A chronic high-fat (sugar-free) diet worsened cancellous, but not cortical, bone development in young male rats.

The addition of fructose to a high-fat diet did not exacerbate cancellous bone loss.

Both diets stimulated bone marrow adipogenesis, increased leptin, and reduced antioxidant capacity, changes associated with adverse cancellous bone development.

The high-fat/high-fructose diet lowered osteoblast number and circulating osteocalcin, a change associated with circulating leptin.