The Claim

In healthy young adults, ingestion of free amino acids results in greater incorporation of dietary phenylalanine into mixed muscle protein compared to intact milk protein, as evidenced by significantly higher muscle-bound l-[1-13C]-phenylalanine enrichment at 6 hours (0.033 ± 0.011 vs. 0.024 ± 0.008 MPE).

Source: Ingestion of Free Amino Acids Compared with an Equivalent Amount of Intact Protein Results in More Rapid Amino Acid Absorption and Greater Postprandial Plasma Amino Acid Availability Without Affecting Muscle Protein Synthesis Rates in Young Adults in a Double-Blind Randomized Trial

What the research says

Challenges is higher

Challenge is ahead, but a single strong supporting study can change this.

Supports
0score
Challenges
80score

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

If you're a healthy young adult, your muscles might use amino acids from supplements better than from real milk—scientists tracked this by seeing how much labeled phenylalanine ended up in muscle over 6 hours.

See the scientific wording

In healthy young adults, ingestion of free amino acids leads to greater incorporation of dietary phenylalanine into mixed muscle protein compared to intact milk protein, with significantly higher muscle-bound l-[1-13C]-phenylalanine enrichment at 6 hours (0.033 ± 0.011 vs. 0.024 ± 0.008 MPE).

What the research says

1 study

  1. Study: Ingestion of Free Amino Acids Compared with an Equivalent Amount of Intact Protein Results in More Rapid Amino Acid Absorption and Greater Postprandial Plasma Amino Acid Availability Without Affecting Muscle Protein Synthesis Rates in Young Adults in a Double-Blind Randomized Trial

    The study found that even though free amino acids get into the blood faster, they don’t lead to more muscle building than whole milk protein in young adults.

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

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