← Back to directory

Everyday Supplements 99%+ Pure L-Theanine 200 mg (90 capsules)

Lab verifiedLab: Harken ResearchReport: 1 Sep 2026Batch: ES-CL-LTHN-000003

About L-Theanine: what it is, forms and doses →

Compare all 2 L-Theanine →

Protein / amino acidsUK seller✓ Lab verified

A 9.4/10 How we score →

Lab report

Lab-test status
Lab verified1 Sep 2026Report
Lab
Harken Research, Pasadena, CA (US)
Harken Research certificate of analysis, sample 26HKN3422.21801 (L-Theanine capsules; heavy metals and L-theanine content)
Batch
ES-CL-LTHN-000003
Report date
1 Sep 2026
Heavy metals (mg/kg)
Pb <0.025 (well under the EU limit or below detection)Cd <0.022 (well under the EU limit or below detection)Hg <0.005 (well under the EU limit or below detection)As <0.010 (well under the EU limit or below detection)
Fillers
None
Heavy-metal colours: Well under the EU limit (below half) or below detection Near the EU limit (half the limit up to the limit) Over the EU limit Grey: no EU limit (arsenic), not tested, or the lab’s reporting limit is above the EU limitEU 2023/915 limits for food supplements: lead (Pb) 3.0, cadmium (Cd) 1.0, mercury (Hg) 0.10 mg/kg. Values in mg/kg. NT = not tested; c = calculated by us from µg per serving.
Ingredient
L-Theanine
Brand
Everyday Supplements
Testing rule for this category
Third-party testing preferred
Status detail
An independent lab report or certification is referenced for this product.
Reviewer notes
Harken Research (US) certificate issued 1 Sep 2026, batch ES-CL-LTHN-000003: L-theanine 101.65% (200.26 mg per capsule against 200 mg on the label, HPLC); lead, cadmium, mercury and arsenic all below the detection limit (ICP-MS). Separate Daane Labs microbiology report for the same batch (24 Aug 2026). UK seller.
Product page
Everyday Supplements (everydaysupplements.co.uk, UK)

⚠ 2 red flags

  • Tested by a US lab (Harken Research); the certificate does not state an accreditation (the seller says its labs are ISO 17025 accredited).
  • The report covers batch ES-CL-LTHN-000003 only: check the batch number on the base of your pack.

Purity & biohacker panel

Facts only, no scores. Lab: Harken Research, Pasadena, CA (US) · Harken Research certificate of analysis, sample 26HKN3422.21801 (L-Theanine capsules; heavy metals and L-theanine content) · batch ES-CL-LTHN-000003 · dated 2026-09-01 (report age 2 months).

Cleanliness checks

Free of fillers and additivesYes
Seller states no fillers or additives; ingredients: L-theanine and an HPMC capsule shell · seller page
Full ingredient list publishedYes
L-theanine; capsule shell: hydroxypropyl methylcellulose (HPMC) · seller page
Lead (Pb)Yes
<0.025 mg/kg (below the detection limit), EU supplement limit ≤ 3.0 · lab report
Cadmium (Cd)Yes
<0.022 mg/kg (below the detection limit), EU supplement limit ≤ 1.0 · lab report
Mercury (Hg)Yes
<0.005 mg/kg (below the detection limit), EU supplement limit ≤ 0.10 · lab report
Arsenic (As)Yes
<0.010 mg/kg (below the detection limit), total arsenic; no EU limit for supplements · lab report
MicrobiologyYes
Daane Labs (Naples, FL, US), 24 Aug 2026, same batch: total plate count and yeast & mould <100 cfu/g, coliforms <10 cfu/g; E. coli, Salmonella and S. aureus negative in 10 g · lab report
PesticidesUnknown
Not in the published report · no source
Label accuracy (measured vs claim)Yes
L-theanine 200.26 mg per capsule measured against 200 mg on the label (101.65%, HPLC) · lab report

Biohacker parameters

Form
Capsules (vegan HPMC) · seller page
Dose per serving
200 mg per capsule; label says 1–2 capsules a day · seller page
Servings per pack
45–90 days at 2–1 capsules a day (90 capsules) · seller page
Price / cost per daily dose
£32.99 / 90 capsules ≈ £0.37–£0.73 per day at 1–2 capsules (calculated, checked 22 Oct 2026). No EU seller on file. · seller page
Branded ingredient
Unknown · no source
Sourced / made in
UK company (London); made in a GMP-certified facility (seller; country not stated) · seller page
Capsule material
HPMC (vegan) · seller page
Allergens
Unknown · no source
Vegan
Yes · seller page
Third-party certifications
GMP-certified facility (seller); no product certification · seller page
Report age
2 months · lab report

Unknown = not published or not verifiable. Prices from the linked seller page, checked 22 Oct 2026.

Testing evidence

Other L-Theanine options