Change in cortical bone thickness among 64 women with osteopenia randomised to 14-month treatment with no mineral therapy (red bar), calcium gluconate (blue bar), or calcium hydroxyapatite (green bar). Change in cortical bone thickness among 64 women with osteopenia randomised to 14-month treatment with no mineral therapy (red bar), calcium gluconate (blue bar), or calcium hydroxyapatite (green bar). The control group showed bone loss (p<0.01 compared to baseline), while the hydroxyapatite group showed bone gain (p<0.01 compared to baseline). The calcium gluconate showed no significant change.70 James H O'Keefe et al. Open Heart 2016;3:e000325 ©2016 by British Cardiovascular Society