Numerous reports discuss the importance of maintaining strong and healthy bones.  While calcium is important for bone health, Vitamin K is also essential and assists in the formation of bone protein and is associated with higher bone density.  Without vitamin K, the bone protein (osteocalcin) lacks the structural integrity and can fracture more easily.

A recent analysis examined 7 studies involving vitamin K intake.  Participants were randomly divided into groups receiving either a vitamin K supplement or a placebo.  Individuals receiving the vitamin K supplement showed a significant increase in bone mineral content along with a dramatic decrease in fracture rates compared to those receiving a placebo.

• Hip fractures decreased by 77%;
• Vertebral fractures decreased by 60%;
• All nonvertebral fracture rates decreased by 81%

In addition, when the number of participants of all 7 studies was combined with their fracture rates, researchers found vitamin K to have strong protective effects for bone health.  Furthermore, because vitamin K is an essential nutrient of the body, no serious adverse events were reported with this treatment method that can sometimes occur with other osteoporosis medications.

What it Means:

The researchers encourage patients who are at risk for fractures to consume a diet rich in vitamin K, which is primarily found in cabbage, cauliflower, spinach and other green leafy vegetables, cereals, and soybeans.

In addition, individuals wanting strong, healthy bones throughout their lifetime would be wise to also consume a diet rich in vitamin K.

Important Consideration:

People who are taking warfarin, a blood thinner, should be aware that vitamin K may reduce the effectiveness of this medication; this includes supplements as well as foods rich in vitamin K.  If you are taking warfarin, make sure to consult your healthcare provider before increasing your intake.

Recommended Vitamin K Intake and Sources:

The current Adequate Intake (AI) for vitamin K is 90 mcg for women, and 120 mcg for men. However, the Women’s Health Study and the Framingham Heart Study showed that persons getting 250+ mcg/day had significantly lower rates of fractures.

Food	Serving Size	Vitamin K Content (mcg)
Asparagus	½ cup cooked	46
Broccoli	1 cup cooked	420
Brussels Sprouts	1 cup cooked	547
Cabbage	1 cup cooked	73
Kale, raw	1 cup, chopped	547
Leaf Lettuce, raw	1 cup, chopped	118
Parsley, raw	1 cup, chopped	324
Soybean Oil	1 tablespoon	26
Spinach, raw	1 cup, chopped	120
Spinach, cooked	½ cup	444
Swiss Chard, raw	1 cup, chopped	299
Watercress, raw	1 cup, chopped	89

Sources:  Cockayne S, et al. (June 2006). Vitamin K and the Prevention of Fractures. Archives of Internal Medicine, 166:1256-1261; Oregon State University. Micronutrient Information Center website (2006).