The Claim

In healthy men, aging is associated with a reduction in the systemic availability of dietary protein–derived phenylalanine by 6 percentage points over 5 hours following casein ingestion, decreasing from 51% ± 14% in young men to 45% ± 10% in older men, which suggests that older age attenuates postprandial amino acid absorption kinetics and reduces the efficiency of dietary protein utilization.

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

As men get older, their bodies don't absorb protein from food as well after eating — specifically, older guys get less use out of the amino acids from a protein meal compared to younger guys.

See the scientific wording

In healthy men, aging reduces the systemic availability of dietary protein–derived phenylalanine by 6 percentage points (from 51% ± 14% in young men to 45% ± 10% in older men) over 5 hours after casein ingestion, indicating that older age attenuates postprandial amino acid absorption kinetics and reduces the efficiency of dietary protein utilization in older individuals.

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 shows that older men absorb less protein from their food than younger men after eating, just like the claim says.

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

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