Cognitive decline is a natural part of aging, but several lifestyle factors and dietary components can affect brain health.
Vitamin K, a group of fat-soluble vitamins essential for blood clotting and bone metabolism, has also been linked to brain function and cognitive performance. Recent research shows that vitamin K protects the brain from cognitive decline and can potentially prevent or delay the onset of dementia.
What is Vitamin K?
Vitamin K is a group of fat-soluble vitamins that play a crucial role in blood clotting, bone metabolism, and cardiovascular health.
There are two main forms of vitamin K: vitamin K1, or phylloquinone, found in green leafy vegetables, and vitamin K2, or menaquinone, found in fermented foods and animal products. Vitamin K2 is further divided into subtypes, such as MK-4 and MK-7, which have different biological activities and distribution in the body.
Vitamin K and Brain Function
Although vitamin K’s primary function is in blood clotting and bone metabolism, recent research has linked it to brain health and cognitive function.
Vitamin K is involved in the synthesis of sphingolipids, a type of cell membrane component necessary for neuronal growth and function. Vitamin K also activates a protein called Gas6, which regulates the survival and growth of neurons and glial cells in the brain.
Studies have found that vitamin K deficiency is associated with poorer cognition, memory, and executive function, as well as a higher risk of Alzheimer’s disease and other forms of dementia.
Research Studies
A study published in 2016 in the Journal of Gerontology: Medical Sciences investigated the association between vitamin K intake and cognitive performance in older adults.
The study included 320 men and women aged 70-85 years and measured their dietary intake of vitamin K1 and K2 using food frequency questionnaires. The researchers found that higher vitamin K1 and K2 intake was significantly associated with better cognitive performance, particularly in memory and executive function tasks.
The results suggest that vitamin K has a protective effect on brain health and may help prevent cognitive decline in older adults.
Related Article
Study Finds Vitamin K to Be Key for Brain Functioning
Another study published in 2020 in the Journal of Alzheimer’s Disease examined the relationship between vitamin K levels and the risk of dementia in a cohort of older adults.
The study included 370 participants aged 65 years or older without dementia at baseline and followed them for up to 14 years. The researchers measured the participants’ plasma levels of vitamin K1 and K2 at baseline and found that higher vitamin K levels were associated with a lower risk of dementia.
The association was stronger for vitamin K2 than K1 and persisted after adjusting for other risk factors, such as age, sex, education, and lifestyle. The findings indicate that vitamin K may have a preventive role in dementia and should be included in dietary recommendations for brain health.
Dietary Sources of Vitamin K
Vitamin K is found in a variety of foods, including leafy greens, cruciferous vegetables, herbs, spices, and animal products.
The following table lists some of the best sources of vitamin K, their vitamin K content per serving, and the recommended daily intake for adults.
| Food Source | Vitamin K Content (mcg/serving) | Recommended Daily Intake (mcg) |
|---|---|---|
| Kale (1 cup raw) | 547 | 90-120 |
| Spinach (1 cup cooked) | 888 | 90-120 |
| Broccoli (1 cup chopped) | 220 | 90-120 |
| Brussels sprouts (1 cup cooked) | 219 | 90-120 |
| Parsley (1/2 cup chopped) | 492 | N/A |
| Beef liver (3 oz cooked) | 10 | N/A |
| Chicken breast (3 oz cooked) | 0.1 | N/A |
| Egg yolk (1 large) | 0.1 | N/A |
Vitamin K Supplements
Vitamin K supplements are available in various forms, including capsules, tablets, and drops. Vitamin K1 and K2 supplements are also sold separately or in combination with other vitamins and minerals, such as vitamin D and calcium.
However, taking high doses of vitamin K supplements can interfere with certain medications, such as blood thinners, and lead to adverse effects, such as bleeding and liver damage. Therefore, it is essential to consult with a healthcare provider before taking any vitamin K supplements, especially if you are taking medication or have a medical condition.
Conclusion
Vitamin K is a vital nutrient for maintaining bone health and blood clotting, but it also plays a significant role in brain function and cognitive performance.
Research shows that higher vitamin K intake and plasma levels are associated with better memory, executive function, and a lower risk of dementia in older adults. Vitamin K is found in a variety of foods, especially leafy greens and animal products, and can also be obtained through supplements.
However, caution should be taken when taking high doses of vitamin K supplements, especially in combination with other medications or medical conditions.
