A big question remains: Will lowering homocysteine levels cut the risk of fracture? The jury is still out. But as folate and other B vitamins (B6 and B12) cut homocysteine levels, good nutrition appears more important than ever.
The studies -- along with an editorial -- appear in the May 13 issue of The New England Journal of Medicine.
"Whether it is a culprit or a bystander, homocysteine can now be added to the growing list of risk factors for fractures," writes editorialist Lawrence G. Raisz, MD, of the University of Connecticut Center for Osteoporosis.
Direct Cause of Fracture -- or Risk Factor?
Homocysteine occurs naturally in the blood. Levels rise to high levels in people who don't get enough folic acid and other B vitamins. Homocysteine has been linked to heart disease. Now it is linked to bone fracture, too.
The evidence is circumstantial -- but very strong, researchers say. Studies in the U.S. and in the Netherlands involving thousands of people aged 55 and older show the same thing. Compared with people with the lowest homocysteine levels:
- Men with the highest homocysteine levels have a fourfold higher risk of bone fracture.
- Women with the highest homocysteine levels double their risk of bone fracture.
Homocysteine might cause bone loss by interfering with the way new bone forms. But that has never been conclusively proven. It might be that homocysteine is just a marker for another problem.
So while the experts argue about exactly what's going on with homocysteine, one thing is already sure: Proper nutrition is a good way to reduce your risk of fracture. Add regular exercise, and you're going to cut your risk even more.