The Claim

Measurements of nitrogen loss using 40K and creatinine indicate that integumental nitrogen loss is approximately 15 mg/kg/day, which is higher than the 5 mg/kg/day assumed in the 1973 FAO/WHO nitrogen requirement allowances, suggesting that total nitrogen requirements may be underestimated.

Source: Human protein requirements: a long-term metabolic nitrogen balance study in young men to evaulate the 1973 FAO/WHO safe level of egg protein intake.

What the research says

Supports is higher

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

Supports
25score
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

Scientists found that we lose more nitrogen through our skin than previously thought—about three times more. This means the old guidelines for how much protein we need might be too low.

See the scientific wording

Measurements of nitrogen loss via 40K and creatinine suggest a higher integumental nitrogen loss (≈15 mg/kg/day) than the 5 mg/kg/day assumed in the 1973 FAO/WHO allowances, indicating potential underestimation of total nitrogen requirements.

What the research says

1 study

  1. Study: Human protein requirements: a long-term metabolic nitrogen balance study in young men to evaulate the 1973 FAO/WHO safe level of egg protein intake.

    The study found that people lose more nitrogen through their skin than scientists previously thought, meaning we need more protein in our diet than old guidelines said. This proves the old numbers were too low.

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

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