Although bone mass normally declines progressively after the age of 35, bone loss severe enough to cause fractures after minimal trauma seems to be a relatively new phenomenon. Osteoporosis was rare in the late 19th century, and it was not until around 1920 that the condition began to attract attention among pathologists. Since that time, osteoporosis prevalence has increased progressively, even after adjusting for age. For example, the age-adjusted prevalence of osteoporosis in England and Sweden doubled between 1950 and 1980.[i] [ii] [iii] In addition, the prevalence of osteoporosis among elderly people in some developing countries is lower than that of elderly Americans, despite lower calcium intakes in those countries, further suggesting that osteoporosis is a disease of modern civilization.[iv]
[i] Boyce WJ, Vessey MP. Rising incidence of fracture of the proximal femur. Lancet 1985;1:150-151.
[ii] Johnell O, Nilsson B, Obrant K, Sernbo I. Age and sex patterns of hip fracture – changes in 30 years. Acta Orthop Scand 1984;55:290-292.
[iii] Bengner U, Johnell O. Increasing incidence of forearm fractures. A comparison of epidemiologic patterns 25 years apart. Acta Orthop Scand 1985;56:158-160.
[iv] Zeegelaar FJ, Sanchez H, Luyken R, Luyken-Koning FWM, van Staveren WA. Studies on physiology of nutrition in Surinam. XI. The skeleton of aged people in Surinam. Am J Clin Nutr 1967;20:43-45.