It's old blood, not old bones, that makes fracture healing difficult among the elderly

Why do vampires from Dracula to Angel seem to crave the blood of the young and beautiful? The undead may be onto something. Young blood, it seems, has special healing properties that have been lost in older blood. A recent finding by scientists from the Hospital for Sick Children, Toronto, and Duke University challenges long-held ideas about why our bones have a harder time healing as we age. Their research discovered that old mouse bones mend like youthful bones do when they're exposed to...

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