Research

Macro partitioning

Whey protein supplementation alone has no significant effect on lean mass or muscle strength in healthy older adults, but significantly improves lean mass and physical function (specifically gait speed) in sarcopenic or frail older adults.

If you are a healthy older adult, whey protein alone is unlikely to build muscle or strength. However, if you have sarcopenia or frailty, whey protein can significantly improve your muscle mass and walking speed. Focus on your health status rather than just the supplement.

ModerateQualifiesLOW confidence
The analysis showed that whey protein supplementation had no effect on LM and muscle strength; nevertheless, a significant improvement was found in physical function... On the contrary, whey protein supplementation significantly improved LM... appendicular lean mass and physical function... in sarcopenic/frail older adults.
Nasrin Nasimi et al. · Advances in Nutrition · 2023

Why this rating

Based on a systematic review and meta-analysis of RCTs, but GRADE ratings were low to very low due to heterogeneity and risk of bias.

Source

Whey Protein Supplementation with or without Vitamin D on Sarcopenia-Related Measures: A Systematic Review and Meta-Analysis

Nasrin Nasimi et al. · Advances in Nutrition · 2023

DOI 10.1016/j.advnut.2023.05.011

Meta-analysis · 30 studiesCited 70×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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