Banking Bones

Have you saved-up enough bone tissue for your retirement? By your mid-20s, your bone mass and density will have peaked, only to drop with age as bones lose more minerals than they can take up. Load-bearing exercise, like running, rather than swimming, and a healthy diet can stave off bone-wasting diseases like osteoporosis. Gentle stress on the bones helps new bone-cells, or osteoblasts (pink), to develop and prompts the soft unmineralised bone matrix (orange-brown) that the cells produce to harden into solid bone (black) by fixing minerals like calcium and phosphate. Failure of this crucial step, as in some genetic disorders like neurofibromatosis type I, can lead to frequent bone fractures and excessive growth of soft bone tissue, treated by remedial surgery or amputation when severe. Future therapies with enzymes like asfotase alpha, which encourages calcium uptake in bones, are undergoing clinical trials and hold promise for effective and less invasive treatment.

Written by Tristan Farrow

Tristan Farrow

Writer

British Science Association Media Fellow. He holds a degree in quantum physics from the University of Cambridge and a Research Fellowship in quantum effects in biology.

• Image by Florent Elefteriou
• Vanderbilt University Medical Center, USA
• Originally published under a Creative Commons Licence
• Research published in Nature Medicine, July 2014