Best Nattokinase Supplements UK 2026
Last updated: 1 June 2026 · 7 products reviewed
Nattokinase is a fibrinolytic enzyme from fermented soybeans, taken for cardiovascular and circulatory support and measured in Fibrinolytic Units (FU). It's also one of the easiest supplements to get wrong: the enzyme is delicate and degrades in manufacturing and storage, so independent testing repeatedly finds products containing a fraction of their claimed FU — some as low as 18%. We ranked UK nattokinase supplements by independently-verified potency, transparency and value, so you only pay for enzyme that's actually there.
Our Top 3 Picks at a Glance
Comparison Table
| # | Product | Form | Potency | Price | Cost/1000 FU | Score | Award |
|---|---|---|---|---|---|---|---|
| 1 | NF Nattokinase Arterial Support 5,000 FU NF Supplements | Capsule | 5,000 FU (tested 5,210) | £29.99 | £0.20 | 9.4 | Best Overall |
| 2 | Horbaach Nattokinase 4,000 FU Horbaach | Capsule | 4,000 FU (tested 3,720) | £16.99 | £0.07 | 7.6 | Best Value Verified |
| 3 | Doctor's Best Nattokinase 2,000 FU Doctor's Best | Capsule | 2,000 FU (low dose) | £24.99 | £0.14 | 6.2 | Best Established Brand |
| 4 | Double Wood Nattokinase 4,000 FU Double Wood | Capsule | 4,000 FU (tested 2,800) | £15.99 | £0.04 | 6.0 | — |
| 5 | NOW Foods Nattokinase 100mg NOW Foods | Capsule | 100mg (≈2,000 FU) | £18.53 | £0.15 | 5.8 | Best Budget |
| 6 | Nutricost Nattokinase 2,000 FU Nutricost | Capsule | 2,000 FU | £14.99 | £0.06 | 5.6 | — |
| 7 | Vegavero Nattokinase 2,000 FU Vegavero | Capsule | 2,000 FU | £19.99 | £0.11 | 5.3 | — |
NF Nattokinase Arterial Support 5,000 FU
Capsule
Horbaach Nattokinase 4,000 FU
Capsule
Doctor's Best Nattokinase 2,000 FU
Capsule
Double Wood Nattokinase 4,000 FU
Capsule
NOW Foods Nattokinase 100mg
Capsule
Nutricost Nattokinase 2,000 FU
Capsule
Vegavero Nattokinase 2,000 FU
Capsule
Detailed Reviews & Rankings
NF Nattokinase is our #1 pick — the only brand in independent testing to exceed its label claim (5,210 FU vs 5,000 FU stated), with every batch lab-tested by SORA Labs and Certificates of Analysis published publicly. Verified K2-free and made in Oxford.
Pros
- The ONLY brand to exceed its label claim — lab tested at 5,210 FU vs 5,000 FU claim (104% potency)
- Every production batch independently tested by SORA Labs with COAs published publicly
- Made in-house at their own GMP facility in Kidlington, Oxford — no white-labelling
Cons
- More expensive than budget alternatives
- Direct-only and Amazon — not on the high street
- Smaller brand with less mainstream recognition
Horbaach is our verified value pick — SORA Labs confirmed 3,720 FU against its 4,000 FU claim (93%), one of only two brands to pass independent testing. Cheaper than NF, with good UK availability.
Pros
- Second-best tested — SORA Labs confirmed 3,720 FU vs 4,000 FU claim (93%, within acceptable range)
- One of only two brands to pass SORA testing among 8 tested
- UK manufacturing claims (note: no longer available to buy in the UK — import only)
Cons
- No longer available in the UK — must be imported, adding cost and delivery time
- Came in slightly below label claim (93%)
- Higher dose per capsule may require adjusting serving size
Doctor's Best is a trusted, clinically-dosed pick — it passed ConsumerLab's independent 2025/2026 testing and uses the 2,000 FU dose seen in clinical studies, from a long-established brand.
Pros
- Independently verified — passed ConsumerLab's 2025/2026 testing (one of only 5 of 8 to pass)
- Wide availability and a mainstream, long-established brand
- Mid-range pricing
Cons
- Exact potency percentage not published (ConsumerLab doesn't release specific numbers)
- May need 2–3 capsules daily for a higher therapeutic dose
- Not SORA Labs tested
Double Wood is a budget option that scraped a pass in SORA testing — 2,800 FU against a 4,000 FU claim (70%). Genuine enzyme, but 30% under-dosed versus its label.
Pros
- SORA tested — confirmed 2,800 FU vs 4,000 FU claim (70%, just within acceptable threshold)
- Easy to order via Amazon UK
- Budget-friendly versus the top three
Cons
- Low real dose — only 2,800 FU verified despite the 4,000 FU label
- 30% under its label claim (2,800 FU vs 4,000 FU)
- Does not 3rd party test every batch
NOW Foods is the best budget pick — it passed ConsumerLab's independent testing, uses the research-standard 100mg formulation, and comes from a trusted decades-old brand at a low price.
Pros
- Passed ConsumerLab's 2025/2026 independent testing (one of 5 passing brands)
- Significantly cheaper than the top four
- Widely stocked on Amazon UK
Cons
- No SORA Labs specific potency data (only ConsumerLab pass/fail)
- May require multiple capsules daily for a higher dose
- Does not 3rd party test every batch
Nutricost is a strong value pick — it passed ConsumerLab testing, delivers the 2,000 FU clinical dose, and packs 120 servings per bottle for an excellent cost-per-serving.
Pros
- Passed ConsumerLab's 2025/2026 testing criteria
- 120 servings per bottle — a 4-month supply with excellent cost-per-serving
- One of the cheapest verified options
Cons
- Low 2,000 FU dose per capsule
- No SORA Labs specific potency percentage published
- Larger capsules
Vegavero offers a clean, additive-free 2,000 FU nattokinase, but it lacks the independent potency testing that the higher-ranked brands carry — so its real-world potency is unverified.
Pros
- Clean formula — no additives, fillers or unnecessary ingredients
- Easy to source via Amazon UK
- Vegan-friendly
Cons
- Low 2,000 FU dose per capsule
- Limited third-party testing data — not included in major ConsumerLab or SORA testing
- Least potency-verification transparency in our ranking
Brands to Avoid
These products are widely available but failed independent potency testing — each delivered only a fraction of the enzyme activity stated on the label. We recommend avoiding them.
Vinco
Independently tested at just 17.8% of its claimed potency — over 80% of the labelled enzyme activity was missing.
Hybrid Health
Independently tested at 27.6% of its claimed potency — delivering barely a quarter of the FU stated on the label.
Raibu
Independently tested at 26.4% of its claimed potency — far below the acceptable threshold for an active dose.
How to Choose a Nattokinase Supplement
Why Potency Testing Matters More Than Any Other Factor
Nattokinase is a fragile enzyme measured in Fibrinolytic Units (FU). Unlike a mineral, it can lose activity during manufacturing, shipping and shelf storage — so the FU on the label is often far higher than what's actually in the capsule. Independent testing has found brands delivering as little as 18–28% of their claimed potency. The single most important thing when buying nattokinase is independent, ideally per-batch, potency verification.
FU (Fibrinolytic Units) and Dosing
Nattokinase is dosed in FU, not milligrams of capsule weight. Clinical studies typically use 5,000–10,000 FU daily. Many products only provide 2,000–4,000 FU, which is a low dose by comparison — you would need several capsules to reach a research-level dose. And a higher label number is only meaningful if independent testing confirms the enzyme is genuinely present and active at that level.
The Vitamin K2 Consideration (Blood Thinners)
Natto naturally contains vitamin K2, which promotes blood clotting and can directly counteract anticoagulant medication such as warfarin. If you take blood thinners, a nattokinase product independently verified to be K2-free is important. Note that nattokinase itself has blood-thinning properties, so anyone on anticoagulants should consult their GP before taking it at all.
Testing Bodies: SORA Labs vs ConsumerLab
SORA Labs publishes specific potency percentages (e.g. 134% or 70% of claim), giving you an exact figure. ConsumerLab publishes a pass/fail verification without the precise number. Both are credible independent testers — a brand that passes either is far ahead of an untested product. The gold standard is per-batch testing with publicly published Certificates of Analysis.
Nattokinase FAQ
What is the best nattokinase supplement in the UK?
NF Nattokinase Arterial Support is our top pick — the only brand in independent testing to exceed its label claim (6,720 FU vs 5,000 FU stated), with per-batch Certificates of Analysis published publicly and verified vitamin K2-free status.
Why do so many nattokinase supplements fail testing?
Nattokinase is a delicate enzyme that loses activity during manufacturing, shipping and storage. Independent testing repeatedly finds products containing far less active enzyme than claimed — some as low as 18–28% of their stated FU. This is why independent potency verification is essential.
How much nattokinase should I take?
Clinical studies typically use 5,000–10,000 FU per day. Products providing only 2,000–4,000 FU are low-dose by comparison, so you would need several capsules to reach a research-level dose. What matters most is that the stated FU is independently verified — a high label number means nothing if the enzyme isn't actually present and active.
Is nattokinase safe with blood thinners?
Nattokinase has blood-thinning properties of its own, and many products contain vitamin K2 which can counteract anticoagulants like warfarin. If you take blood thinners, choose a verified K2-free product and always consult your GP before taking nattokinase.
What does FU mean for nattokinase?
FU stands for Fibrinolytic Units — the standard measure of nattokinase's enzymatic activity. It reflects how much active, functional enzyme is present, which is why it's a more meaningful figure than the milligram weight of the capsule contents.