Best vitamin K supplement


Vitamin K was discovered by Danish scientist Henrik Dam in 1929 when he noticed that his chicken subjects were bleeding, which was later discovered to be due to low levels of vitamin K.

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Which vitamin K supplement is best?

Vitamin K is one of the fat-soluble vitamins. Its primary functions include supporting healthy bones, skin and soft tissues, boosting calcium absorption and speeding up wound healing.

When choosing a vitamin K supplement, always select one that provides highly-absorbable vitamin K to your body, like the California Gold Nutrition Full Spectrum Vitamin K2, which ensures efficient delivery of the vitamin to the bones and soft tissues.

What to know before you buy a vitamin K supplement


While there are several types of vitamin K, the two primary forms are vitamin K1 and vitamin K2. When you consume leafy green vegetables, the vitamin K in this food source is vitamin K1. Vitamin K2, on the other hand, is found in fermented food and animal products. The difference between these two types of vitamin K is their absorption and transport to the tissues. Although vitamin K1 is poorly absorbed in the body, not much is known about the absorption rate of vitamin K2. It is believed that the latter is better absorbed than the former. When choosing your vitamin K supplement, you can find either of these types available, so you can always choose the option you prefer.


Vitamin K plays a critical role in blood clotting and strengthening of the bones because it helps the body produce prothrombin, which is essential for blood clotting and bone metabolism. While most adults are not at risk of vitamin K deficiency, newborns and individuals with malabsorption issues may have low levels of vitamin K. 

Apart from its function in bone health and blood clotting, vitamin K is also important in heart health. For instance, vitamin K may lower your blood pressure because of its mineralization function, which prevents the buildup of minerals in the arteries.


Most people get the vitamin K they need from their diet, and the recommended daily allowance ranges from as low as 4 mg in children to as high as 19 mg in lactating women. If you have to take a vitamin E supplement, ensure the amount of vitamin E in the formulation meets your recommended daily requirement. Some vitamin E supplements also include the dosage in terms of international units. Suppose you want to convert from mg to IU. In that case, the value of 1 mg of vitamin E equals 1.49 IU of the natural form or 2.22 IU of synthetic vitamin E, so you can use this information when doing your conversion. 

What to look for in a quality vitamin E supplement

Drug interactions

Taking vitamin K with blood thinners, cholesterol-lowering drugs or weight-loss drugs can lead to complications. For instance, a blood thinner like warfarin can reduce the clotting ability of vitamin K. If you are on weight-loss drugs or cholesterol-lowering medications have been linked with the depletion of vitamin K, so you may have to take vitamin K supplement if you are using any of these medications.


If you have had a stroke in the past or you are prone to blood clots, you should discuss with your doctor before taking vitamin K. If you are pregnant, you should also ensure that you don’t take more than your recommended daily allowance of vitamin K. However, if you’re pregnant and taking an anticonvulsant medication like phenytoin, you may need vitamin K supplementation before delivery because your anticonvulsant drug may increase your risk of vitamin K deficiency.


Vitamin E is available as a supplement in different forms, from soft gel capsules to powder and oil. If you want to measure the exact amount of vitamin E you intend to take, using the powder form is a great way to get it right. However, if you prefer the convenience of pills or capsule forms, taking this dosage form will be a better option than the powder. In the oil form, you can use vitamin E as a topical solution that can serve as a skin moisturizer.


Some vitamin K supplements may contain ingredients that you may want to limit in your diet. For example, some products contain gelatin, silicon dioxide or soybeans, which may cause unwanted side effects in some people. Some options include other vitamins in the formulation like calcium, vitamin C and vitamin D3. So it is essential to check the ingredients to ensure you aren’t taking a product that you’re looking to avoid.

How much you can expect to spend on a vitamin K supplement

If you want to buy a bottle of vitamin K supplements, you should expect to pay 14-30 cents per pill. However, vitamin K supplements that contain other vitamins like D3 can cost up to $1 per pill. If you choose to buy the liquid vitamin K, expect to pay $20-$40 for a one-ounce bottle.

Vitamin K supplement FAQ

Is there any risk of taking a vitamin K supplement daily?

A. Taking vitamin K daily for up to two years is safe because, unlike other fat-soluble vitamins, vitamin K doesn’t accumulate to toxic levels in the body even when taken in excess amounts. Instead, it is broken down quickly and eliminated through urine or stool.

What drugs should I not take with my vitamin K supplement?

A. Vitamin K interacts with many drugs, including antacids, blood thinners and antibiotics. Before you start taking a vitamin K supplement, you should discuss it with your doctor.

What’s the best vitamin K supplement to buy?

Top vitamin K supplement

California Gold Nutrition Vitamin K2

California Gold Nutrition Vitamin K2

What you need to know: It contains a blend of menaquinone compounds, which is the highly absorbable form of vitamin K.

What you’ll love: It is vegan friendly and doesn’t contain soy and gluten ingredients. The supplement is also produced in a third-party tested, cGMP registered facility.

What you should consider: Some users mentioned that it worked better when combined with vitamin D.

Where to buy: Sold by Amazon

Top vitamin K supplement for the money

Now Foods Vitamin K2

Now Foods Vitamin K2

What you need to know: Formulated with the potent vitamin K2, this supplement helps maintain your bone, cardiovascular and nervous system health.

What you’ll love: It is free of gluten, soy and wheat, so you don’t have to worry if you are allergic to these ingredients. The supplement is also made in a GMP-certified facility to ensure it is produced to meet the highest standard of purity and quality.

What you should consider: The color of some of the soft gel capsules may slightly differ from one another, but this is completely normal.

Where to buy: Sold by iherb 

Worth checking out

Elderberry Hill Organics Vitamin K Liquid Drops

Elderberry Hill Organics Vitamin K Liquid Drops

What you need to know: This vitamin K liquid drop is designed to maintain optimal bone health and reduce osteoporosis and fracture risk.

What you’ll love: It is portable and easy to use or administer. It is vegan friendly and doesn’t contain added sugar, gluten or nuts that may cause allergies. It is made for the whole family as it is suitable for all ages.

What you should consider: Some users complained about the bottle’s small size, so you may need to refill often.

Where to buy: Sold by Amazon


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Ayotola Ogunsipe writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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