L-Isoleucine

Compare every L-Isoleucine 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 supporting energy production and muscle recovery

We rank L-Isoleucine 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-Isoleucine is an essential branched-chain amino acid. Amino acids are the building blocks that the body uses to make proteins, and "essential" means your body cannot produce it on its own, so you must get it from your diet or supplements.

Why it's used

It is primarily used to support the following:

How it's made

To create the supplement, the amino acid is typically isolated from natural protein sources through a process called fermentation. Microorganisms are used to produce the specific amino acid, which is then filtered, purified, and dried into a stable powder for use in capsules or drink mixes.

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 extraction, but there is enough global supply and competition to prevent it from becoming a luxury-priced supplement.

Dosage by purpose

PurposeTypical studied doseEvidence
General nutritional requirements19 mg per kilogram of bodyweight dailyestablished
Improving liver frailty index and muscle mass in compensated cirrhotic patients3.52 grams per dayemerging
Safety in patients with amyotrophic lateral sclerosis8 grams per daylimited
  1. https://examine.com/supplements/isoleucine (Examine)
  2. https://pmc.ncbi.nlm.nih.gov/articles/PMC12845092 (PubMed)
  3. https://pmc.ncbi.nlm.nih.gov/articles/PMC7468706 (PubMed)
  4. https://pmc.ncbi.nlm.nih.gov/articles/PMC10334138 (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-Isoleucine?

Essential branched-chain amino acid supporting energy production and muscle recovery

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

We rank L-Isoleucine 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-Isoleucine prices updated?

Prices across our retailer network are refreshed at least daily.

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