Prevent hip fractures with ample vitamin K

Nutritional Rescue

In a fight between Godzilla and Superman, who wins?

You may have played this sort of game before – especially if you’re a male who’s ever driven cross-country with your best friend. And sports fans do it all the time: The ’72 Dolphins or the ’08 Patriots? (Sorry, New England – I’m going to have to go with the Dolphins.)

Today we have one of those matchups in the world of preventive nutrition. And it’s a formidable contest: In the prevention of hip fracture, which of these four nutrients appears to offer the greatest protection?

1) Calcium
2) Vitamin D
3) Magnesium
4) Vitamin K

This is a tough one because each is absolutely necessary for maintaining healthy bones – especially in later years. But according to a new study from Japan, one of these stands out above the rest.

And in this corner

Noting that hip fracture rates are consistently higher in some regions of Japan compared to other regions, researchers at Japan’s Iwate Medical University devised a study to assess the effect of nutrients on hip fracture risk.

STUDY PROFILE

• Japan was divided into 12 regions
• Data from a 2002 national survey revealed occurrences of hip fracture in each of the regions
• The National Nutritional Survey of Japan supplied data regarding average nutritional intakes for each region
• When hip fracture rates and nutritional intakes were compared, high intakes of magnesium and vitamins D and K were linked to lower risk of hip fracture among both men and women
• High intake of calcium was linked to lower hip fracture risk among women, but not quite as strongly in men

And the big winner? In both men and women, risk of hip fracture was lowest in regions with the highest intake of vitamin K.

Get your K on

As noted in previous e-Alerts, research in recent years has revealed the important connection between vitamin K intake and bone health.

Alternative health care pioneer Jonathan V. Wright, M.D., has long recommended vitamin K supplements for those with a family history of osteoporosis or arteriosclerosis (narrowing of the arteries). Dr. Wright suggests 5 to 15 mg of vitamin K per day – considerably higher than the current RDA, which is 80 micrograms for men, and 70 for women.

Before supplementing with vitamin K, talk to your doctor about this important vitamin and its different forms. HSI Panelist Allan Spreen, M.D.: “The synthetic form (K3, or menadione) has caused some liver toxicity and, rarely, a form of anemia when taken in high doses. There’s also K2 (or menaquinones), but K1 and K2 are fine. As usual, it seems best to avoid synthetic forms, if possible. If the individual is on coumadin (blood thinner), he needs to talk with his doctor, as vitamin K can interfere with its effect.”

Almost all of our dietary intake of vitamin K comes in the form of K1, which is mostly found in dark, leafy green vegetables, broccoli, asparagus, tomatoes, avocados, olive oil, whole wheat, butter, and green tea. Vitamin K1 is converted into K2 in the intestine, but we get some amount of K2 directly from meat, liver, egg yolk, and fermented products such as yogurt and cheese.

In the Japanese study, researchers found that one of the key sources of vitamin K was natto, which is made from fermented soy. The key word here: fermented. Most soy products sold in the U.S. are not fermented, and regular consumption may do more harm than good.

Source:
“Association of Hip Fracture Incidence and Intake of Calcium, Magnesium, Vitamin D, and Vitamin K” European Journal of Epidemiology, Vol. 23, No. 3, March 2008, springerlink.com