Vitamins D and K are usually obtained with plenty of high fat foods. For example, it is abundant in fatty fish and fish oil, but it is also produced by the skin when exposed to sunlight.
The main function of vitamin D is to promote the absorption of calcium and maintain adequate levels of it in the blood. In contrast, a deficiency of these can cause bone loss.
For its part, vitamin K is found in green leafy vegetables and legumes, as well as in some foods of animal origin, such as egg yolk , liver and cheese. It is necessary for the coagulation of the blood and promotes the accumulation of calcium in bones and teeth.
Therefore, getting adequate amounts of vitamin D and K is essential for health. However, some sources claim that vitamin D supplements is harmful if it has low vitamin K content.
Find out what the science says about this claim.
Aspects to know about vitamins D and K
1.Why is it important to consume vitamins D and K together?
Both vitamins are vital for calcium metabolism. The role that each one plays consists of the following:
1.1 Vitamin D
One of the main functions of vitamin D is to maintain adequate levels of calcium in the blood; and there are two ways in which you can achieve it:
- Through the food that is consumed.
- By taking calcium from bones when not enough of it is consumed; In this way vitamin D maintains its blood levels by acquiring it from the bones.
Although calcium is best known for its role in bone health, maintaining your blood levels is very important because it has many other vital functions in the body.
Vitamin D and its relationship with vitamin K
1.2 Vitamin K
Despite the important performance of vitamin D , it does not completely regulate calcium in the body. Hence the necessary participation of vitamin K. This vitamin regulates calcium in your body in 2 ways:
- Promoting the calcification of bones; specifically by activating osteocalcin , a protein that promotes the accumulation of calcium in bones and teeth.
- Reducing the soft tissue calcification. Vitamin K activates a protein that prevents calcium from accumulating in soft tissues, such as the kidneys and blood vessels. However, it seems that the calcification of the blood vessels is related to the development of chronic diseases, such as those related to the heart and the kidney. However, on the veracity of these facts there are still studies in process.
2.Is vitamin D harmful without vitamin K?
Some people worry that a high intake of vitamin D and low vitamin K may cause calcification of blood vessels and heart disease.
In this sense, some scientific evidence establishes the following:
- The vitamin D causes hypercalcemia: one of the symptoms of vitamin D levels extremely high, resulting in very high levels of calcium in the blood.
- Hypercalcemia leads to calcification of blood vessels. The levels of calcium and phosphorus become so high that calcium phosphate begins to accumulate in the blood vessels.
- The calcification of blood vessels is associated with heart disease.
In this regard, studies say that vitamin K deficiency is associated with calcification of blood vessels. In addition, a study in rats showed that vitamin K supplements in high doses in animals prevented calcification. For its part, another study in humans showed that supplements with 500 mcg of vitamin K1 every day for 3 years reduced this effect by 6%.
In short, an excessive intake of vitamin D can cause calcification of blood vessels, while vitamin K can help prevent this from happening. However, until now there is no evidence to show that moderate amounts of vitamin D are harmful without adequate vitamin K intake.
3.How is vitamin K presented?
The Vitamin K comes in many different forms, traditionally divided into two groups:
- Vitamin K1 ( phylloquinone ). It is the most common form of vitamin K and is found in plants, especially green leafy vegetables such as kale and spinach.
- Vitamin K2 ( menaquinone ). It is much rarer in food and is found mainly in those of animal origin and in fermented foods.
- MK-4 (menaquinone-4 ). It is found in foods of animal origin such as liver, egg yolk and cheese.
- MK-7 (menaquinone-7 ). Formed by bacterial fermentation. It is found in foods such as natto and miso.
4.What is the adequate intake of vitamin K?
Current dietary recommendations do not distinguish between vitamin K1 and K2. For people over 19 years of age, adequate intake is 90 mcg in women and 120 mcg in men.
The exclusion of foods with vitamin K in your daily diet could help you to reach the minimum requirements of this. Supplements are also widely available.
In addition, since vitamin K is soluble in fat, consuming it with fat can improve its absorption. For example, you can add a little oil to leafy foods or take the supplements accompanied by a meal containing fat.
It is clear that vitamin K benefits the heart and bones, but it remains to be confirmed if supplements of high doses of vitamin D are harmful when your body has little vitamin K.
However, it is important that you make sure you get adequate amounts of both vitamin D and K through your diet, because both are important.
Finally, it is not recommended to take very high doses of vitamin K supplements without first talking to a doctor, as it may interact with certain medications.