Best Vitamin K2 Supplement in the UK (2026): MK-7 Picks, Ranked
Prices and cost per day here are from our US catalogue in USD. UK prices differ, use them to compare products with each other, not to budget in pounds. Buy buttons open the product on Amazon.co.uk; where a brand is not sold in the UK, the button opens an Amazon.co.uk search instead of a dead page.
Best overall:NOW Foods MK-7 100 mcg at $0.22/day — branded MenaQ7 (all-trans, soy-free), the trial-grade ingredient at the standard 100 mcg dose.
Best value:Nutricost MK-7 100 mcg at $0.07/day — same dose, lowest cost.
Best D3 + K2 combo:Sports Research D3 + K2 — 5,000 IU D3 with 100 mcg MK-7 in one softgel (see taking vitamin D with K2).
One note on verification: unlike melatonin, K2 products rarely carry a USP or NSF label-accuracy mark — so we weight the quality signals that do exist for K2: all-trans content and a branded, tested ingredient like MenaQ7.
Informational summary of published research — not medical advice. If you take warfarin or another vitamin K antagonist, do not start K2 without your physician. As an Amazon Associate we earn from qualifying purchases; picks are ranked by form quality and cost per day, never commissions.
Our Top Picks at a Glance
| Award | Product | Form | K2 Dose | Why this one | Cost/Day | Buy |
|---|---|---|---|---|---|---|
| Best Overall | NOW Foods MK-7 Vitamin K2 100 mcg | MK-7 (all-trans) | 100 mcg | Branded MenaQ7 — the all-trans, soy-free ingredient used in the clinical trials, at the standard dose. | $0.22 | Check price → |
| Best Value | Nutricost Vitamin K2 MK-7 100 mcg | MK-7 | 100 mcg | The same 100 mcg MK-7 dose at the lowest cost per day — a full year in one bottle. | $0.07 | Check price → |
| Best D3 + K2 | Sports Research Vitamin D3 + K2 | D3 + MK-7 | 5,000 IU + 100 mcg | Vegan D3 and MK-7 in one softgel — the pairing in a single daily pill. | $0.57 | Check price → |
| Most Complete | Life Extension Super K | K1 + MK-4 + MK-7 | 1,180 mcg K2 | Adds K1 and a little MK-4 on top of an effective MK-7 dose — it complements MK-7, it doesn't replace it. | $0.25 | Check price → |
| Higher Dose | NOW Foods Vitamin K2 (MK-7) 300 mcg | MK-7 (all-trans) | 300 mcg | Only worth the extra cost for the upper end of the studied 90–200 mcg range, or to split a bottle. | $0.32 | Check price → |
Why MK-7 — and why "all-trans" matters
Almost every K2 buying decision comes down to one thing: choose MK-7, not MK-4. MK-7 has a long half-life, so a single 90–200 mcg daily dose reaches and holds useful blood levels; MK-4 is cleared within hours and only worked in trials at a pharmaceutical 45 mg a day (taken as 15 mg three times daily). That's why the standalone supplements worth buying are MK-7. For the full pharmacology, see MK-7 vs MK-4.
The quality wrinkle is that MK-7 comes in an active all-trans form and a much less active cis form that contaminates cheap synthetic material. Branded, fermentation-derived ingredients like MenaQ7 are tested to guarantee all-trans content — which is why our top pick uses one. A label that says "all-trans" or names its ingredient brand is a genuine quality signal; a bargain MK-7 with neither is a gamble.
What to look for
- MK-7, not MK-4 — the practical form for daily supplementation.
- All-trans, ideally branded — look for "all-trans" or a named ingredient (MenaQ7). This is the single biggest quality differentiator.
- A trial-anchored dose — 90–200 mcg MK-7. 100 mcg is the sweet spot; 300 mcg sits at the upper studied range.
- Soy-free if you're allergic — natto-derived MK-7 can carry trace soy; chickpea-fermented options (like our top pick) avoid it.
- Pure MK-7 vs a blend — a standalone MK-7 is cleanest. Some products (like Life Extension Super K) add K1 — the form in leafy greens your liver uses for blood clotting — plus a little MK-4 on top; that's fine if you want fuller vitamin-K coverage, but the MK-7 is what does the bone-and-artery work. A D3+K2 combo is also fine if it fits your routine.
What we don't recommend
- Unbranded bargain MK-7 with no all-trans claim — you can't tell how much is the inactive cis form.
- Low-dose MK-4-only products — MK-4 doesn't accumulate at supplement doses; you'd need a pharmaceutical 45 mg regimen for the effect its trials showed.
- Anything promising to "clean out" or "reverse" arterial calcification — the recent hard-endpoint trials were negative. K2 supports the calcium-routing system; it doesn't dissolve existing plaque. See the honest evidence on the MK-7 vs MK-4 page.
- Starting K2 while on warfarin without your doctor — vitamin K opposes warfarin, and consistency of intake matters. This is a conversation with your prescriber, not a self-serve add-on.
Price check · Vitamin K2
What Vitamin K2 actually costs across the brands we track
What you pay. The 5 Vitamin K2 products here run $0.07 to $0.57 a day across 4 brands, a 8.1× gap. 0 of the 5 state some certification on the listing itself, which is a different and weaker claim than appearing in the registry above: one is what the Vitamin K2 label says, the other is what a certifier confirms.
Method: the 5 Vitamin K2 products in our catalogue, each priced at its own labelled serving rather than by pack size, across 4 brands. How we price.
The shelf · Vitamin K2
These Vitamin K2 servings are not comparable to each other
NOW Foods MK-7 Vitamin K2 100 mcg states 100 mcg a serving and Life Extension Super K states 1,180 mcg, both occupy one row of the same price column. So Nutricost Vitamin K2 MK-7 100 mcg showing 7¢ a day, the lowest here, may be reporting a smaller serving rather than a better price. Before comparing Nutricost Vitamin K2 MK-7 100 mcg with Sports Research Vitamin D3 + K2, check what each calls a serving.
Method: the 5 Vitamin K2 products above, compared on label facts, serving size, servings per container, form, price. Not a dosing recommendation.
Frequently Asked Questions
What is the best vitamin K2 supplement?
For most people the best vitamin K2 is a standalone all-trans MK-7 at the clinical 100 mcg dose. Our top pick is NOW Foods MK-7 100 mcg, which uses the branded MenaQ7 ingredient (all-trans, soy-free) at about $0.22 a day. For the lowest cost, Nutricost MK-7 100 mcg is about $0.07 a day. If you want vitamin D in the same pill, Sports Research D3 + K2 pairs 5,000 IU of D3 with 100 mcg of MK-7. Choose MK-7 over MK-4, and look for an all-trans label.
Should I take a D3 and K2 combo or separate supplements?
Either works. A combo is convenient and reflects the mechanistic pairing (vitamin D raises calcium absorption; K2 helps route that calcium into bone). But the "45 mcg K2 per 1,000 IU D3" ratio printed on combos is a formulation convention, not a validated dose — so a combo is not medically superior to taking a 90–200 mcg MK-7 separately. Pick a combo for convenience, or separate products if you want to control each dose independently.
How much vitamin K2 should I take per day?
A trial-anchored MK-7 dose is 90–200 mcg per day; the 3-year trials used 180 mcg. There is no established upper limit for vitamin K. Take it with a fatty meal. The one hard rule: if you take warfarin or another vitamin K antagonist, do not start K2 without your physician. See our MK-7 vs MK-4 guide for the full dosing breakdown.
What does "all-trans" MK-7 mean on a label?
MK-7 exists as an active all-trans form and a much less active cis form that can contaminate cheap synthetic material. All-trans is the form used in the clinical trials and the one you want. Branded, fermentation-derived ingredients like MenaQ7 are tested to guarantee all-trans content; a label that says "all-trans" or names a branded ingredient is a good quality signal.
Related Guides
- MK-7 vs MK-4 — Which form, how much, and the honest evidence on arteries
- All Vitamin K2 Guides
- Vitamin D with K2 — Whether you need the pairing
- Best Vitamin D Supplement — The other half of the combo
Sources
- Sato T, et al. "Comparison of menaquinone-4 and menaquinone-7 bioavailability in healthy women." Nutr J. 2012;11:93. PMID: 23140417
- Schurgers LJ, et al. "Vitamin K-containing dietary supplements: synthetic K1 vs natto-derived MK-7." Blood. 2007;109(8):3279-83. PMID: 17158229
- Knapen MHJ, et al. "Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women." Osteoporos Int. 2013;24(9):2499-507. PMID: 23525894
- Cirilli I, et al. "Carboxylative efficacy of trans and cis MK7." Biofactors. 2022;48(5):1058-1066. PMID: 35583412
- NIH Office of Dietary Supplements. "Vitamin K: Fact Sheet for Health Professionals." ods.od.nih.gov