Written by Jessica Patella, ND. Vitamin K was associated with an 8.2% improvement in verbal memory recall.
Vitamin K is a fat-soluble vitamin found primarily in green leafy vegetables (1). Vitamin K is mostly known for being important in the clotting process, but recent research has suggested vitamin K may play a role in memory, especially during aging (1). Up to this point, research has only been conducted in rodents, which shows mice eating vitamin K enriched diets perform better and learn faster (1,2). Now, the first study in humans shows there is an association between vitamin K levels in the body and memory in healthy older adults (1).
The research included 320 participants from 70-85 years of age who were in general good heath, able to perform normal daily activities and did not have cognitive or memory impairment, based on a mini-mental status exam (1).
The participants underwent 6 cognitive tests covering 4 main areas: verbal memory (episodic), non-verbal memory (episodic), decision-making (executive functions) and speed of processing (1). The verbal and non-verbal memory tests were episodic, meaning the memory was of an event that had a time and space context. For example, remembering where you left your keys last is an episodic memory (1). Blood was also drawn to measure vitamin K levels in the body (phylloquinone concentrations) (1).
Higher levels of vitamin K in the blood were associated with better performance on the verbal episodic memory tests (p<0.05). When further analyzing the verbal memory tests, an increase in vitamin K levels in the blood from 0.27 to 1.06 nmol/L (from the 2.5th# to 50th percentile) was associated with an increase of 8.2%, 6.1% and 6.4% in performance on the 2-minute, 3-minute, and 20-minute delayed recall of a verbal episodic memory (1).
There was no association with vitamin K levels in the blood and non-verbal memory (episodic), decision-making (executive functions) and speed of processing (1).
This study is important because it provides support for new findings that vitamin K plays a role in the brain and with memory (1, 2). This especially, raises questions for those treated with vitamin K-antagonists, like the blood thinner warfarin (1).
In conclusion, vitamin K may play a role in verbal memory in the elderly population (1). Further double-blinded studies should be conducted to determine if supplementing with vitamin K could affect memory and to get a better understanding of how vitamin K works in the brain (1).
#2.5 percentile is correct
Source: Presse, Nancy, et al. “Vitamin K status and cognitive function in healthy older adults.” Neurobiology of aging 34.12 (2013): 2777-2783.
© 2013 Elsevier Inc. All rights reserved.
Posted October 15, 2013.
Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health. She earned her ND from Southwest College of Naturopathic Medicine in Tempe, AZ, and is a member of the North Carolina Association of Naturopathic Physicians. Visit her website at www.awarenesswellness.com.
References:
- Presse N, et al. Vitamin K status and cognitive function in healthy older adults. Neurobiology of Aging 32 (2013) 2777-2783.
- Carrie I, et al. Lifelong low-phylloquinone intake is associated with cognitive impairments in old rats. J Nutr 141 (2011) 1495-1501.
