does not appear harmful to healthy kidneys. A systematic review of RCTs found no adverse kidney effects at intakes up to 1.5 g/kg/day or 20% of energy. 

• Protein may support fullness, but the science is more nuanced than common messaging suggests. While protein is widely viewed as a satiating nutrient and some studies show higher-protein diets can modestly increase fullness, experts concluded that current evidence does not firmly establish protein as uniquely or consistently the most satiating macronutrient. They noted that appetite is difficult to measure, that feelings of hunger or fullness do not always predict food intake in real-world settings, and that protein’s effects may depend on the food source, eating occasion, diet pattern and individual context. 

• Protein timing and distribution across the day shows early promise. Distributing protein more evenly across meals, particularly increasing protein at breakfast, may support muscle mass. 

• A threshold above which protein is harmful has not been established. The paper found no demonstrated adverse effects of protein intake above the RDA for healthy adults across several disease categories, including cardiovascular disease, type 2 diabetes, and sarcopenia. 

What other research on dietary protein does the paper call for? 

True scientific progress comes when experts are willing to examine assumptions, evaluate evidence carefully and identify where better data are needed. This paper identifies several priorities for future protein science: 

• Larger, longer randomized controlled trials with hard clinical endpoints (not just surrogate markers like muscle protein synthesis rates) 

• Better measurement tools for appetite and satiety 

• More data on protein needs across diverse populations, including children, adolescents, and people using GLP-1 receptor agonists for weight loss 

• Refined estimates of digestible and utilizable amino acid supply from mixed diets 

• Clearer distinction in guidance between protein quantity and protein quality 

Support for this investigation: National Pork Board  

As a collaborator in the workshop and co-author on this paper, National Pork Board Senior Director of Human Nutrition elaborates on how pork fits into the protein quality conversation. “The National Pork Board was proud to help support this important scientific workshop and contribute to the resulting publication,” said Kristen Hicks-Roof, PhD, RDN, LDN. “For pork, this work matters because it helps elevate the conversation from ‘more protein’ to ‘better protein’ guidance that considers protein quality, nutrient density, dietary patterns and how people actually eat. Pork has an important place in that conversation as a high-quality protein food that can support healthy, practical and enjoyable eating patterns.” 

Pork was used as a practical example in the workshop and proceedings paper of how protein foods can be evaluated not only by grams of protein, but also by amino acid adequacy, nutrient density, affordability, accessibility, cultural relevance and fit within healthy dietary patterns. Dr. Hicks-Roof adds that, “Pork fits into the protein quality conversation because it is a complete, high-quality protein food that provides all essential amino acids and contributes important nutrients, including thiamin, niacin, vitamin B6, vitamin B12, selenium, zinc, phosphorus and choline.”²  In addition, lean pork can help Americans meet nutrient needs as part of balanced, evidence-based dietary patterns.³  

As discussions about dietary protein evolve, pork offers a relevant example of a protein food that delivers both protein quantity and protein quality within meals that are accessible, versatile and familiar to many consumers. 

About the National Pork Board 

The National Pork Board has responsibility for Pork Checkoff-funded research, promotion and consumer information projects and for communicating with pork producers and the public. The Pork Checkoff funds national and state programs in consumer education and marketing, retail and foodservice marketing, export market promotion, production improvement, science and technology, swine health, pork safety, and environmental management and sustainability. For the past half century, the U.S. pork industry has delivered on its commitment to sustainable production and has made significant strides in reducing the environmental impact of pig farming. Through a legislative national Pork Checkoff, pork producers invest $0.35 for each $100 value of hogs sold. Importers of pork products contribute a like amount, based on a formula. For information on Checkoff-funded programs, pork producers can call the Pork Checkoff Service Center at 800-456-7675 or visit pork.org.  

REFERENCES: 

1. Kanter MM, et al. Examining widely held propositions on human dietary protein needs and benefits: a critical review of the science that shapes both the data and our understanding of an essential macronutrient. Critical Reviews in Food Science and Nutrition. Published online May 8, 2026. https://doi.org/10.1080/10408398.2026.2658728. 
2. Pork, fresh, loin, tenderloin, separable lean only, cooked, roasted. FoodData Central website. https://fdc.nal.usda.gov/food-details/168250/nutrients. Published April 1, 2019. Accessed May 15, 2026.  
3. Agarwal S, Fulgoni VL 3rd. Association of pork (all pork, fresh pork and processed pork) consumption with nutrient intakes and adequacy in US children (age 2-18 years) and adults (age 19+ years): NHANES 2011-2018 analysis. Nutrients. 2023;15(10):2293. 

*Support for the Dietary Protein Needs and Benefits workshop was provided by the following organizations: National Pork Board, Ajinomoto, Mars, Inc, Danone North America, National Cattlemen’s Beef Assn., The General Mills Company-Bell Institute of Health & Nutrition, American Egg Board-Egg Nutrition Center, National Dairy Council, International Flavors & Fragrances (IFF), Weight Watchers, Soy Nutrition Institute Global, Alliance for Potato Research & Education, (APRE) Dairy Council of California, Academy for Health & Lifespan Research, American Federation for Aging Research (AFAR), Glanbia Performance Nutrition, California Dairy Research Foundation, Science Unbound Foundation, Equii Foods. Personnel from the following organizations provided non-financial support in the preparation of the Appendix section of the manuscript: Danone North America, International Flavors & Fragrances, Marine Biologics, National Cattlemen’s Beef Assn, National Pork Board.