Introduction

Osteoporosis is becoming one of the most common chronic diseases affecting millions of people worldwide, primarily due to the aging of the world's population. Since bone fractures are closely related to diminished bone mass and reduced bone mineral density, we have to identify all underlying causes responsible for inadequate accumulation of bone tissue during skeletal growth and consolidation, and excessive losses thereafter. Maximizing bone mass during skeletal growth, therefore, has been the goal of the primary prevention of osteoporosis, while the reduction of bone loss during menopause and aging is the problem in secondary prevention programs. Until recently, the concern for patients with osteoporosis dictated a simple approach to preventive medicine, that is to reduce the number of women suffering from it. They were considered the minority, while the majority of the population without fractures was considered normal. This approach was primarily based on the X-ray diagnosis which assumed that women fall into just two categories, namely those who have the disease and those who do not (Matkovic et al., 1995b). That there is no clear distinction between the bone health and osteoporosis was originally proposed by Newton-John and Morgan (1970) and shown for the first time in a study of fracture rates among two populations with different peak bone mass (Matkovic et al., 1979).