To examine the demineralizing effects of the ageing process on the human skeleton, a photon absorptiometric method was employed which measured bone mineral mass. Rates and amounts of demineralization were compared in two prehistoric Indian populations: Indian Knoll (dated between 2500 and 2000 B.C.) of the Archaic Period and Pete Klunk (dated between 50 B.C. and 250 A.D.) of the Middle Woodland or Woodland or Hopewell Period. The former was exclusively a hunting and gathering group while the latter supplemented its hunting and gathering with part-time agriculture. Archaeological and osteometric data suggest that Hopewell had a more nutritionally adequate and reliable diet than Indian Knoll.
By regression slope analysis it was shown that, as in modern populations, trabecular and female rates of loss are greater, respectively, than cortical or male rates. Hopewell males and females lost bone at a faster rate than Indian Knoll males and females. When amounts of demineralization in these two groups were compared to that of a contemporary group, the Indian Knoll and contemporary populations were found to lose the same amount while Hopewell lost the greatest amount. It is suggested from these comparisons that dietary sufficency does not contribute significantly to skeletal maintenance during ageing.