As we age, our bodies change in ways that increase the odds of developing health problems, including cardiovascular disease, type 2 diabetes, and degenerative diseases such as osteoarthritis and dementia. Good nutrition is one approach to lowering the risk of chronic health issues and even slowing the aging process itself. Studies show diets high in total fat, saturated fat, and salt, and low in fiber, fruits, and vegetables contribute to cardiovascular disease, type 2 diabetes, and cognitive decline in the elderly.
But there’s some evidence that deficiency in vitamin K, a nutrient crucial for maintaining healthy blood vessels, may contribute to aging and age-related diseases. According to a recent multiethnic study led by researchers at Tufts University, older adults with low vitamin K levels were at a higher risk of dying within 13 years than those with adequate quantities of this essential nutrient.
Vitamin K1 and Vitamin K2: Sources and Functions
Vitamin K is a vitamin you hear less about than other common vitamins, like vitamin C but that shouldn’t underscore its importance. Vitamin K is a fat-soluble nutrient that plays a vital role in blood coagulation, bone health, and cardiovascular health. It comes in two forms: Vitamin K1, in green leafy vegetables and other plant sources, and K2, created by gut bacteria and found in some foods.
Vitamin K2 is abundant in meat and dairy from grass-fed animals. Along with butter and cheese made from grass-fed cow’s milk, grass-fed meat, fowl, and eggs also contain this vitamin. A fermented soy food called natto is one of the best non-animal sources of vitamin K2. Natto is a traditional Japanese dish consisting of fermented soybeans with many nutritional benefits.
Vitamin K2 has a distinct role in health. While vitamin K1 is involved in blood clotting, preliminary research finds that vitamin K2 helps support healthy bones and blood vessels. It serves as a cofactor for processes that support bone and heart health. One theory is that it helps direct calcium toward bone tissue and away from the inner walls of arteries, where it could be harmful.
Gut bacteria can convert some of the vitamin K1 you consume through diet to vitamin K2, the amount is small and varies from person to person, depending on their gut microbiome. So, it’s best to get vitamin K2 directly from food or supplements.
Despite the rarity of vitamin K insufficiency, many people still don’t get enough of it in their diet. In addition, consuming too much vitamin K might interfere with blood thinners like warfarin, so you may need to limit vitamin K-rich foods if you’re taking this type of medication. Before making any big dietary changes or starting a supplement, speak with your doctor.
Vitamin K and Mortality: Findings from a Multiethnic Study
Let’s delve more deeply into the research. The study involved nearly 4,000 Americans between 54 and 76, including one-third who were non-white. The researchers measured the participants’ vitamin K levels and followed them for 13 years to track their health outcomes.
They conducted a meta-analysis (a review of multiple studies) to combine data from three continuing studies, namely the Health, Aging, and Body Composition Study, the Multi-Ethnic Study of Atherosclerosis, and the Framingham Heart Study (Offspring Cohort). The number of heart disease occurrences was lower compared to the total number of fatalities, possibly interfering with the researchers’ ability to identify a statistically significant risk of heart disease from getting inadequate K2.
Still, the results were enlightening. Those with the lowest vitamin K levels had a 19% higher risk of death than those with adequate levels of the nutrient. This is a significant finding that highlights the importance of getting enough vitamin K.
Based on this study if you want to reduce your mortality risk. Include vitamin K-rich foods, such as leafy greens, cruciferous vegetables, sources of vitamin K1, and grass-fed meat and dairy, K2 sources, to your meals. Interestingly, the study found no significant associations between vitamin K levels and heart disease, but it’s helpful to know that vitamin K may still have benefits for lowering mortality.
One limitation of the study is that participants taking the blood thinner warfarin were excluded because vitamin K counteracts the anticlotting effects of warfarin. Nevertheless, the study highlights the importance of maintaining adequate vitamin K levels through diet.
Getting Sufficient Vitamin K: Food Sources and Supplementation
Along with leafy greens like lettuce, kale, and spinach, vitamin K (in the form of vitamin K1) is in other plant-based foods, including broccoli, Brussels sprouts, and even some fruits like Kiwi and grapes. If you’re looking for a quick and easy way to add more vitamin K to your diet, reach for a salad topped with colorful vegetables and a splash of olive oil or some roasted Brussels sprouts as a side dish.
Leafy greens and other vegetables aren’t a significant source of vitamin K2. To get vitamin K2, you can enjoy creamy Gouda and aged blue cheese or experience the unique taste of natto, a fermented soy food that’s one of the best non-animal sources of vitamin K2. Other sources include grass-fed beef, chicken breast, egg yolks, and sauerkraut.
Conclusion: The Importance of Maintaining Optimal Vitamin K Levels
The Tufts University study shows that older adults with low vitamin K levels may be at a higher risk of dying within 13 years. Further research is needed to fully comprehend the relationship between vitamin K intake and its impact on health outcomes. Still, maintaining proper levels of vitamin K is essential for health.
This study is a crucial reminder that with age, you should be more vigilant about nutrient intake to maintain optimal health and well-being. Eat a balanced diet emphasizing whole, nutrient-dense foods and skip the junk. It’s one of the smartest things you can do for health and healthy aging.
References:
- News (2023). Available at: https://www.todaysdietitian.com/news/081420_news.shtml (Accessed: 4 May 2023).
- Riphagen IJ, Keyzer CA, Drummen NEA, de Borst MH, Beulens JWJ, Gansevoort RT, Geleijnse JM, Muskiet FAJ, Navis G, Visser ST, Vermeer C, Kema IP, Bakker SJL. Prevalence and Effects of Functional Vitamin K Insufficiency: The PREVEND Study. Nutrients. 2017 Dec 8;9(12):1334. doi: 10.3390/nu9121334. PMID: 29292751; PMCID: PMC5748784.
- Denny A. An overview of the role of diet during the ageing process. Br J Community Nurs. 2008 Feb;13(2):58-67. doi: 10.12968/bjcn.2008.13.2.28157. PMID: 18414240.
- “Vitamin K2: Everything You Need to Know – Healthline.” https://www.healthline.com/nutrition/vitamin-k2.
- “Vitamin K – Health Professional Fact Sheet.” https://ods.od.nih.gov/factsheets/vitaminK-HealthProfessional/.
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