What is vitamin K?
Vitamin K refers to a group of fat-soluble vitamins, with the two primary forms being vitamin K1 and vitamin K2. Vitamin K is responsible for blood clotting. This may sound like a bad thing, but without vitamin K we would bleed out excessively, even from a small cut. Vitamin K also plays a role in bone and heart health.
In terms of bone health, vitamin K helps to activate the protein required for bone growth and development. This can be beneficial for young children or for those with osteoporosis. Studies have shown a decrease in fracture rates, specifically of hip fractures.
Vitamin K also has a positive effect on heart health, as it can prevent calcium from depositing plaque in the arteries. Reducing the build-up of plaque is associated with a lower risk of heart disease.
Vitamin K1 is generally found in green leafy vegetables, like kale, spinach, broccoli and brussels sprouts. It makes up approximately 75-90% of the vitamin K consumed by humans; however, it’s poorly absorbed by the body. Vitamin K1 can also convert into vitamin K2, but the conversion process is generally inefficient.
Vitamin K2 has two primary sources. Firstly, it can be found in fermented foods like miso and natto beans, or in grass-fed animal products, like beef, dairy, cheese and eggs. Additionally, small amounts of vitamin K2 can be produced in our gut bacteria. Little is known about vitamin K2’s absorptive capacity. However, because vitamin K2 foods contain higher amounts of fat and are circulating in our blood for an extended period, they are more likely to be better absorbed.
How much vitamin K do we need?
Women need 90 micrograms, whereas men need 120 micrograms of vitamin K each day. Some simple ways to increase our vitamin K intake include:
Consuming these foods with a source of fat (e.g. olive oil) will also help with vitamin K absorption. Alternatively, vitamin K supplements are available, which can be beneficial for people with osteoporosis. Vitamin K supplements can be used in conjunction with calcium and vitamin D to support bone strength and reduce the risk of fractures.
What if I take a blood thinner?
Some people are required to take a blood thinner to reduce the risk of blood clot formation. Warfarin is a common medication used to thin the blood. Research has shown that when taking blood thinners, it’s essential to have consistent amounts of vitamin K.
Overall, we must incorporate vitamin K-rich foods into our diet. This includes foods from both vitamin K1 and vitamin K2, which will support optimal blood clotting. Those who are taking a blood thinner are also advised to consume consistent amounts of vitamin K each day. If you have any questions regarding vitamin K, give us a call at CQ Nutrition to speak with one of our dietitians.
Written by Annabel Johnston, BAppSc&MDietPrac