Lithium maintains production of a bone-repair protein, suggesting that the element might help people with fractures that are mending slowly or not at all.
Scientists had known that the protein beta-catenin is instrumental in orchestrating bone growth in childhood. But it was less clear whether beta-catenin played such a role in bone repair.
Meanwhile, other research had shown that lithium increases the amount of beta-catenin in the body by preventing its degradation.
Researchers at the Hospital for Sick Children in Toronto decided to test lithium's possible effect on healing rates in mice with broken leg bones. It helped the healing process when given a few days after a break, but not when given earlier, the scientists report in the July PLoS Medicine.