Vitamin K is most notable for its involvement in blood clotting, but it also plays a role in bone formation. Vitamin K is absorbed through the intestines from food that we eat and is also produced by some normal gut bacteria.
Sometimes, but very rarely, newborns acquire hemorrhagic bleeding within a few months of being born. Vitamin K deficiency at birth is the recognized cause of this disorder. The problem only occurs in exclusively breastfed infants because bottle fed infants receive vitamin K supplementation in their bottles. Maternal supplementation with vitamin K works, but the mother has to remember to take the supplements. The current policy is to take no chances, cast as wide a net as possible, and give all newborns a bolus dose of vitamin K before they leave the hospital.
After this policy was implemented, it was discovered that infants receiving vitamin K injections at birth developed leukemia at higher rates than infants who did not receive the injection. Much research was published trying to confirm and/or dispute this observation. Only recently was the mechanism discovered elucidating the role of vitamin K in causing cancer. Vitamin K has important benefits, but it does in fact also cause cancer. It turns out that the low vitamin K levels in newborns is not a deficiency, but rather, it’s protective. Humans have evolved the optimum balance so that newborns have low levels of vitamin K, and then those levels slowly rise throughout the first year of life. The bolus dose of vitamin K given to newborns immediately after they are born can disrupt this optimum balance.
Hemorrhagic bleeding is a rare but terrible outcome from low vitamin K levels. But it might be smarter to confront this problem with maternal supplementation in babies who are exclusively breastfed. Bolus doses of vitamin K to all newborns could potentially cause more health problems than they are solving. At the very least, it deserves a more critical look, given our newer, better understanding of vitamin K’s capacity to cause cancer and the importance of relative concentrations in newborns.
How to increase your vitamin K intake
- Food: The vitamin K form needed for clotting, and important for breastfeeding mothers, is found in green leafy vegetables like turnip greens broccoli, kale, spinach, cabbage and asparagus.The vitamin K needed for bone health (vit K2) is found in meat sources like eggs and butter.
- Increase Good Gut Bacteria: Vitamin K2, the kind important for bones, is also produced by bacteria in your gut. Eating fermented foods like cheese can help support this bacteria.
- Supplements: Like many vitamins, vitamin K is also available in supplement form.
People who are taking anticoagulants (blood thinners) should talk to their doctors prior to eating foods high in vitamin K. This vitamin may reduce the efficacy of some of these medications.
Some medications that can interfere with vitamin K absorption from the intestines are antibiotics, Phenytoin (Dilantin), and cholesterol-lowering medications.