Vitamin K2: MK-7 vs MK-4

If you have seen vitamin D3 and K2 sold together and wondered why, this page is for you. It explains how K2 differs from the K1 in leafy greens, what MK-7 and MK-4 mean, the EU reference amount, and the one medicine interaction everyone should know about.

By the Healthana Editorial Team · Last reviewed: 01 Nov 2026

What vitamin K2 is and what it does

Vitamin K is a group of fat-soluble compounds. Vitamin K1 (phylloquinone) comes mainly from green leafy vegetables. Vitamin K2 is a family of related compounds called menaquinones, written as MK-4 to MK-13, found in fermented foods and some animal products; gut bacteria also make small amounts. Both K1 and K2 count as vitamin K on EU labels.

Vitamin K is needed to activate proteins involved in blood clotting and proteins found in bone. That is the background to the two EU-authorised wordings shown in the claims box below, which apply to vitamin K in general. Studies have looked at whether K2 behaves differently from K1 in the body, but these differences are not reflected in any separate authorised claim.

Forms you'll see on labels

Find this form at Healthana

Examples from our shelves for some of the forms in the table above.

D3 + K2 combinationsNOW Vitamin D-3 & K-2 1,000 IU / 45 mcg, 120 Vegetable CapsulesBHD13.910D3 + K2 combinationsORZAX Vitamin D3 with K2 Drops 1000 IU, 20mlBHD8.220Calcium + D3 + K2Fiterman Pharma Ostart Plus Ca + K2 + D3, 20 TabletsBHD5.020

How much vitamin K: NRV, typical amounts and upper limit

• EU NRV: 75 µg of vitamin K a day (K1 and K2 combined).
• Common supplement amounts: 10–25 µg in multivitamins and drops; 45–100 µg of MK-7 in D3 + K2 products; some K2-only products contain 100–200 µg.
• Upper limit: EFSA has not set an upper limit because data were not adequate to derive one. UK guidance says that 1 mg (1,000 µg) or less a day from supplements is unlikely to cause harm.

Vitamin K1 sources include spinach, kale, molokhia, lettuce, broccoli, cabbage, parsley and plant oils. K2 sources include natto, hard and soft cheeses, egg yolks and chicken, plus other fermented foods. A varied diet usually covers vitamin K needs. Browse vitamin D products, which K2 is often paired with, in our vitamin D collection.

Who should check with a doctor or pharmacist first

• Anyone taking warfarin or other vitamin K antagonist blood thinners. This is the most important interaction. Vitamin K works directly against these medicines, and a change in vitamin K intake can alter how well they work, raising the risk of bleeding or clotting. Do not start, stop or change a vitamin K or K2 product without talking to the clinic that monitors your blood tests. People on other types of blood thinner should also ask first.
• People taking long courses of antibiotics, bile acid sequestrants such as cholestyramine, or orlistat, which can lower vitamin K levels.
• Anyone with a condition affecting fat digestion or the liver, or who has had bariatric surgery.
• Pregnancy and breastfeeding: check with your doctor before adding a separate K2 product to a pregnancy multivitamin.
• Children: check the age on the pack and ask a doctor or pharmacist; some D3 + K2 drops are made for adults only.

How to read a vitamin K2 label

1. Look for the form: "menaquinone-7" or "MK-7", "MK-4", or "phylloquinone" for K1.
2. Check µg per serving: drops can contain very small amounts per drop, for example around 11 µg, so several drops may be needed to reach the NRV.
3. Read the %NRV: 75 µg is 100% NRV, so a 45 µg capsule shows 60%.
4. In combination products, read the vitamin D3 and calcium lines too, and add them to any other products you take.
5. Note the oil base in drops and softgels, which matters for storage.

Bahrain and GCC notes

Leafy dishes such as molokhia and fresh herbs are rich in vitamin K1. If you take warfarin, try to keep your intake of these foods steady, including during Ramadan, when eating patterns change, and tell your clinic about any new supplement. Store oil-based drops and softgels below 25°C and out of direct sunlight. Browse related products in our vitamin D collection.

Label check

Reading a real label

NOW Vitamin D-3 & K-2 1,000 IU / 45 mcg, 120 Vegetable Capsules

On the label	What it means
45 mcg vitamin K-2	60% NRV, against the 75 µg vitamin K reference intake
As menaquinone	The K2 family; MK-7 is the most common type
1,000 IU (25 mcg) vitamin D-3	500% NRV, a quarter of EFSA's 100 µg adult upper limit
1 to 2 a day with meals	Using blood thinners? Ask your doctor before any vitamin K

Figures from the product's own label. Always check the pack in your hand.See this product

Products with Vitamin K2

Always read the label and check the amount per serving.

NOWNOW Vitamin D-3 & K-2 1,000 IU / 45 mcg, 120 Vegetable CapsulesBHD13.910ORZAXORZAX Vitamin D3 with K2 Drops 1000 IU, 20mlBHD8.220Fiterman PharmaFiterman Pharma Ostart Plus Ca + K2 + D3, 20 TabletsBHD5.020

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