Depression is a significant risk factor for low bone mass in pre-menopausal women, and may be as important as smoking and reduced calcium intake, a study published by the Archives of Internal Medicine has suggested.

The US study investigated bone densities in 89 pre-menopausal women with major depressive disorder and 44 healthy controls.

The researchers found low bone density in the femoral neck of 17 per cent of the subjects with depressive disorder, compared with 2 per cent among the controls.

Large differences in the prevalence of bone density were also seen at the lumbar spine and hip.

The study authors also found increased levels of pro-inflammatory cytokines and reduced levels of anti-inflammatory cytokines, and said that their possible contribution to  low bone mass in pre-menopausal women remained to be clarified.