Choose Natural Vitamin K

Only 5-10% of vitamin K1, from foods such as eggs, green vegetables and carrots, is taken up in the blood and is converted to vitamin K2 in the liver. Vitamin K2 is necessary for, amongst other things, strong bones.

Text Doctor Carsten Vagn-Hansen

Vitamins are essential nutrients. Even if we only need small amounts of them is the body not able to produce or produce enough of all of them. In this article we will focus on vitamin K.

The K comes from the German word for coagulation. It was discovered by the Danish biochemist Henrik Dam in 1934, which he received the Nobel price for in 1943. Vitamin K has several important functions.

The Following K Vitamins Exists:

  • Vitamin K1, Fyllokinon (natural)- dissolves in fat
  • Vitamin K2, Manakinon (natural) – dissolves in fat
  • Vitamin K3, Menadion (artificial) – dissolves in water

The Natural Vitamins K1 and K2

Vitamin K1 exists in green vegetables such as broccoli, spinach, lettuce, parsley and all cabbage species, as well as peas, avocados, carrots, cheese, butter, eggs, potatoes, fruit and berries. This vitamin can also be found in olive oil, soya oil and rapeseed oil. Only 5-10% of vitamin K1 is taken up in the blood together with fat from food. Thereafter it is converted to vitamin K2, this happens preferably in the liver. The conversion is inhibited significantly if one has a bad liver. K2 is formed by bacteria in the large intestine, but in smaller amounts than previously assumed. Margarine and other hydrogenated vegetable fats (hydrogenated oil) may reduce absorption and the biological effect of vitamin K2. A dish that contains lots of vitamin K2 is “Natto” (steamed and fermented soybeans), which is a traditional Japanese breakfast and “samurai food”. This is said to play a significant role for Japan’s high average life expectancy.

Vitmain K2 is absorbed 100% from the intestines and stays in the blood for several days. The depots in the body is quickly drained if K2 is not sufficiently supplied through the diet, however there is a vitamin K cycle in the body, which contributes to recirculate the vitamin. This cycle is inhibited by the anticoagulation (“blood thinning”) medicine warfarin (Marevan R).

How Does Vitamin K2 Work?

Vitamin K2 is necessary for the blood’s coagulation. It happens with the help of several activating enzyme reactions, which also can bind calcium. K2 has proven to be beneficial with, amongst other things, several forms of severe menstrual bleeding.

The Skeleton

K2’s function in the skeleton happens with the help of the following enzymes: osteocalcin, Matrix Gla protein, Protein S and Gas6.

Osteocalcin is formed in bone-forming cells, osteoblasts, and is necessary for their function. The protein is regulated by vitamin D3. Osteocalcin can also be found in the brain. If there is not enough osteocalcin in the brain, the brain cells become more exposed to the effects of calcium.

An enzyme reaction named gamma-carboxylation is necessary for the mineral binding, the mineralization of the skeleton. Too little carboxylation, under carboxylation, increases the risk of osteoporosis and bone fractures. Vitamin K2 and D3 counteracts under carboxylation of osteocalcin (ucOC). Matrix Gla protein (MGP) promotes growth and development of bone tissue. MHP also prevents the deposition of calcium in soft tissues (such as arteries with arteriosclerosis) and cartilage (osteoarthritis).

Protein S is an antioxidant, which is formed in osteoblasts, the cells from which bone develops). Their role in the bone tissue is not quite understood, however children with a genetic deficiency have a tendency to develop blood clots and reduced bone density.

K2 is dependent on Gas6. It affects the regulation of cell growth and development, and the cells ability to stick together (adhesion) and consequently to prevent spread of cancer.

Gas6 also affects the cells’ ability to commit suicide (apoptosis). In addition the protein plays a role in the development of the nervous system and for the aging nervous system (Nutr Rev 1999. Aug;57(8) : 231-40). It also regulates platelet signals and blood vessel health.

Vitamin K2 is absorbed quickly and effective (100%) and has a long half-life in comparison to K1, which disappears within one and a half hour. The liver, with help of LDL and HDl-cholesterol, redistributes K2 to the bone tissue, blood vessels and other tissue. K2 is reduced by carboxylation to much greater extent than K1.

Vitamin K2 Deficiency

K2 deficiency can be found amongst infants, for whom it causes an increased risk of brain haemorrhage during the birth. It is therefore important that the mother consume vitamin K2 and K1 during the pregnancy. There is only a small amount of vitamin K in breast milk.

Hunger and fasting for several days can lead to a lack of K2, as it is only deposited for a few days. Lack of pro-bacteria (healthy intestinal microflora), caused by for example treatment with antibiotics, reduces the intestinal bacteria’s production of vitamin K. A modern lifestyle with an unhealthy diet can also lead to a lack of vitamin K. It can also happen if one abuses for example alcohol and when taking pharmaceuticals, as for example magnyl, over longer periods of time.

The importance of vitamin K in the prevention of bone fractures is enlightened in studies such as Nurses Health Study, which showed that people who have a low consumption of vitamin K1 had a 30% higher chance of fracturing a bone. However, in the Framingham study no connection was found between K1 from the diet and bone density (BMD), bone strength and risk of bone fractures. On the other hand, it is proved in scientific studies that vitamin K2 reduces the risk of bone loss and fractures. Especially when taken in combination with calcium and vitamin D3. There are few incidences of osteoporosis in Japan, where they ingest sufficiently with K2 through their Natto-dish. Vitamin K2 prevents also kidney stones by normalizing the calcium metabolism. Studies on rats detected a high concentration of vitamin K in the pancreas, and the vitamin seems to play an important role controlling blood sugar. (Int J Vitam Nutr Res, 1999 Jan; 69(1): 27-31).

A Powerful Antioxidant

Vitamin K2 is a powerful antioxidant and counteracts inflammation, which includes inflammations and inflammation-like changes in the body such as rheumatic pains. Inflammations are the reason for, or partly the reason for, pains and several different diseases including atherosclerosis and cancer.

Natto. This traditional Japanese breakfast is made of fermented soybeans and is naturally rich with vitamin K2. However, before you start running to the nearest health food store, you should know that Natto has a slimy consistency and a distinctive, strong odor, which supposedly makes us non-Japanese people turn our backs on it.

Heart and Vessels

Vitamin K2 is far more effective than vitamin K1 whit regards to reducing the risk of cardiovascular diseases. Amongst other studies, the famous Rotterdam study showed that the risk of death caused by blood clots is halved when consuming vitamin K2. Matrix Gla Protein (MGP) is the protein that to the greatest extent prevents atherosclerosis of soft tissue and this protein is dependent on vitamin K2. It protects especially the elastic fibres in the blood vessels against calcification. When the elasticity of the blood vessels is reduced, the risk of high blood pressure increases. Vitamin K2 can even reduce already formed calcification in the blood vessels. It is also proven that a supplement of vitamin E in the form of tocotrienol and garlic can have the same effect. Many modern people have magnesium deficiency, which will prevent uptake of calcium. Vitamin K2 is necessary to incorporate calcium in the bone tissue and to ensure that it does not end up in the cardiovascular system. This is also true for vitamin D3, which most people have too little of in the blood, especially during the winter.

The Need for Vitamin K2

Recommended daily dose of vitamin K2 is normally 90 micrograms for women and 120 micrograms for men. No side effects are detected when consuming vitamin K1 or K2 in as large doses as 135 milligrams daily (in other words, 1000 times as much as the recommended dose).

The blood thinning pharmaceutical Warfarin (Marevan), which is also used in rat poison, prevents recycling of vitamin K (the vitamin K cycle). Warfarin increases the risk of atherosclerosis and creates a significant risk of bleeding. It is therefore necessary with a regular intake of vitamin K1 thought the diet and to take 90-120 micro grams vitamin K2 supplement daily. In that way you do not increase the risk of blood clots and makes it easier to control the treatment. There are effective, natural alternatives for prevention of blood clots, for example fatty fish, vitamin E, garlic and ginger.

Artificial Vitamin K3

Large does of the synthetic vitamin K3 can cause haemolysis (the blood’s red blood cells break down) and anaemia amongst infants. Amongst adults, large doses of vitamin K3 can damage the liver cells and cause allergic reactions. Therefore, one should not take vitamin K3, only the natural vitamins.

Only 5-10% of vitamin K1, from foods such as eggs, green vegetables and carrots, is taken up in the blood and is converted to vitamin K2 in the liver. Vitamin K2 is necessary for, amongst other things, strong bones.

The Doctor

Carsten Vagn-Hansen is from Denmark, has been practising medicine for 18 years and is a lecturer and tutor at Practicing Doctors Centralized Postgraduate Education. He was the president of the International Society for General Practise. He has also received several awards, including The International Nature Medicine Honorary Price. He is the author of numerous books within health and fitness. To top it off, he has been a radio doctor at Danish radio and a TV doctor in DR TV.


Read more at his website RADIODOKTOREN.DK