L-Leucine

Compare every L-Leucine product across UK retailers on Suppio, ranked by true value - price per active dose, not pack size. Prices refreshed daily.

Essential branched-chain amino acid that is the primary trigger for muscle protein synthesis

We rank L-Leucine by price per gram of active ingredient - not by pack size - so a bigger tub with a worse price per dose can't outrank a smaller one that's actually cheaper.

What it is

L-Leucine is an essential branched-chain amino acid. This means it is a building block for protein that the body cannot make on its own, so it must be obtained through food or supplements.

Why it's used

It is primarily used to help build muscle. It acts as the main trigger for muscle protein synthesis, which is the biological process where the body uses amino acids to repair and grow muscle tissue.

How it's made

To create the supplement, the amino acid is typically extracted from protein sources through a process called fermentation. Bacteria are used to produce the leucine, which is then filtered, purified, and dried into a powder for use in capsules or tubs.

What it typically costs

This ingredient is generally mid-range in price. This is because the fermentation process required to isolate the specific amino acid is more complex than simple protein extraction, but there is enough global supply and competition to keep costs from becoming premium.

Dosage by purpose

PurposeTypical studied doseEvidence
maximize protein synthesis and minimize leucine oxidation in healthy young adults55 mg per kilogram of bodyweight per dayestablished
enhance muscle strength in older adultsprotein intake from 1.0 to 1.5 grams per kilogram per day with addition of leucine-enriched protein supplementationemerging
  1. https://pmc.ncbi.nlm.nih.gov/articles/PMC5118760 (PubMed)
  2. https://pmc.ncbi.nlm.nih.gov/articles/PMC9284268 (PubMed)
  3. https://pmc.ncbi.nlm.nih.gov/articles/PMC12764641 (PubMed)

How Suppio ranks

Suppio matches identical products across UK retailers by barcode, then ranks by price per active dose rather than sticker price. Value rankings only ever include listings Suppio has independently verified against the live retailer page - unverified data is shown on each product’s own page but excluded from ranking.

Prices across our retailer network are refreshed at least daily.

FAQ

What is L-Leucine?

Essential branched-chain amino acid that is the primary trigger for muscle protein synthesis

How does Suppio calculate the best-value L-Leucine?

We rank L-Leucine by price per gram of active ingredient - not by pack size - so a bigger tub with a worse price per dose can't outrank a smaller one that's actually cheaper.

Are these prices verified?

Suppio matches identical products across UK retailers by barcode, then ranks by price per active dose rather than sticker price. Value rankings only ever include listings Suppio has independently verified against the live retailer page - unverified data is shown on each product’s own page but excluded from ranking.

How often are L-Leucine prices updated?

Prices across our retailer network are refreshed at least daily.

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