[Positive and negative effect of exogenous fat on the bone mineral density in healthy women by dual energy X-ray absorptiometer].

Objective: To examine the influence of exogenous fat (lard) on the bone mineral density (BMD) of lumbar spine measured by dual energy X-ray absorptiometer (DXA) Hologic QDR 4500A in different sites in healthy women.

Methods: Lard packets (5 cm or 10 cm thick) were prepared. The lumbar spine (LS) DXA scans were performed on 37 women(Group A), who were repeated with lard packets (5 cm or 10 cm thick) placed over the abdomen, and the hip DXA scans were performed on 18 women(Group B), who were repeated with lard packets (5 cm or 10 cm thick) placed over the left thigh. Whole body DXA scans were performed on 8 women(Group C), who were repeated with 5 cm thick lard packets over the abdomen. The pair t-test was used to compare the value of BMD with and without lard.

Results: After lard was placed over abdomen, the bone area (BA), bone mineral content (BMC), and BMD of the LS decreased significantly (P<0.001);at the hip, BA had no significant change, but the BMC and BMD of the neck, trochanter, and inter trochanter increased significantly (P<0.01~0.05). The BMD of the whole body had no significant change (P>0.05).

Conclusion: Lard impacted the BMD by DXA Hologic QDR 4500A, BMD of the LS significantly decreases, but BMD of the whole body has no significant change. BMD of the hip significantly increases with lard.