Research

Hormonal

Whey protein isolate is superior to other protein sources for stimulating muscle protein synthesis in older adults due to its high leucine content.

For older adults, whey protein isolate is an excellent choice for stimulating muscle growth because it is rich in leucine, the key trigger for muscle synthesis. If you cannot consume dairy, combine plant proteins to ensure adequate leucine intake.

GoodSupportsHIGH confidence
Thus, as Table 2 highlights milk-based proteins would be, gram-for-gram, better sources of protein to provide to support the delivery of leucine to support MPS. ... Whey protein isolate ... leucine AARR 2.57
Stuart M. Phillips · Frontiers in Nutrition · 2017

Why this rating

Supported by mechanistic studies on leucine sensitivity and AARR data.

Source

Current Concepts and Unresolved Questions in Dietary Protein Requirements and Supplements in Adults

Stuart M. Phillips · Frontiers in Nutrition · 2017

DOI 10.3389/fnut.2017.00013

narrative_reviewCited 138×
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DOI resolved against Crossref · corpus check 2026-06-10

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