Whey protein

Fast-absorbing complete dairy protein with a high leucine content.

Supplements

Research records

Historical source snapshot. Not freshly verified, not a recommendation. Study findings, community accounts and app defaults are not interchangeable.

Publication suitability · 2026-10-15: Historical reference only; not a clinical verification. Clinical, regulatory, efficacy, safety and dose claims are not independently established by this review.

Whey protein

Fast-absorbing complete dairy protein with a high leucine content.

Evidence category: Systematic review. This describes the source category, not approval or certainty.

Regulatory statement in source: Not separately recorded; do not infer approval from the evidence category.

Whey protein is a milk protein taken as a supplement. A systematic review with meta-analysis of 25 trials in older adults examined body composition, strength and cardiometabolic markers, usually alongside resistance training. A meta-analysis in postmenopausal women found benefits for strength and lean mass mainly where resistance training was part of the programme. A third meta-analysis looked at recovery of muscle function after resistance exercise. Evidence comes from several meta-analyses of randomised trials, and results depend heavily on training.

Benefits reported in the imported source

Pooled randomised trials in older adults show a small gain in lower-body strength.
In postmenopausal women, strength and leg lean mass improved where resistance training was included.
Small to medium effects on recovery of muscle function after resistance exercise.

Risks and limits

No change in fat mass, lean mass, waist or blood lipids in older adults; fasting insulin rose.
Only half the recovery studies found any benefit; the rest found none against control.
Results depend heavily on resistance training happening alongside it.

Source bottom line: Whey protein adds small strength and recovery gains mostly when paired with resistance training, not alone.

Uncertainty: Reference information only. Not medical advice.

Study protocols — reports, not instructions

1,454 older adults aged 64-84 across 25 randomised controlled trials

Reported regimen: 15 to 35 g of whey protein a day, with or without leucine enrichment, against maltodextrin or non-protein controls; 15 trials paired it with resistance training
Duration: 8 weeks to 2 years, most commonly 12-16 weeks
Reported outcome: Lower-body strength rose slightly (SMD 0.16); no change in fat mass, lean mass, waist or blood lipids and glucose, while fasting insulin and HOMA-IR rose.
Source: Effects of Whey Protein Supplementation on Body Composition, Muscular Strength, and Cardiometabolic Health in Older Adults: A Systematic Review with Pairwise Meta-Analysis

Claim provenance

evidence.json#/catalog:supplement:whey-protein/protocols/0

152 subjects, 92% male and mostly young untrained men, across 13 randomised trials in 8 studies

Reported regimen: a median 25 g bolus of whey protein (range 20-120 g in total), given after exercise in 62% of trials, before in 23% and both in 15%, usually repeated through recovery
Duration: the recovery window after a bout of damaging eccentric resistance exercise
Reported outcome: Small to medium effects on recovery of muscle function (0.4-0.7), but only half the studies reported any benefit and the rest found none against control.
Source: The Effect of Whey Protein Supplementation on the Temporal Recovery of Muscle Function Following Resistance Training: A Systematic Review and Meta-Analysis

Claim provenance

evidence.json#/catalog:supplement:whey-protein/protocols/1

776 postmenopausal women aged 57-74 across the included trials

Reported regimen: 20 to 40 g of protein supplement daily; 11 studies combined it with resistance training and 4 gave it alone
Duration: 10 to 72 weeks, most commonly 12 weeks
Reported outcome: Biceps curl strength and lower-limb lean mass improved with resistance training; no effect on grip strength, knee strength, gait speed, fat mass or weight.
Source: Effect of Whey Protein Supplementation in Postmenopausal Women: A Systematic Review and Meta-Analysis

Claim provenance

evidence.json#/catalog:supplement:whey-protein/protocols/2

Community and practice descriptions

Accounts of a practice are not evidence of safety or effectiveness. Words such as “standard”, “safe” or “recommended” describe the source account, not verified consensus or this wiki’s advice. Commercial and self-published citations are retained for traceability, not vendor endorsement or independent clinical corroboration.

Unverified imported account — Should You Have a Protein Shake Before or After Your Workout? - Healthline

An imported authored paraphrase, not a quotation or a recommended protocol.

Review: unverified historical account. The imported wording is preserved for attribution; its full clinical, dosing, efficacy or consensus claims have not been independently established. Unvalidated source account; no validated human dosing population or animal-to-human equivalence is inferred.

Imported wording: A nutrition guide describes protein shakes as commonly used after workouts and lists whey as a powder used before or after training; powders typically contain 20-30 g of protein per scoop.

Should You Have a Protein Shake Before or After Your Workout? - Healthline

Historical research outcome: verified-description · 2026-10-06

Rechecked the previously published description against live source content. The live guide describes shakes between meals or around workouts and specifies the powder's usual protein content per scoop. The description does not assert a superior training time.

https://www.healthline.com/nutrition/protein-shake-before-or-after-workout: verified-description — The live guide describes shakes between meals or around workouts and specifies the powder's usual protein content per scoop. The description does not assert a superior training time.

Pharmacokinetic context

No half-life recorded in this source snapshot. No value has been inferred.

Source references

Snapshot provenance

Source ID: catalog:supplement:whey-protein. Commit: adc7684614f9439b41d91a3312b62e7982c7e20e. Review state: historical-not-reverified. Authored links are retained separately from the canonical evidence links in the public data. App templates/defaults and rejected drafts are archived, not deployed.

Related entries and components

None listed.