Introduction

Vitamins and minerals are essential elements for maintaining a healthier and more energetic body. They are important because some of them help the body resist infection, aid in energy production from food, and others contribute to blood clotting, among other benefits.¹

One of these essential vitamins is vitamin K, which plays a vital role in the formation of blood clots and maintaining bone health; therefore, it is necessary in reducing the risk of osteoporosis and coronary artery disease. 

It is crucial to take a sufficient daily amount of it as our intestines produce some vitamin K, and you can also get it from food like green leafy vegetables, meat, eggs, and fruits like blueberries.²

Here at Klarity, we will discuss the importance of blueberries as a source of vitamin K and compare the amount of vitamin K in them with that in other foods rich in vitamin K.

What is vitamin K? And what are its types?

Vitamin K is a fat-soluble vitamin essential for maintaining healthy blood and bones, and can be obtained from food or as a nutritional supplement. There are two types: ³

1. Vitamin K1, also known as phylloquinone, is found in green, leafy vegetables such as spinach and broccoli.
2. Vitamin K2, called menaquinones, is primarily produced in our gut and found in reasonable amounts in animal food and fermented products. Phylloquinone can be converted into menaquinone-4 (MK-4) through a conversion process that does not require bacterial action.

Functions of vitamin K in the body⁴

Vitamin K is an essential vitamin for our body because it plays a critical role in blood clotting, maintaining bone health, and reducing the risk of osteoporosis.

1. Blood clotting
   1. Vitamin K helps produce 13 proteins, which are vital for coagulation, as this process is crucial for stopping bleeding after injuries or wounds
   2. On the other hand, be cautious when taking warfarin or any other anticoagulant medication, as consuming a large amount of vitamin K as a supplement or from food can reverse its action
2. Bone health
   1. Vitamin K is crucial for maintaining bone health because it helps produce osteocalcin, a vital protein that helps prevent low bone density. It may help decrease the risk of bone fractures, and in some studies, it may be used in combination with other treatments for osteoporosis

Dietary sources of vitamin K³

1. You can obtain vitamin K from various food sources. Studies have found that vitamin K1 (phylloquinone) can be obtained primarily from green, leafy vegetables, such as spinach and broccoli, as well as from vegetable oils and certain fruits, including blueberries. But in meat, egg, dairy products, and fermented foods like cheese, we found low levels of phylloquinone and a modest amount of menaquinones
2. There is a difference in the bioavailability of vitamin K. When phylloquinone is taken in its free form, not in food, its absorption is approximately 80%. However, when phylloquinone is consumed in food, absorption is significantly lower. Nonetheless, when we consume oils or foods rich in fats along with vegetables, it increases the absorption of phylloquinone from vegetables by only 4% to 17%
3. This table shows some examples of food rich in vitamin K:

Overview of blueberries as a nutrient-rich fruit⁵

Blueberries are a fruit with numerous benefits for humans. Therefore, it contains a variety of essential elements and vitamins for our health and body, such as ascorbic acid, vitamin K, vitamin B9, magnesium, and dietary fibre. Because it contains all these elements, it has several benefits for our bodies.

Beneficial effects of blueberry fruit 

1. Blueberries possess antioxidant properties, primarily due to their anthocyanin, along with other polyphenols, which play a role in protecting against diabetes, cancer, cardiovascular disease, and neurodegenerative diseases⁶
2. It contains several types of vitamins and minerals, and it is considered a good source for:⁷
   1. Vitamin C: 24%
   2. Vitamin K: 36%
   3. Manganese: 25%
   4. Dietary fibre: 14%

3. It helps to reduce cholesterol because it contains soluble fibres which bind with bile in our gut to easily remove these waste products, which include cholesterol, bilirubin, bile acids, and salts, so help our body to remove these materials easily⁷
4. It also helps manage blood sugar, as it contains a large amount of fibre and low sugar, making it suitable for patients with diabetes

The relation between blueberries and vitamin K⁷

Blueberries are rich in vitamin K, so you can add them to your diet as a source of this vitamin to meet the daily intake requirement. Blueberries contribute to blood clotting and bone health due to their high vitamin K content.

Summary

 In this article, we discuss vitamin K and its importance for maintaining our blood and bone health. We talked about blueberry fruit and its significance as a good source of vitamin K. How it affects our blood clotting function and our bone health so, in the end, I advise you, Dear reader, to keep taking a healthy diet contains all vitamins and minerals necessary for your body and be aware of the effect of vitamin K on the action of the anticoagulant drugs and consult your physician if you take both of them together to make him tell you the amount needed to take from vitamin K not to affect action of these drugs. 

FAQs

What is the primary purpose of vitamin K in the blood?

Vitamin K is vital for our blood and bone health because it helps produce several proteins essential for blood clotting and bone formation. These proteins, such as prothrombin, a vitamin K-dependent protein crucial for blood clotting, and osteocalcin, another protein that relies on vitamin K for healthy bone tissue, are examples.

Do blueberries contain vitamin K?

Yes, blueberries contain 29 mcg of vitamin K per serving.

Are blueberries blood thinners?

All blueberries are blood thinners, which is required in thrombotic disorders. 

Does vitamin K reduce calcium in the blood?

Vitamin K is essential in reducing calcium in our blood, decreasing the deposition of calcium in vessels, and reducing arterial calcification.

Do blueberries help with blood clotting?

Blueberries can help in blood clotting because they contain a sufficient amount of vitamin K, which is vital in the production of prothrombin, which is essential for blood clotting functions.

What happens if vitamin K is low?

Vitamin K deficiency can lead to bleeding, osteoporosis, and bone problems, as well as an increased risk of cardiovascular diseases, because vitamin K is essential for the production of vital proteins that support bone and blood health. 

Should I take D3 and K2 simultaneously?

Studies have shown that taking vitamin K and D together is beneficial for supporting heart and bone health.