Why You Need Vitamin K For Your Brain

Evidence is emerging that this is an important anti-dementia nutrient

Vitamin K is not the first nutrient that springs to mind when you think about strengthening your natural reserves against dementia. There are plenty of others, many of which have been well documented here and elsewhere. But that is to ignore the full potential of this old workhorse of a vitamin, ploughing away in the background to little critical acclaim.

That vitamin K keeps your bones and your heart strong is well established. But less well known, but beginning to emerge, is the evidence that it can also help ward off cognitive impairment and even dementia in later life.

There are two main forms of this fat-soluble vitamin: vitamin K1 (phylloquinone) and K2 (menaquinone). When you read about requirements for vitamin K, you are almost certainly reading about vitamin K1, which is best known for its role in blood clotting.

VK1 is probably better known because it is found a lot more abundantly in the diet than VK2. VK1 is the one found in dark leafy greens such as spinach and kale, and is routinely given to newborn babies, in case of bleeding.

VK2 is much more complex. There are 10 subgroups of VK2, ranging from MK-4 to MK-13. In bones, it activates the protein osteocalcin which binds to calcium, therefore helping to lower the risk of developing osteoporosis.

The richest known source of VK2 is natto, a Japanese speciality made from fermented soya beans. The problem we have in the West is that the diet is typically low in VK2. On average, VK2 comprises just 10% of all vitamin K consumed in Europe.

Fermentation is the key word: The menaquinones are made predominantly by the fermentation of bacteria in the gut. However, they are also found in moderate amounts  in animal-based foods.