MK7 Vitamin K2: Benefits, Food Sources, Dosage, and Safety

“MK7 vitamin” usually means vitamin K2 in the MK-7 form. You might see it on supplement labels next to claims about bones and heart health. But what is it, what does it do, and do you need it?

This guide breaks MK-7 down in plain English. You’ll learn what it does in the body, how it differs from other forms of vitamin K, which foods contain it, how people use it with vitamin D, and how to think about dose and safety.

What is MK7 vitamin?

Vitamin K is a family of nutrients that help your body use calcium in the right places and support normal blood clotting. There are two main types:

• Vitamin K1 (phylloquinone), found mostly in leafy greens
• Vitamin K2 (menaquinones), found in fermented foods and some animal foods

MK-7 is a specific type of vitamin K2. The “MK” stands for menaquinone, and “7” describes its structure. That detail matters because structure affects how long it stays in your blood and how your body uses it.

MK-7 vs K1 and other K2 forms: what’s the difference?

Most people get vitamin K1 from food without trying. K1 plays a big role in normal clotting. K2 forms (including MK-4 and MK-7) also support clotting, but they’re often discussed more for bone and artery health because they activate proteins that manage calcium.

MK-7 tends to last longer in the body

Compared with MK-4, MK-7 generally has a longer half-life. In simple terms: it stays around longer after you take it, which may allow steadier levels from a once-a-day dose. That’s one reason MK7 vitamin K2 shows up so often in supplements.

K1 is common in food; MK-7 is less common

K1 is abundant in spinach, kale, and other greens. MK-7 is most famous for coming from natto, a fermented soybean food eaten in Japan. If you don’t eat natto or other fermented foods, you may get very little MK-7 from diet alone.

For a clear overview of vitamin K forms and their roles, see the NIH Office of Dietary Supplements consumer fact sheet on vitamin K.

What does MK7 vitamin do in the body?

MK-7 helps “turn on” (activate) certain proteins that need vitamin K to work. Two of the most talked-about are:

• Osteocalcin, which helps bind calcium in bone
• Matrix Gla protein (MGP), which helps regulate calcium in blood vessel walls

That’s the basic reason you’ll hear MK7 vitamin K2 linked with bone strength and arterial health. It doesn’t “remove” calcium from arteries like a drain cleaner. It supports normal biology that helps keep calcium where it should be.

MK-7 and bone health: what the research suggests

Bone health comes down to more than calcium. Your body also needs vitamin D, protein, resistance exercise, and enough overall calories. Vitamin K2 fits into this picture because activated osteocalcin supports bone mineralization.

Several studies have looked at K2 and bone markers, bone density, and fracture risk, with mixed results depending on the population and the form of K2 used. If you want to read a detailed, research-based review, the Linus Pauling Institute’s vitamin K overview explains mechanisms, food sources, and study findings in depth.

Who might care most about MK-7 for bones?

• Adults who avoid leafy greens and fermented foods
• Older adults focused on maintaining bone mass
• People taking vitamin D long term who want to cover the basics for calcium handling

Still, don’t treat MK-7 as a substitute for proven bone steps like strength training, adequate protein, and enough vitamin D.

MK-7 and heart health: what people mean (and what they don’t)

You’ll often see claims that MK7 vitamin supports “arterial health.” The idea centers on MGP, a vitamin K-dependent protein involved in managing calcium in vessel walls.

Here’s the practical takeaway: MK-7 supports the activation of proteins linked to normal calcium metabolism. That’s not the same as saying it prevents heart disease. Heart health depends on many factors, including blood pressure, cholesterol, smoking, diabetes, sleep, and activity.

If you want a grounded look at what mainstream medicine says about vitamin K, including cautions for people on blood thinners, the Cleveland Clinic’s vitamin K explainer is a solid starting point.

Food sources of MK7 vitamin (and other K2 forms)

If you’d rather get nutrients from food first, that’s reasonable. The catch is that MK-7-rich foods are not staples in many diets.

Top food source: natto

Natto is the standout. It’s fermented soybeans with a strong smell and sticky texture. People tend to love it or hate it. If you can tolerate it, a small serving can provide a lot of MK-7.

Other foods that provide vitamin K2 (mostly not MK-7)

• Hard and aged cheeses (amounts vary by type)
• Yogurt and kefir (some K2, varies)
• Egg yolks
• Liver and some other organ meats
• Fermented foods like sauerkraut (usually modest K2 compared to natto)

Food amounts vary a lot based on fermentation method, animal feed, and processing. If you’re trying to increase K2 from food, focus on consistent habits you’ll keep: a daily serving of fermented dairy, a few eggs per week, or natto if you can handle it.

MK-7 supplements: what to look for

Walk into any supplement aisle and you’ll see “K2” everywhere. Labels can be confusing, so here’s what helps.

Check the form: MK-7 vs MK-4

Some products say “vitamin K2” but don’t list the form. If you specifically want MK7 vitamin K2, look for “menaquinone-7” or “MK-7” on the Supplement Facts panel.

Check the dose in micrograms (mcg)

MK-7 doses often appear as 90 mcg, 100 mcg, 120 mcg, or 180 mcg. You don’t need megadoses for most goals people talk about online.

Look for third-party testing

Supplements can vary in quality. Look for brands that use independent testing. A practical way to vet products is the ConsumerLab supplement testing reports (paid resource). It’s not perfect, but it’s better than guessing based on marketing.

MK-7 and vitamin D: why people pair them

Vitamin D helps your gut absorb calcium. Vitamin K helps activate proteins that guide calcium into bones and away from soft tissues. That’s why many people take them together.

This pairing doesn’t mean you must take both. It means you should think about your full “calcium system” instead of chasing one nutrient at a time.

Simple, practical combo approach

• If you take vitamin D daily, consider whether you also get enough vitamin K from food
• If your diet lacks leafy greens and fermented foods, MK-7 may fill a gap
• If you already eat lots of greens, you may be covering much of your vitamin K needs through K1

If you want a quick check on how much vitamin D you might need based on age and other factors, use a practical tool like the calcium intake calculator from the International Osteoporosis Foundation and discuss vitamin D targets with your clinician. (The calculator focuses on calcium, but it helps you see whether your base diet supports your plan.)

How much MK7 vitamin should you take?

There’s no single “right” dose for everyone, and official daily values don’t separate K1 from K2. Most MK-7 supplements land in a range that matches how they were used in many studies and consumer products.

Common supplemental amounts

• 90-120 mcg daily is a common maintenance range
• 180 mcg daily is also common, especially in bone-focused formulas

Take it with a meal that contains some fat. Vitamin K is fat-soluble, so your body absorbs it better with food than on an empty stomach.

Should you test anything first?

There’s no routine “MK-7 level” test used in standard care. If you’re focused on bone, the most useful medical data points are still basics like vitamin D (25-OH), bone density scans when appropriate, and overall diet and exercise habits.

Safety, side effects, and who should avoid MK-7

For most healthy adults, MK7 vitamin K2 at typical supplement doses has a good safety record. Side effects are uncommon and often mild when they happen (stomach upset is the one people report most).

If you take warfarin (Coumadin), talk to your prescriber

This part matters. Warfarin works by interfering with vitamin K. Big swings in vitamin K intake can change how warfarin works.

• Don’t start MK-7 supplements without medical guidance if you take warfarin
• If your clinician approves vitamin K intake, aim for consistency day to day

For an accessible overview of how vitamin K interacts with blood thinners, see the NHS warfarin guidance.

Pregnancy, breastfeeding, and medical conditions

Food sources of vitamin K are normal parts of a healthy diet. For supplements, check with a clinician if you’re pregnant, breastfeeding, have liver disease, or take medicines that affect clotting.

Action plan: should you add MK7 vitamin to your routine?

If you want a simple way to decide, use this short checklist.

Step 1: Look at your food first

• Do you eat leafy greens most days? That supports vitamin K1 intake.
• Do you eat fermented foods or aged cheese often? That may add some K2.
• Do you eat natto? If yes, you may already get meaningful MK-7.

Step 2: Check your vitamin D habit

• If you supplement vitamin D and your diet is low in vitamin K foods, MK-7 may make sense.
• If you don’t supplement vitamin D and rarely get sun, start by checking your vitamin D status with your clinician.

Step 3: Make one change you’ll keep

• Food-first option: add one K2-friendly food you enjoy and will eat weekly.
• Supplement option: choose a reputable MK-7 product in the 90-180 mcg range and take it with a meal.
• Movement option: add two strength sessions per week. It does more for bones than any single supplement.

Common questions about MK7 vitamin

Is MK-7 the same as vitamin K?

No. MK-7 is one form of vitamin K2. Vitamin K also includes K1 and other K2 forms such as MK-4.

Can I take MK-7 with calcium?

Many people do. Calcium supports bone structure, while vitamin D and vitamin K help the body handle calcium well. Still, total calcium intake matters more than timing. Aim to meet your needs from food first, then fill gaps if needed.

Do I need MK-7 if I eat lots of greens?

You may already get plenty of vitamin K1. Whether you benefit from added MK-7 depends on your diet, health goals, and medical context. If you’re curious and not on warfarin, a moderate dose is a common approach, but it’s not mandatory.

Conclusion

MK7 vitamin K2 gets attention for a reason: it supports key proteins that help your body use calcium in a normal, healthy way. Food sources exist, but MK-7 itself mainly comes from natto and certain fermented foods, so supplements can be a practical option for some people.

If you want the best payoff, treat MK-7 as part of a bigger plan: eat well, lift weights, get enough vitamin D, and keep your calcium intake sensible. And if you take warfarin, don’t guess. Ask your prescriber and keep your vitamin K intake steady.