March 27, 2007

Does strontium help make bones stronger?

Hamilton, ON - Researchers developing a new technique that can measure strontium levels non-invasively have stumbled across an intriguing phenomenon: higher levels of strontium appear in Asians, suggesting the possibility that strong bones depend on where you’re born and what you eat.

The findings are published today in the U.K.-based journal Physics in Medicine and Biology.

Strontium is a chemical element naturally present in water and soil, and enters the human body through the food chain. Being a bone seeker like calcium, it accumulates in the skeleton where more than 99 per cent of it is stored.

Strontium supplements appear to reduce the incidence of bone fractures and improve bone density; therefore the chemical holds the promise of being an effective treatment for osteoporosis. Osteoporosis is a major public health issue, affecting 44% of American women and 11% of American men over 50 years of age.

“The way strontium exerts its beneficial effects is not completely understood but this new technique we’ve developed, will allow us to understand the dynamics of strontium and how it reacts with bones,” says Mariangela Zamburlini, a graduate student in the Department of Medical Physics and Applied Radiation Sciences at McMaster University, and the study’s lead researcher. “Perhaps we’ll gain insights on why some people benefit from the treatment and some others do not.”

Zamburlini developed an X-ray fluorescence system that activates the strontium atoms in the bone. She used it on healthy volunteers with no history of strontium intake. That’s when she noticed that the volunteers of Asian decent had higher strontium levels than Caucasians.

“The results present a bit of a paradox,” says David Chettle, associate dean for research in McMaster’s Faculty of Science who was involved in the study. “East Asians have a lower bone density than North Americans, and yet they also have a lower incidence of osteoporosis. Is this due to an East Asian diet that naturally elevates strontium levels? Or is it due to genetics or perhaps to environmental factors?”

Funding for the study was made possible by grants from the Natural Sciences and Engineering Research Council, from the Ontario Graduate Scholarship program, and from Canada Foundation for Innovation/Ontario Innovation Trust. The research was done in collaboration with Ryerson University’s associate professor of physics Ana Pejovic-Milic.