Research Suggests Vitamin K Linked to Heart Health and Longevity

Bowl of spinach

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Key Takeaways

  • A new study suggests vitamin K deficiency may shorten your lifespan.
  • This protective vitamin prevents calcium buildup in artery walls, improving cardiovascular health.
  • Before taking a vitamin K supplement, first try including foods rich in the vitamin, like dark leafy greens and cruciferous vegetables.

Although every vitamin and mineral confers benefits, vitamin K may be a particular standout when it comes to increasing longevity, new research suggests.

A meta-analysis published in The American Journal of Clinical Nutrition looked at research from three major studies, representing over 4,000 participants aged 54 to 76, and found that those with the lowest vitamin K levels had a 19 percent higher risk of death compared to those with adequate intake of the vitamin.

Researchers did acknowledge the study is observational, which means it doesn't prove cause and effect. In other words, it doesn't show that low vitamin K levels are the cause of a shorter life, merely that there's an association.

That said, this connection might happen because vitamin K is crucial for maintaining healthy blood vessels, according to first author Kyla Shea, PhD, a scientist on the Vitamin K Team at the Human Nutrition Research Center on Aging at Tufts University.

There's a protein in vascular tissue that prevents calcium from building up in artery walls, and it requires vitamin K to function, she says. Without vitamin K, this protein is less functional, which may increase susceptibility to calcium accumulation in arterial walls.

When that buildup happens in coronary arteries, it's associated with atherosclerosis and cardiovascular disease, she adds. Calcium buildup in other arteries throughout the body can cause arteries to become stiff, and Shea says that's also been linked to early mortality in past research.

Why Older Adults May Be Vitamin K Deficient

Like any other essential vitamin or mineral, it's important for people of all ages to get the recommended amount of vitamin K—the USDA puts that amount at 90 mcg per day for women and 120 mcg per day for men —but older adults tend to need more.

That's because as we age, there's a decreased ability to sufficiently absorb nutrients from food, according to Samantha Cochrane, RD, dietitian at The Ohio State University Wexner Medical Center.

With vitamin K, that's a concern not just because of cardiovascular health, but also for bone density, she says, since the vitamin affects the way bone is mineralized.

A research review in Nutrition reported that vitamin K can improve calcium balance and bone health, especially when paired with vitamin D. Although many of the studies covered focused on people with osteoporosis, the researchers concluded that increased intake of the vitamin can help bone density for everyone, even at low doses.

Samantha Cochrane, RD

With older adults already at risk for bone fractures and osteoporosis, it is important to get enough of this nutrient, as well as others, that play a role in maintaining bone integrity.

— Samantha Cochrane, RD

Food vs. Supplements

The biggest question people tend to have when they hear about the benefits of a certain vitamin or mineral is: Should I be including this in my supplements?

Although vitamin K is available as a standalone vitamin supplement and is part of many multivitamin blends, Cochrane says a better starting point for boosting your intake is through food—particularly because foods highest in vitamin K are dark leafy greens and cruciferous vegetables. Those are packed with other nutrients, phytochemicals, antioxidants, and fiber that provide even more benefits for your body beyond the inclusion of just vitamin K.

Also, they tend to have high enough amounts of the vitamin to easily meet the recommendations and go beyond them. For example, half a cup of cooked spinach has 469 mcg of vitamin K.

Top Choices for Vitamin K

  • Brussels sprouts
  • Swiss chard
  • Kale
  • Collards
  • Turnip greens
  • Mustard greens
  • Romaine lettuce
  • Cabbage
  • Asparagus
  • Broccoli
  • Beet greens

One important note, Cochrane adds, is that vitamin K is a fat-soluble vitamin, which means you need to eat some fat at the same time for it to absorb efficiently into your body. It doesn't take much, though—a drizzle of olive oil on your salad or in a sauté would be enough.

"There are lots of easy ways to incorporate these daily, whether it's mixing a salad, lightly steaming a side of collard greens, or adding spinach to your eggs in the morning," Cochrane says. "The most important thing when selecting a way to incorporate these foods is to do it in a way you like, so you continue to do it often."

3 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Shea MK, Barger K, Booth SL, et al. Vitamin K status, cardiovascular disease, and all-cause mortality: a participant-level meta-analysis of 3 US cohortsAm J Clin Nutr. 2020;111(6):1170-1177. doi:10.1093/ajcn/nqaa082

  2. MedlinePlus. Vitamin K.

  3. Weber P. Vitamin K and bone health [published correction appears in Nutrition 2001 Nov-Dec;17(11-12):1024]Nutrition. 2001;17(10):880-887. doi:10.1016/s0899-9007(01)00709-2

By Elizabeth Millard, CPT, RYT
Elizabeth Millard is a freelance journalist specializing in health, wellness, fitness, and nutrition.