Rameshji, though I am an advocate of alternative therapies, I also believe they complement and don't quarrel with allopathy. And allopathy is needed in special cases or emergency situations. So, in your friend's case he has to go with the doctor's advice and do the follow-up required of him. In normal course bone becomes soft usually due to lack of mobility.(In fact, a sedentary youth's bone may not be as dense as an agile old person.) Exercise and mobility challenge muscles to which the bones are attached. This in turn make the bones dense -- bones are live `factories' (that make blood cells, store key nutrients etc) and need the constant challenge of muscular movement and resistance training to remain in peak condition.Even excessive protein intake often blocks calcium absorption, affecting bone health etc. I am not sure what could be the provocation in your friend's case. I am sorry I am unable to help u, but if your friend has been advised corresponding physiotherapy, dietary advice by his ortho this would be the first line of defence against his problem. Wishing him speedy recovery..