KEY TAKEAWAYS:
- Vitamin K1 mainly supports blood clotting and is found in leafy green vegetables.
- Vitamin K2 is found in fermented foods and certain animal products.
- Both types play roles in bone health, but their functions and food sources differ.
- A balanced diet is a good starting point, and research on K2 supplements is still ongoing.
Most people have heard of vitamin K. But not everyone knows it comes in more than one type. Vitamin K1 is mostly found in leafy greens. Vitamin K2 comes from foods such as fermented soybeans, cheese and eggs. Both matter, but they work in slightly different ways.
You may ask, "Does the difference really matter?" Let's find out. From food sources to bone health and blood clotting, here is what you should know about vitamin K1 vs K2.
What Is Vitamin K?
Vitamin K is a fat-soluble vitamin. It helps your body switch on proteins it needs to work well. These proteins help stop bleeding and support your bones. They also help control how minerals settle in some tissues.
Vitamin K1
Vitamin K1, also called phylloquinone, comes mainly from plants. Leafy greens are rich in it, so K1 is easy to get from daily meals.
Vitamin K2
Vitamin K2, also called menaquinone, is found in some fermented foods and animal products. It has several forms, such as MK-4 and MK-7. They act differently in the body.
Vitamin K3 is man-made. It is not a standard dietary vitamin for people.
So, what sets K1 apart from K2?
Vitamin K1 vs K2: What Is the Difference?
When it comes to vitamin K1 vs K2, both help your blood clot. Researchers are also studying their effects on bone and heart health.
| Feature | Vitamin K1 | Vitamin K2 |
| Scientific name | Phylloquinone | Menaquinones |
| Main sources | Green leafy vegetables and plant oils | Fermented foods and some animal products |
| Common forms | Phylloquinone | MK-4, MK-7 and others |
| Blood clotting | Supports normal clotting | Supports normal clotting |
| Bone health | Activates proteins involved in bone metabolism | Activates proteins involved in bone metabolism |
| Time in the bloodstream | Generally shorter | Varies by form |
Your body absorbs both forms with the help of dietary fat. But how long each one stays in your blood can differ.
For example, MK-7 stays in your blood longer than K1 and MK-4. That does not mean it works better for every health goal.
What Does Vitamin K1 Do?
Vitamin K1 is the main form of vitamin K in many diets. Its best-known job is to switch on proteins for blood clotting.
For example, your finger has an injury. Your body starts a chain of steps to stop the bleeding. Vitamin K helps switch on several proteins in that chain. Without enough vitamin K, clotting may not work normally.
K1 also helps activate osteocalcin, a protein that plays a part in bone metabolism. This helps your body maintain and renew bone.
But healthy bones need more than one nutrient. Calcium, vitamin D, exercise and a balanced diet all help too. For bone health, vitamin K1 vs K2 is only part of the story.
What Does Vitamin K2 Do?
Vitamin K2 helps activate some of the same proteins as K1. Researchers also ask if certain K2 forms give extra benefits for bones and the heart.
1. Supports bone metabolism
K2 helps activate osteocalcin too. Studies have checked if K2 supplements raise bone density or lower the risk of fractures. But the results do not show that everyone benefits. We need more research to learn who may gain, and why.
2. Helps control mineral build-up
Vitamin K2 also helps activate matrix Gla protein. This protein helps control how minerals settle in soft tissues. Researchers want to know if this helps the heart. But a good theory is not proof. Current evidence does not show that K2 supplements prevent heart disease.
Does the Form of K2 Matter?
Yes. MK-4 and MK-7 differ in their sources and in how they act in the body.
MK-4 is found in some animal foods. MK-7 is linked to fermented foods like natto. MK-7 stays in the blood longer. But a longer stay does not guarantee better health results. The benefit of a supplement depends on the condition studied and how strong the evidence is. So in the vitamin K1 vs K2 question, the form of K2 adds one more layer.
Where Can You Find Vitamin K1 and K2?
You can get vitamin K from everyday foods. In Malaysia, common vegetables, eggs, fish and chicken make this easy. The food lists for vitamin K1 vs K2 look quite different.
Foods Rich in Vitamin K1
Vitamin K1 is found mainly in green leafy vegetables and some plant oils. Many vegetables used in Malaysian cooking can add to your intake.
Good sources include:
- Bayam, or spinach
- Sawi, or mustard greens
- Kangkung, or water spinach
- Broccoli
- Cabbage
- Salad greens
- Soybean oil
- Canola oil
Do you need to eat a mountain of bayam every day? No. Your usual sayur dish works well. Add leafy vegetables to nasi campur, stir fries or soups.
Foods Rich in Vitamin K2
Vitamin K2 is found in some fermented foods and animal products. Some are common in Malaysia, but their K2 content can vary a lot.
Good sources include:
- Natto, made from fermented soybeans
- Egg yolks
- Chicken and other meats
- Certain fish and other animal foods
- Some dairy products, such as cheddar and full-fat dairy
Natto is very rich in K2. But its sticky texture and strong smell do not suit everyone. Aged cheeses are another option. Their K2 level depends on the type and how they are made.
Not everyone wants natto for breakfast, right? You can eat a varied diet without forcing down foods you dislike.
IMPORTANT:
Not every fermented food is rich in K2. Ordinary tofu and soy milk are not big sources by default. Their K2 content depends on how they are made.
Should You Take a Vitamin K Supplement?
"Do I need a supplement?" is a fair question. For most people, food is a good place to start. Whether you need a supplement depends on your diet, health and personal needs.
Some studies suggest K2 supplements may help certain bone measures. But the evidence does not show that everyone needs extra K2, or that it prevents heart disease.
If you want a supplement for a health concern, talk to a healthcare professional. This matters most if you take medicine that affects blood clotting.
Warfarin is one example, because vitamin K changes how it works. If you take warfarin, keep your vitamin K intake steady. Follow your healthcare team's advice.
More supplements do not mean better health, right? Ask yourself if you truly need one first.
How Much Vitamin K Do You Need Daily?
Your daily needs depend on your age and other factors. In the UK, the advised intake for adults is one mg per kg of body weight each day.
For example, an adult who weighs 60 kg needs 60 mg daily. This guideline does not split vitamin K1 vs K2 into separate amounts. It covers vitamin K overall.
Most people get enough vitamin K from a varied diet. But some health conditions can affect how well your body absorbs nutrients.
The Bottom Line
In the vitamin K1 vs K2 comparison, both are important, but they play different roles. K1 is mainly found in leafy greens. K2 is found in fermented foods and some animal products. Both are linked to bone health, but research on K2 supplements is still ongoing. For most people, a balanced diet is a good place to start.
Thinking about a supplement? Nano Singapore Vitamin K2 + D3 Complex combines two nutrients for bone health. Vitamin D3 helps your body absorb calcium. Vitamin K2 supports proteins that keep bones healthy. Together, they are an easy way to get both each day.
Can you take vitamin K1 and K2 together?
You can get both forms from food. Whether you need supplements depends on your own needs and medicines. See a doctor first if you take warfarin.
Is vitamin K2 better than K1 for bone health?
Not always. Both help activate proteins linked to bone metabolism. Research on K2 supplements continues. Current evidence does not show that K2 is better for everyone.
Does vitamin K2 prevent heart disease?
There is not enough evidence to say that K2 supplements prevent heart disease. Researchers are studying how K2 helps control minerals in the body, but we need more clinical research.
References:
Ma, M., Ma, Z., He, Y., Sun, H., Yang, B., Ruan, B., Zhan, W., Li, S., Dong, H., & Wang, Y. (2022). Efficacy of vitamin K2 in the prevention and treatment of postmenopausal osteoporosis: A systematic review and meta-analysis of randomized controlled trials. Frontiers in Public Health, 10, Article 979649. https://doi.org/10.3389/fpubh.2022.979649
National Institutes of Health, Office of Dietary Supplements. (2021, March 22). Vitamin K: Fact sheet for consumers. https://ods.od.nih.gov/factsheets/VitaminK/Consumer/
Vlasschaert, C., Goss, C. J., Pilkey, N. G., McCormick, N. J., & Holden, R. M. (2020). Vitamin K supplementation for the prevention of cardiovascular disease: Where is the evidence? A systematic review of controlled trials. Nutrients, 12(10), Article 2909. https://doi.org/10.3390/nu12102909
