The Claim

In healthy adult men, approximately 50% (±14%) of dietary protein–derived phenylalanine from intact whey, casein, or milk protein appears in the systemic circulation within 5 hours after ingestion, indicating that about half of the ingested protein is absorbed and becomes available to peripheral tissues such as muscle during this time, while the remainder is either retained in splanchnic tissues or not yet fully digested.

Source: Protein Type, Protein Dose, and Age Modulate Dietary Protein Digestion and Phenylalanine Absorption Kinetics and Plasma Phenylalanine Availability in Humans

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
88score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Quantitative
1 study reviewed
In plain English

When healthy guys drink milk protein, about half of the protein gets into their bloodstream within 5 hours — that's what muscles can use. The rest is either still being digested or gets used by organs like the liver before it ever reaches the rest of the body.

See the scientific wording

In healthy adult men, 50% ± 14% of dietary protein–derived phenylalanine appears in the systemic circulation within 5 hours after ingestion of intact whey, casein, or milk protein, indicating that approximately half of ingested dietary protein is absorbed and made available to peripheral tissues such as muscle during this period, while the remainder is either retained in splanchnic tissues or not yet fully digested.

What the research says

1 study
  1. Study: Protein Type, Protein Dose, and Age Modulate Dietary Protein Digestion and Phenylalanine Absorption Kinetics and Plasma Phenylalanine Availability in Humans

    The study found that about half of the protein you eat shows up in your blood within 5 hours, which matches what the claim says.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.