Alcohol

Moderate alcohol intake has no known negative effect on bone and may even be associated with higher bone density in post-menopausal women. However, alcoholism is detrimental to bone health and requires treatment when identified.
The most effective treatment for alcohol-induced bone changes is abstinence. Abstinence in alcohol seems to result in rapid recovery of osteoblast function. Moreover, studies demonstrate that bone loss may be partially restored when alcohol abuse is discontinued.

Smoking

Cigarette smoking was first identified as a risk factor of osteoporosis more than 20 years ago. Subsequent studies also demonstrated a direct relationship between smoking and decreased bone density. So, if you want to have a healthy skeleton, DON¡¦T SMOKE.

Drugs

Taking certain drungs causes bone loss

(Sources of information : National Institute of health, Osteoporosis and related bone disease- National resource center)