Vitamin K is a fat-soluble vitamin that plays an important role in blood clotting. Joyce McCann, from Children's Hospital Oakland Research Institute (California), and colleagues analyzed data from hundreds of published articles dating back to the 1970's and conclude that current recommendations for vitamin K intakes need to be increased to ensure optimal health. This conclusion is basesd on the triage theory, which proposes that some functions of micronutrients (essential vitamins, minerals, fatty acids, and amino acids) are restricted during shortage and that functions required for short-term survival take precedence over those that are less essential. As a result, undesireable changes accumulate as a consequence of restriction, which in-turn increases the risk of diseases of aging. In this model, the team submits that: "A triage perspective reinforces recommendations of some experts that much of the population and warfarin/coumadin patients may not receive sufficient vitamin K for optimal function of vitamin K–dependent proteins that are important to maintain long-term health."