Vitamin K1 can be taken orally by consuming a good multivitamin & mineral formula (MVM) that contains ~50-100mcgs of vitamin K (as phytonadione). The only reason you would take Vitamin K differently is because your doctor diagnosed a condition requiring greater amounts and/or injections. Low levels of vitamins K and D have been associated with a higher risk of cardiovascular disease including hardening of the arteries. Specifically vitamin K deficiency has been linked to age-associated conditions including bone fragility after estrogen loss (osteocalcin) and arterial calcification (hardening of arteries), a predictor of cardiovascular disease. In fact, a recent study found that supplementation with vitamin K significantly slowed the natural progression of coronary artery calcification (CAC). While it’s too soon to say that by taking vitamin K and D supplements you will prevent hardening of the arteries, it’s not too soon to say you should make sure you are getting enough of both these important vitamins for many health reasons including hedging your bets against CV diseases and others. The best way to insure you meet the proper levels (vitamin K ~110mcgs/day; vitamin D ~1000ius/day) is to eat the best you can including green leafy vegetables and take a daily multivitamin and mineral formula containing 600-1000ius of D and 50mcgs of K. If you are on blood thinning medication (e.g. warfarin, etc.), check with your doctor regarding taking any supplement containing vitamin K.