An important analysis conducted by Children's Hospital Oakland Research Institute scientists suggests the importance of ensuring optimal dietary intakes of vitamin K to prevent age-related conditions such as bone fragility, arterial and kidney calcification, cardiovascular disease, and possibly cancer. Vitamin K is concentrated in dark green plants such as spinach or Swiss chard, and is either not present or present in only small amounts in most multivitamin pills.

Vitamin K slowed the development of insulin resistance in elderly men in a study of 355 non-diabetic men and women ages 60 to 80 who completed a three-year clinical trial at the Jean Mayer Human Nutrition Research Center on Aging at Tufts University (USDA HNRCA).

In a randomized controlled trial called the "Evaluate the Clinical use of vitamin K Supplementation in Postmenopausal Women with Osteopenia" (ECKO) trial, Angela Cheung and colleagues at the University of Toronto found that a high dose daily vitamin K1 supplement did not protect against age-related bone mineral density (BMD) decline.