Macro partitioning
Consuming the Recommended Dietary Allowance (RDA) of 0.8 g protein/kg/day for 14 weeks leads to a significant loss of mid-thigh skeletal muscle area in older adults (aged 55-77), indicating the RDA is inadequate for maintaining muscle mass in this population.
If you are over 55, the standard government recommendation of 0.8 grams of protein per kilogram of body weight is likely not enough to keep your leg muscles from shrinking. To maintain muscle mass, you should aim for a higher protein intake, potentially around 1.0 to 1.2 g/kg/day, while ensuring you eat enough total calories to maintain your weight.
Mid-thigh muscle area was decreased by 1.7 ± 0.6 cm2 (p < .019) at Week 14 compared with Week 2... These results suggest that the RDA for protein may not be adequate to completely meet the metabolic and physiological needs of virtually all older people.
Why this rating
Randomized controlled trial with precise dietary control and sensitive outcome measures (CT scans), though limited by small sample size (n=10) and short duration (14 weeks).
Source
The Recommended Dietary Allowance for Protein May Not Be Adequate for Older People to Maintain Skeletal Muscle
W. W. Campbell et al. · The Journals of Gerontology Series A · 2001
DOI 10.1093/gerona/56.6.m373
Related findings · Macro partitioning
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