RDA for vitamin D is not enough
The standard recommended daily allowance (RDA) for vitamin D is insufficient for preventing fractures, concluded researchers at Harvard School of Public Health.
A meta-analysis by the team found that the recommended 400 IU of vitamin D did not reduce the risk of fractures in the over-60s. But, when the dose was doubled to 700-800 IU, hip-fracture risk fell by 26 per cent, and by 23 per cent for non-backbone fractures.