Staying indoors too long can weaken bones, warns orthopaedic surgeon

Orthopaedic surgeon Dr Sumit Badhwar says long days spent at desks, in cars and air-conditioned rooms deprive bones of sunlight, movement and nutrition. Less sun means less vitamin D, so calcium is poorly absorbed, and glass windows block most UVB rays. Long sitting also removes the load bones need to strengthen, a problem now affecting people in their 20s and 30s.