The burden of osteoporosis is increasing in all societies. In comparison with other organs or apparatuses fewer studies have focused on incorrect lifestyles and bone. This article reviews clinical and experimental studies on the effects of obesity, alcohol abuse and smoking on bone. Overweight and obesity protect bone, thus reducing the fracture risk and the development of osteoporosis in older adults. However, extreme obesity (body mass index more than 40 kilogram/meter squared) seems to be a risk factor for osteoporosis. Moderate alcohol consumption may have a protective effect, whereas excessive consumption is an important risk factor. Cytokines are the main mediators of the detrimental effects of obesity and alcohol. Smoking contributes to bone loss and fracture probably by interfering with estrogens, calcium and vitamin D. Health information campaigns against these harmful lifestyles should be strengthened by using available scientific information to increase awareness about their consequences on the bone.