Studies have shown a direct relationship between tobacco use and decreased bone density. It is hard to determine whether a decrease in bone density is due to smoking itself or to other risk factors common among smokers. For example, in many cases smokers are thinner than nonsmokers, tend to drink more alcohol, may be less physically active, and have poor diets. Women who smoke also tend to have an earlier menopause than nonsmokers. These factors place many smokers at an increased risk for osteoporosis apart from their tobacco use.
In addition, studies on the effects of smoking suggest that smoking increases the risk of having a fracture. As well, smoking has been shown to have a negative impact on bone healing after fracture.