Vitamin K deficiency alters health and memory of the brain

Understanding how nutrients affect the brain is an increasing objective in research on aging and a new study has highlighted vitamin K.

Directed by a team from Jean Mayer Usda Human Nutrition Research Center on Aging (HNRCA) at TUFTS University, the recent survey, published in The Journal of Nutritionhas provided new information on how vitamin K can influence brain health. They found that a diet poor in vitamin K led to alteration in memory performance, reduces the formation of new neurons in the hippocampus and signs of increased brain inflammation.

Cognitive nutrition and aging

Age -related cognitive decline affects millions in the world and, as life expectancy continues to increase worldwide, understanding how to support brain health in old age has become an increasingly urgent field of research. While genetic and lifestyle factors play a role, it is more and more recognized that nutrition contributes to shaping cognitive trajectories.

Recent research has been abundant on specific nutrients that can influence cerebral function, including omega-3 fatty acids, B vitamins, antioxidants and, more recently, vitamin K. Known mainly for its role in blood clotting, vitamin K is essential for clinical nutrition. However, evidence is reviewing that it can also contribute to cardiovascular health, bone metabolism and neurological function.

Vitamin K exists in two main forms:

• Phylloquinone (vitamin K₁): found mainly in green leafy vegetables such as spinach, kale, green cabbage, broccoli and Brussels cabbage.
• Menaquinons (vitamin K₂): a group of compounds found in animal products and fermented foods and produced in small quantities by intestinal bacteria.

In the United States, the adequate contribution recommended for vitamin K₁ is 120 μg per day for adult men and 90 μg per day for adult women, According to the National Institutes of Health. Despite these recommendations, the data suggest that many elderly people do not meet the daily requirements of vitamin K.

“There are research that indicates that vitamin K contributes to brain function and that brain function decreases during the aging process,” said the main author, Dr. Tong Zheng, researcher at Jean Mayer USDA HNRCA at TUFTS University.

Observation studies have linked higher vitamin K with better cognitive results in the elderly. Data from the memory and aging project have shown that individuals with higher vitamin K concentrations in their brain had lower levels of dementia, including fewer neurofibrillary.

While the food models rich in vitamin K seem beneficial, the biological mechanisms behind the effects of vitamin K on the brain are still not well understood.

Vitamin K deficiency alters memory and growth of brain cells

Zheng and his colleagues designed a 6 -month food intervention using 60 C57bl / 6 mouse of average age. The mice have been divided into two groups: one received a standard diet containing adequate levels of vitamin K, while the other group was fueled by a vitamin K deficient diet containing that a fraction of the recommended quantity. The control diet provided 1 mg / kg of phylloquinone, while the deficient vitamin K diet contained only 80 μg / kg – a reduction of more than 90%. The study was specifically on Ménaquinone-4 (MK-4), the most widespread vitamin K form in cerebral tissues.

After six months, mice underwent a series of behavioral tests to assess learning and memory. In the new object recognition test, which measures recognition memory by assessing how long the mice spent exploring a new familiar object, the vitamin K group has shown clear deficiencies. These mice spent much less time with the new object, which indicates a reduced capacity to distinguish new stimuli and familiar stimuli – a characteristic of the decline of memory.

In a second test – the Morris water labyrinth, which assesses spatial learning and memory – mice deficient in vitamin K have also underperform. During several tests, they took more time to locate a hidden platform in a water swimming pool, suggesting learning and conservation of spatial information compared to their imprecise counterparts.

Beyond behavioral changes, the study revealed differences in the structure and function of the brain. When the researchers analyzed the hippocampal tissues, a region of the brain essential to learning and memory, they found that mice deficient in vitamin K had a reduction in the levels of MK-4 and considerably reduced neurogenesis in their brain tissue. These mice have shown fewer proliferating cells and immature neurons in the toothed gyrus, a hippocampal sub-region where new neurons are even born in adulthood.

“We think that neurogenesis plays an essential role in learning and memory, its impairment could contribute directly to the cognitive decline observed in the study”, ” said Zheng.

The team also identified signs of increasing neuroinflammation in the deficient group. A higher number of activated microglies – resident brain immune cells – have been observed in the vitamin K -deficient group. While the total number of microglies has remained similar between groups, vitamin K deficient mice showed simpler and less branched structures – an indicator of a more activated and potentially inflammatory state. Excessive microglial activation is associated with chronic inflammation and has been involved in neurodegenerative diseases.

Males mice in the vitamin K deficient diet have experienced significantly lower survival rates and less weight gain during the study period compared to female mice and control males. The researchers found no proof of bleeding in mice deficient in vitamin K who are dead, which suggests that the mortality observed can be linked to other physiological effects of the deficiency.

Complete vitamin K is not necessary

This research strengthens the idea that vitamin K can have a role in supporting brain health, especially in the context of aging. Although the study was conducted in mice, it aligns with the results of human observation studies which combine a higher supply of foods rich in vitamin K with better cognitive results in the elderly.

One of the mechanisms highlighted in this study is the potential for vitamin K to help maintain neurogenesis to regulate neuroinflammation.

“Vitamin K seems to have a protective effect,” said Zheng. “Our research is trying to understand the underlying mechanism of this effect so that we can one day target these mechanisms specifically.”

In the meantime, researchers aim to validate these mechanisms in human studies, to study how vitamin K interacts with other food components and aging processes and explore if its role in neuroinflammation and cellular development could clarify future therapeutic strategies.

“We know that a healthy diet works and that people who do not eat a healthy diet do not live so long or do not so well.

Although the team highlights the objective of their research on the realization of adequate vitamin K through food sources, not supplementation.

“People need to eat a healthy diet. They need to eat their vegetables, ”said Booth.

Reference: Zoms T, Mars Crschal S, We Soveberg J, it’s old. Low consumption of vitamin K alters cognition, neurogenesis and raises neuroinflammation in mice C57BL / 6. Nose. 2025: S0022316625000306. DOI: 10.1016 / J.TJNUT.2025.01.023

This article is a resumption of a press release Issued by TUFTS University. The material has been modified for duration and content.