**5. Conclusions**

Obese postmenopausal women showed lower marker levels of bone formation, especially at younger ages. Older, obese women showed higher markers of bone resorption. This situation may be related to the fact that obese patients showed a decrease in vitamin D levels regardless of age, which is associated with a high PTH. However, an increased risk of fracture at five years was not found among obese patients.

The interaction of obesity and bone metabolism is complex due to the multitude of factors that interfere with it. The belief that obesity protects against osteoporosis is not a completely clear concept, and more studies are required to evaluate its relationship, determine its incidence, and be able to propose measures to prevent its negative influence on bone.

**Author Contributions:** Conceptualization, J.J.L.-G., J.L.P.-C. and D.A.D.L.-R.; Data curation, J.J.L.-G., I.G.d.S., M.P.-A., O.I.-J. and D.P.-M.; Formal analysis, J.J.L.-G.; Funding acquisition, D.A.D.L.-R.; Investigation, J.J.L.-G., I.G.d.S., M.P.-A., O.I.-J. and D.P.-M.; Methodology, J.J.L.-G.; Project administration, J.J.L.-G. and D.A.D.L.-R.; Resources, J.J.L.-G.; Software, J.J.L.-G.; Supervision, J.J.L.-G., J.L.P.-C. and D.A.D.L.-R.; Validation, J.J.L.-G. and D.A.D.L.-R.; Visualization, J.J.L.-G.; Writing—original draft, J.J.L.-G. and D.A.D.L.-R.; Writing—review and editing, J.J.L.-G., J.L.P.-C. and D.A.D.L.-R. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** The study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board (or Ethics Committee) of "Comité de Ética en Investigación con Medicamentos (CEIm) of East Valladolid Area (protocol PI 19-1517, septiembre 2019).

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
