Vitamin K may offer protective health benefits in older age

In the journals

Vitamin K is an often ignored nutrient, but new research has found that low levels among older adults may increase their risk of early death. The findings were published in the June 2020 issue of The American Journal of Clinical Nutrition.

Researchers looked at about 4,000 adults ages 54 to 76 who were involved in three studies. Everyone was free of heart disease at the start of the analysis. The researchers categorized the people according to their blood levels of vitamin K, and compared that information with rates of heart disease and death over 13 years. The results showed no definite link between vitamin K levels and heart disease. However, people with the lowest vitamin K levels were 19% more likely to die during the study period than those whose K levels were adequate.

The exact reason for the link between low vitamin K and a higher death rate is unclear. But scientists know that vitamin K helps prevent calcium buildup in arteries, which is associated with decreased blood flow throughout the body. Other studies have shown a link between low levels of vitamin K and a higher risk of osteoarthritis; that condition can affect mobility and increase falls, which can also contribute to earlier death.

Guidelines suggest men get 120 micrograms (mcg) of vitamin K per day, but more than 60% of men ages 70 and older do not, according to a survey conducted by the study's researchers. Vitamin K is found in broccoli and leafy greens like kale and spinach, and in vegetable oils like soybean and canola. A cup of leafy green vegetables has more than 120 mcg, and a tablespoon of soybean oil offers 25 mcg.

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