Sarcopenia and the Protein Threshold: Reconciling Requirement Estimates With What Older Patients Actually Eat
DOI:
https://doi.org/10.5281/zenodo.22278410Keywords:
Sarcopenia, Protein requirement, Older adults, Indicator amino acid oxidation, Dietary intakeAbstract
How much protein an older adult requires depends on how the question is asked. Nitrogen balance studies underpin the current
allowance of 0.8 grams per kilogram daily, identical for all adults; indicator amino acid oxidation gives an average requirement
of 0.9 and an allowance of 1.2 in the same age group, roughly 40 per cent higher. In nine older adults with sarcopenia the
oxidation method returned an average requirement of 1.21 grams per kilogram daily, with a recommended intake of 1.54, though
the confidence interval on that second figure runs from 1.13 to 1.95. Expert recommendation sits at 1.0 to 1.2 for healthy older
people and 1.2 to 1.5 in illness. Measured intake has not moved with the recommendations: against the current average
requirement of 0.66, between 20 and 24 per cent of older women and 5 to 12 per cent of older men fall below.
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