Whey / Casein Protein

Evidence: ★★★★★ · Status: OTC Supplement

In plain English

Concentrated food. Leucine is the "build muscle now" trigger, and whey delivers a big hit of it. Total daily protein matters more than timing.

How it works

Complete proteins rich in leucine, which activates mTORC1 to trigger muscle protein synthesis. Whey is fast-absorbing (acute MPS spike); casein is slow (overnight anti-catabolism).

Molecular target & official sources

MTOR / mTORC1 (NCBI Gene) · Leucine (PubChem CID 6106)

Protocol

Fill the gap to 1.6–2.2 g protein/kg bodyweight/day.

Bottom line

Convenience, not magic. Hit your daily protein however you like.

Helps with: Build Muscle & Strength · Recover Faster

Stacks with

Creatine (add it to the same post-workout shake) and carbs.

Shares a pathway — often paired with: Rapamycin (Sirolimus), Insulin (anabolic misuse), Ketamine / Esketamine (Spravato), HMB (β-Hydroxy β-Methylbutyrate).

Availability & where to buy

Available over the counter. Widely available OTC — e.g. iHerb (ships worldwide); in Singapore also Guardian, Watsons, GNC, Shopee / Lazada. Look for a third-party-tested / GMP mark and check the dose per serving. ~S$50–80 per tub (~1 month). Whey isolate if lactose-sensitive.

How it works: the mTOR pathway →

Used in these protocols

• Muscle Loss (Sarcopenia)
• Build Muscle (Plateau)

Compare Whey / Casein Protein

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