Whey protein

Tier 1 — strong evidence · Muscle synthesis · Sarcopenia

A fast-digesting, leucine-rich complete protein derived from dairy with the highest bioavailability of any common protein source. A 2024 meta-analysis specifically in sarcopenic older adults (Li et al., 10 RCTs, 1,154 participants, PMID 38350303) confirmed whey protein significantly improves appendicular skeletal muscle mass, gait speed, and — when combined with resistance training — handgrip strength. A 2023 systematic review in sarcopenic adults (Cuyul-Vasquez, 7 RCTs, 591 participants, PMID 37571361) also found significant handgrip gains (+2.31 kg). Effect sizes are small-to-moderate in…

Dose: 20-40 g per serving; aim for 1.6-2.2 g/kg/day total protein from all sources for muscle gain, or 1.2-1.5 g/kg/day for sarcopenia prevention. Isolate for lactose intolerance.