Best Amino Acids UK — 2026 Guide
L-theanine, glycine, BCAAs, glutamine, citrulline, taurine, and EAA blends. Compare forms, dosages, and value across UK supplement shops.
We analysed 12 amino acids by aggregating real user reviews from Reddit, Amazon UK, YouTube, and specialist health forums. Our AI evaluates each product across six categories — effectiveness, ingredient quality, value for money, side effects, certifications, and overall score — so you can make an informed decision without spending hours reading individual reviews.
How We Compare Amino Acids
We collect public reviews from Reddit, Amazon, YouTube, Trustpilot, and specialist forums to build a complete picture.
Our AI reads every review, checks ingredient labels, fillers, and certifications, then generates an unbiased summary.
Products are scored 1-10 across six evidence-based categories, making it easy to compare at a glance.
12 products
Bulk BCAA Powder 2:1:1
Bulk
Bulk's unflavoured BCAA powder is the pure value play — 100 servings of clean BCAAs at the lowest price per gram in the ...
Bulk Citrulline Malate Powder 2:1
Bulk
Bulk's Citrulline Malate is one of the most evidence-backed pre-workout ingredients available, and this is the cheapest ...
Bulk Glycine Powder
Bulk
Bulk's Glycine Powder offers the same pure amino acid as NOW Foods in a larger 500g quantity at a lower UK price. The se...
Bulk L-Theanine Capsules 250mg
Bulk
Bulk's L-Theanine is the budget king of the UK theanine market, offering the highest dose and lowest price per serving. ...
Myprotein BCAA 4:1:1 Powder
Myprotein
Myprotein's BCAA 4:1:1 offers a leucine-heavy ratio at a competitive UK price. The 5g per serving provides more total BC...
NOW Foods Glycine Pure Powder
NOW Foods
NOW Foods Glycine Powder is one of the highest-value sleep supplements available if you follow the clinical dose of 3g b...
NOW Foods L-Glutamine 1000mg
NOW Foods
NOW Foods L-Glutamine is a reliable capsule option for those wanting to supplement this conditionally essential amino ac...
NOW Foods L-Theanine 200mg
NOW Foods
NOW Foods L-Theanine is arguably the best value L-theanine product for UK consumers. The use of patented Suntheanine ens...
NOW Foods Taurine 1000mg
NOW Foods
NOW Foods Taurine is a cheap and cheerful way to supplement one of the amino acids generating the most research exciteme...
Optimum Nutrition BCAA 1000 Caps
Optimum Nutrition
Optimum Nutrition BCAA 1000 is the market leader in capsule BCAAs, offering a convenient and well-dosed product from a t...
Solgar L-Theanine 150mg Free Form
Solgar
Solgar's L-Theanine offers the brand's characteristic quality assurance but at a significant price premium over equally ...
Thorne Amino Complex
Thorne
Thorne Amino Complex represents the pinnacle of amino acid supplementation — all nine EAAs in researched ratios with NSF...
Amino Acids Buying Guide — What to Look For
Choosing the right amino acids can be overwhelming with hundreds of options on the UK market. Here are the key factors our AI analyses when scoring each product:
Bioavailability & Forms
Not all supplement forms are created equal. For example, magnesium glycinate absorbs much better than magnesium oxide. We check which forms are used and whether they're backed by research for optimal absorption.
Clean Label & Fillers
Many supplements contain unnecessary fillers, artificial colours, added sugars, and bulking agents. Our AI flags products with excessive additives and rewards clean formulations.
Third-Party Testing
Independent lab testing verifies that what's on the label is actually in the bottle. Products with third-party certifications (NSF, USP, Informed Sport) score higher in our rankings.
Value per Serving
The cheapest bottle isn't always the best value. We calculate the cost per serving and weigh it against ingredient quality, dosage, and overall effectiveness reported by users.
How Our Scoring Works
Each product is scored 1-10 across six categories. An overall score of 8+ indicates a product we'd recommend to most people. Scores of 6-7 are solid choices with some trade-offs, while anything below 6 has significant drawbacks reported by users. Our scores are recalculated regularly as new reviews come in.
Frequently Asked Questions
Where do you get your reviews?
We aggregate publicly available reviews from Reddit, Amazon UK, YouTube, Trustpilot, and specialist health forums. We never use manufacturer-provided testimonials.
How often are scores updated?
Our AI re-analyses reviews and updates scores regularly. Product pages show the date of the latest analysis.
Do you receive products for free?
No. AIScored does not accept free products or sponsored placements. Our revenue comes from affiliate links, which do not influence our scores.
Disclaimer: AIScored provides AI-generated summaries based on publicly available reviews and product information. This is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Prices are updated regularly but may differ at the time of purchase. Affiliate links may earn us a commission at no extra cost to you.