Getting enough of certain vitamins has been linked to better health outcomes – adequate vitamin D consumption and fish oil supplementation, for example, could lower our risk of dementia; while a daily multivitamin could slow biological (cell-level) ageing, too.
But not every nutrient that could benefit us over time is equally well-known.
Choline, an “underconsumed and underappreciated” substance found in foods like egg yolks, can contribute to better brain function in menopause, for instance.
And it turns out that a deficiency in another less-discussed vitamin may “cause age-related diseases such as cardiovascular diseases, neurodegenerative diseases and osteoporosis”, according to a 2024 paper.
Vitamin K: sources, dosage, and how it helps with better ageing
What is vitamin K and why is it good for ageing?
Vitamin K is a fat-soluble family of vitamins that is mostly associated with helping your blood to clot better. (In fact, newborn babies, who are typically born with low levels of the vitamin, are usually given an injection of it at birth to prevent internal bleeding.)
But, as a 2019 paper pointed out, that might undersell the nutrient. “It is currently known that the range of vitamin K action is far beyond the scope of blood coagulation,” it reads.
The study added that vitamin K offers “novel and less explored functions as [a] molecule with anti-inflammatory and antioxidant properties,” which may be beneficial for our heart and bones as we get older.
Separate research found that calcium-balancing vitamin K appeared to preserve bone density and strength at weight-bearing parts of the hip for post-menopausal women.
Vitamin K could also keep your brain healthy and help to protect against dementia by activating a brain protein called Gas6. This, in turn, can shield our brain cells. It may improve how we metabolise glucose, as well – important, seeing as our glucose tolerance gets lower the older we become.
Vitamin K2, more specifically, was named as a “neglected player in cardiovascular health” in one narrative review. It could reduce our risk of developing stiff and/or calcified veins and arteries, both of which become more likely in later life.
Some of the papers we looked at mentioned how little research there was into vitamin K and health in older age, however.
One study about vitamin K and cognitive health mentioned a “paucity of published papers” on the topic, while another said “most of the available studies are observational and only a few randomised trials are currently available”.
How much vitamin K do I need?
We don’t know what will happen if you take too much vitamin K, but the NHS says we should aim daily for one microgram of vitamin K per kilogram of body weight. It added that taking 1mg or less of vitamin K supplements a day “is unlikely to cause any harm”.
However, the health service added that most of us should be able to get enough vitamin K through a balanced diet.
Bailey Heedick via Unsplash
What are some sources of vitamin K?
Good sources of vitamin K include:
- Green leafy vegetables like broccoli and spinach,
- Vegetable oils, like soybean oil, canola oil, or olive oil,
- Nuts like roasted cashews or pine nuts,
- Cereal grains,
- Some juices, like carrot juice and pomegranate juice,
- Some meat and dairy foods, though not much.
Because vitamin K is a fat-soluble vitamin, it’s best consumed with healthy fats – like those found in avocados or nut butters – to help your body absorb it better.
I’m off to rustle up a salad…
