Vitamin K
In this blog post, we will evaluate another fat-soluble vitamin –Vitamin K. We will identify its types, sources, and functions.
There are 3 types of Vitamin K comprising :
Natural forms
- Vitamin K1 (phylloquinone) – obtained from plants.
- VitaminK2(menaquinone)- contained in certain animal sources and fermented products.
Synthetic Form
- Vitamin K3 (menadione or menaphthone)-the synthetic form of Vitamin K.
Functions of Vitamin K
- Blood clotting– Prothrombin ( a vitamin K-dependent protein) contributes an essential role in blood clotting.
- Healing of wounds-Vitamin K promotes the fast healing of wounds.
- Bone metabolism-Vitamin K is integral in maintaining bone health. It works alongside Vitamin D to promote calcium metabolism, which is essential for a healthy skeletal structure and enhanced bone density.
Sources Of Vitamin K
Vitamin K1 sources include:
- Dark green leafy vegetables –kales, lettuce, spinach, broccoli, asparagus
- Vegetable oils –soybean oil, canola oil
Vitamin K2 sources include:
- Eggs
- Meat
- Dairy products
RDA
- Men (>19 years) -120 micrograms
- Women (>19 years) 90 micrograms
Individuals at Risk of Vitamin K deficiency
- Individuals with health conditions that hinder fat absorption-Conditions such as liver damage and Chron’s disease that interfere with fat absorption, negatively impact an individual’s Vitamin K status. These conditions decrease the vitamin’s absorption and utilization.
- Infants – At birth, their vitamin K body stores are insufficient. They also only receive insignificant amounts of Vitamin K from their mothers through the placenta. They lack the bacteria necessary for vitamin K synthesis in their intestines.
Vitamin K Deficiency
Vitamin K deficiency is rare although infants are most susceptible to it.Infants with Vitamin K deficits may have haemorrhagic disease. Other individuals with the deficiency may easily bruise or bleed.
Vitamin K Toxicity
Natural Vitamin K sources present no toxic effects. Nonetheless, its synthetic form (menadione) is likely to not only cause liver damage but also neonatal haemolysis due to its high reactivity. Vitamin K supplements when taken in excessive amounts can counter the effects of anti-coagulants and antibiotics targeting the prevention of blood coagulation.
Note that taking any form of supplement predisposes one to toxicity. It is best that you obtain your Vitamin K from its food sources rather than supplements. In case of conditions or medications that interfere with its availability, it is integral that you seek advice from a professional dietitian.
Nutrient Interactions With Vitamin K
- Vitamin E –High amounts of Vitamin E impede Vitamin K absorption as it interferes with its coagulation abilities.
- Vitamin A –In excess amounts, it hinders the absorption of Vitamin K.
- Vitamin D-Both Vitamin K and Vitamin D play a crucial role in calcium metabolism.
- Calcium -Vitamin K regulates calcium in your body by activating osteocalcin(a protein necessary for bone metabolism).
Drug Interactions With Vitamin K
- Cholesterol-lowering medications –Similar to other fat-soluble vitamins, Vitamin K’s absorption is interfered with cholesterol-lowering medications that hinder fat absorption. Since dietary fat is necessary for absorbing vitamin K, individuals under the prescription of these medications have an increased risk of deficiency.
- Anticonvulsants such as phenytoin-These drugs are likely to enhance the risk of deficiency among foetuses or infants, especially when consumed during the pregnancy or breastfeeding periods.
- Blood thinners, such as warfarin –These medications work against the formation of clots and hence are counteractive towards Vitamin K blood clotting functions. Thus, they may interfere with vitamin K’s clotting ability depending on whether the vitamin’s intake is greatly increased or greatly reduced.
Vitamin K intake is essential. It offers a variety of functions, most especially the preservation of bone health and blood clotting abilities. You should ensure that you integrate nutritious food sources of Vitamin K in your diet to meet the recommended intake.