Beyond the Protein Trend: The Science of Protein Quality, Utilization, and Muscle Health
Protein recommendations often focus on quantity and quality, but how protein is utilized by the body depends on much more. The food matrix, protein timing and distribution, physical activity, age, and other factors can all influence digestion, absorption, muscle protein synthesis, and metabolic health.
This webinar explores the science shaping protein recommendations and its practical implications including protein’s role in muscle health, satiety, weight management, and healthy aging. It also explores factors contributing to the protein utilization gap across key population groups and highlight opportunities to optimize protein intake, timing, and physical activity across
the lifespan.
This webinar brings together Sara Oikawa PhD, Chief Science Officer at Enhanced Medical Nutrition, and Dana Angelo White MS, RD, ATC, Nutrition & Fitness Consultant and Chef, for an evidence-based look at the evolving science of dietary protein and what it means for nutrition professionals.
- Protein Quality and Utilization
- Muscle Health Across the Lifespan
- Protein, Satiety and Weight Management
Presenters:
Ryan Nuccio, MS, RD
Associate Principal Scientist
PepsiCo Life Sciences
Sara Oikawa, PhD
Chief Science Officer
Enhanced Medical Nutrition
Dana Angelo White, MD, RD, ATC
Nutrition & Fitness Consultant and Chef
Dana White Nutrition, Inc
Funding from non-CPE revenue for CPE planning, development, review, and / or presentation has been provided by PepsiCo. The speakers received compensation from PepsiCo for their participation. Any opinions or scientific interpretations expressed in this presentation are those of the speakers and do not necessarily reflect the position or policy of PepsiCo, Inc.
Beyond The Protein Trend: The Science of Protein Quality, Utilization, and Muscle Health awards 1.25 CPEUs in accordance with the Commission on Dietetic Registration's CPEU Prior Approval Program.
Q&A
During the live webinar, the speakers received so many great questions—more than we had time to address. After watching the webinar recording above, check out these additional insights from our speakers in the bonus Q&A below.
Q: Does protein need to be consumed before resistance training, or is eating it afterwards just as effective?
Sara Oikawa: We don’t usually recommend that protein be consumed before exercise because it will sit in the stomach during exercise and could cause gastrointestinal distress. This is in contrast to easily digestible carbohydrates, which we recommend consuming before and during exercise to help fuel training. Since we are (in most cases) not using much, if any, protein for fuel during exercise, it does not need to be consumed beforehand. Consuming protein after exercise is very effective for supporting
muscle growth and repair as a result of the muscle adaptions to exercise (repair, growth, etc.). When we exercise, it sensitizes muscle to the muscle building effects of protein, meaning that protein is more effective when muscle has been exercised. This effect can last for hours after exercise, so it isn’t necessarily critical to consume protein immediately around the exercise event.
Q: Is 25–30 grams of protein per meal still a useful recommendation, and what does the evidence show?
Sara Oikawa: It is a great general recommendation to make things easy. However, as discussed in the webinar, the source of the 25-30 grams of protein is highly influential to its efficaciousness in supporting muscle health. For plant-based sources (ex. pea protein) this might be too low as levels of methionine, cysteine, and leucine would be low. If consuming a whey protein isolate, 25-30 g is likely sufficient if the leucine content is high enough (~3 g or greater). Recommendations from the literature are 0.24 g/kg per
serving for people aged 18-30 years, and 0.4 g/kg per serving for people aged 60+. If between the ages of 30 and 60, depending on how active you are and your dietary goals, I would recommend leaning closer to the 0.4 g/kg/serving.
Dana Angelo White: I agree with Sara and want to continue to highlight the importance of overall intake timing! If you can be consistent with intake throughout the day, counting every gram is probably not necessary. Meals with high-quality protein sources likely have 25-30 grams. This might require some extra intention at breakfast and making sure there are protein sources at snacks to help round out intake for the day.
Q: Why is leucine so important for muscle protein synthesis—and what should people know before focusing on it?
Sara Oikawa: Leucine, of all 9 essential amino acids can independently stimulate muscle protein synthesis (MPS). A study by Churchward Venne et al., 2014 showed that we can reduce the total amount of whey required to maximally stimulate MPS if a greater amount of leucine is added (ex. 6 g whey, 5 g leucine compared to 25 g whey). BUT since we need all 9 essential amino acids to build new proteins, getting adequate amounts of all the essential amino acids is still critical. Consuming leucine alone would
help to stimulate the MPS response, but we still need all the building blocks to make new protein.
Q: Since leucine is not usually listed on food labels, how can we determine how much leucine a food contains?
Dana Angelo White: Familiarize yourself with common plentiful sources that someone would eat in reasonable portions. For example, 4 ounces of low-fat cottage cheese contains 1.4 g, one large egg has 0.54 g, and 3 ounces of cooked salmon has 1.9 grams. I have been researching the leucine content of Greek yogurt, and it appears to have more leucine compared to traditional yogurt based on the concentrated amount of total protein per serving. The amino acid profile of most foods are available via
the USDA’s National Nutrient Database. https://www.nal.usda.gov/sites/default/files/page-files/leucine.pdf
Q: Are protein-fortified foods as effective as naturally protein-rich whole foods?
Dana Angelo White: Both fortified and whole foods can be utilized to help people reach their protein goals. As far as the protein itself, if the source of fortification is high quality (has all essential amino acids) and the dose is equivalent, a strong argument can be made that they would be equally effective from an amino acid standpoint. The other thing to consider is the comparison of the other nutrients found in the fortified versus the whole food. Paying attention to micronutrient, fiber, sugar and sodium content should also be considered.
