100g of Protein in One Meal - Is It a Waste?

Scientific concepts / nature phenomena presented

• Protein absorption kinetics after a meal

  • A cited study examined ingestion of 100 g of protein in one sitting after resistance training, finding delayed absorption over ~12 hours.

• Splanchnic sequestration (gut/organ uptake vs muscle delivery)

  • Not all amino acids from ingested protein reach skeletal muscle; a portion is absorbed by the digestive system and other organs before reaching muscle.

• Age-related “anabolic resistance” (reduced muscle-building response)

  • The discussion suggests that with aging, splanchnic sequestration increases, reducing amino acids reaching the blood/muscle—potentially requiring more protein for similar anabolic effects.

• Amino acid delivery vs muscle protein synthesis (MPS)

  • The study traced where amino acids went (including via radioisotope tracing) and emphasized that muscle uptake doesn’t automatically mean equivalent muscle protein synthesis; MPS is the key functional endpoint.

• Dose-response / diminishing returns for protein

  • Compared reported muscle-relevant delivery/utilization estimates:
    • 25 g dose: ~18% of amino acids from the dose reached skeletal muscle (or the study’s skeletal muscle endpoint)
    • 100 g dose: ~13% reached skeletal muscle
  • Interpretation: increasing protein above moderate doses yields diminishing anabolic returns (rate of benefit decreases).

• Methodological limitation: muscle sampling scope

  • The study used biopsies from only one muscle (vastus lateralis) and then estimated whole-body / overall muscle outcomes, which may limit precision.

• Protein type and digestion rate (milk protein vs whey/casein)

  • The study used milk protein.
  • Discussants argue real-world post-workout comparisons often involve whey (faster) or casein (slower), and proposed adding study arms for whey and casein (including mixed formulations like whey + casein).

• Insulin and glucagon responses to protein

  • Whey protein is described as insulinogenic and also associated with glucagon increase.
  • Carbohydrates are described as primarily driving insulin with less glucagon change, whereas protein is framed as “net neutral” for glucose stability due to glucagon counter-regulation.

• Protein as fat-loss supportive despite insulin concerns

  • Addressed a common belief that protein’s insulin response might impede fat loss (e.g., effects on lipid metabolism enzymes).
  • The response emphasizes that outcome studies matter more than isolated mechanisms.
  • It’s claimed that extra protein improves fat loss mainly when initial protein intake is suboptimal (example: women performing non–resistance training with low baseline protein who increase to more adequate amounts).

Study / methodology outlined (from the discussion)

• Study design (acute protein after resistance training)

  • Participants receive either:
    • 25 g protein
    • or 100 g protein
  • Protein source: milk protein.

• Amino acid tracing and endpoints

  • Amino acid tracing quantifies:
    • how much amino acid is sequestered by the splanchnic (gut/organ) route
    • how much reaches peripheral circulation
    • how much ultimately reaches skeletal muscle (using biopsy data and/or estimates)
  • Measurement emphasis includes:
    • muscle uptake
    • discussion of muscle protein synthesis (MPS) as the functional anabolic endpoint

• Reported comparison

  • 18% vs 13% “made it” to the skeletal muscle endpoint for 25 g vs 100 g doses.

• Sampling limitation

  • Biopsies taken from vastus lateralis only, with extrapolation across the body.

Researchers / sources featured (named in the subtitles)

• Mike Israetel
• Peter Attia
• Rhonda Patrick
• PubMed (cited as a place where title/formatting is observed)