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    Whey Protein

    Whey is a fast-digesting dairy protein with the highest leucine content of any common protein source, which makes it the most efficient way to trigger muscle protein synthesis after training.

    Effective dose

    20–40 g per serving, one to two servings a day as needed to reach your daily protein target.

    Timing

    Any time. Post-workout is convenient, but the daily total and spreading protein across meals matter far more.

    What it is

    Whey is the liquid fraction left when milk is separated during cheesemaking. Concentrate is roughly 70–80% protein with some lactose and fat. Isolate is filtered further to 90%+ protein with very little lactose. Hydrolysate is pre-broken-down for faster absorption.

    How it works

    Muscle repair is driven by amino acids, and leucine is the trigger. Whey delivers around 2.5–3 g of leucine per 25 g serving, which comfortably crosses the threshold that switches muscle protein synthesis on.

    What the research shows

    • Whey raises muscle protein synthesis faster and higher than casein or most plant proteins per gram.
    • Total daily protein intake still matters more than any single shake; whey is a convenient way to hit the target.
    • 1.6–2.2 g of protein per kg of bodyweight per day supports muscle gain in people who resistance train.

    Best for

    Building muscleRecovery after trainingHitting protein targetsHigher-protein fat loss

    Forms to look for

    • Concentrate (best value)
    • Isolate (low lactose, leaner)
    • Hydrolysate (fastest, priciest)

    What to watch out for

    Proprietary blends can hide amino spiking. Look for a clear protein-per-serving number and third-party testing such as NSF Certified for Sport or Informed Sport.

    Sourcing partners

    Coming soon

    We are onboarding a short list of vetted suppliers for whey protein, each with published certificates of analysis and third-party identity testing. Direct purchasing will open here once those partners are live.

    Become a sourcing partnerBuying in bulk? Visit the marketplace

    FAQs

    Is whey isolate worth the extra money?

    It is if lactose bothers you or you want the leanest possible macros. Otherwise concentrate delivers nearly the same result for less.

    Can I use whey if I do not train?

    Yes. It is simply a convenient, high-quality protein source for anyone struggling to hit daily protein.

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    Protein supplementsBest protein powderWhey vs plant protein

    Educational information only, not medical advice. Talk to your physician or a registered dietitian before starting a supplement, especially if you are pregnant, nursing, managing a health condition, or taking medication.