Science, 25 July 2024
There’s growing evidence that breathing polluted air increases the risk of osteoporosis
Down to the Bone
Ganeshwadi, India — Rajashree Khatave has lost count of the painkillers she has taken since she first experienced knee pain a decade ago. “Within a few days, I couldn’t walk properly and often fell,” recalls the 51-year-old resident of this village on the Krishna River in western India. In an effort to ease the pain, Khatave consulted with faith healers and massaged her knees with oils. Eventually, a doctor determined she had osteoporosis, a disease in which bones lose their density and mass, making them brittle and vulnerable to fracturing.
Researchers have called osteoporosis a “silent” disease because it often isn’t recognized until a person suffers a debilitating injury. But it is widespread: Globally, an estimated one-third of women and one-fifth of men over age 50 will experience fractures related to osteoporosis. In India, reliable statistics are scarce, but more than 61 million people are believed to have the condition.
Research suggests many factors contribute to osteoporosis, including hormonal changes, a lack of exercise, and drinking alcohol and smoking tobacco. All play a role in India, but so may another factor: exposure to air pollution. Epidemiological studies in numerous nations suggest rates of osteoporosis are higher in areas that have sooty, highly polluted air—for which Indian cities and villages have become notorious. Researchers are still trying to understand the biological mechanisms that might link smog to brittle bones. But, “There is growing recognition that … air pollution is a risk factor for bone health,” says environmental epidemiologist Cathryn Tonne of the Barcelona Institute for Global Health (ISGlobal).