Obesity-Induced Effects on Bone Metabolism

Obesity profoundly alters skeletal homeostasis through a combination of mechanical, hormonal and inflammatory pathways. While increased body mass imposes greater mechanical loading that can initially stimulate bone formation, excessive adiposity shifts mesenchymal stem cell fate toward adipogenesis at the expense of osteoblast differentiation, leading to compromised bone quality. Expansion of bone marrow adipose tissue (BMAT) not only reduces space for bone-forming cells but also secretes adipokines and proinflammatory mediators that enhance osteoclast activity and bone resorption. Chronic low-grade inflammation, marked by elevated cytokines such as interleukin-6, further disrupts the balance of bone remodelling. Nutritional factors associated with obesity impair calcium absorption and mitochondrial function in bone cells through increased reactive oxygen species. Collectively, these alterations culminate in reduced trabecular and cortical bone strength, delayed fracture healing and greater fragility fracture risk. Understanding the interplay of marrow adiposity, immune modulation and endocrine signalling is essential for developing targeted interventions to preserve skeletal health in the context of obesity.

Research from Nature Portfolio

High-resolution microfocus X-ray imaging has provided unprecedented insights into obesity-driven changes in bone microarchitecture in a mouse model of type 2 diabetes. In obese, insulin-resistant animals, trabecular thickness increased but trabecular number decreased, indicating a shift toward fewer, thicker struts that may impair load distribution. Ultra-high-resolution assessment of cortical bone uncovered a reduction in vascular porosity at submicrometre scale, suggesting compromised nutrient delivery and waste removal within the cortex. These findings highlight that metabolic conditions associated with adiposity not only alter trabecular geometry but also reduce cortical vascular channels, potentially undermining bone remodelling and resilience.

Obesity-Induced Effects on Bone Metabolism publication trend

The graph below shows the total number of articles in obesity-induced effects on bone metabolism across all publications each year (not limited to Nature Index journals).

Technical terms

Bone marrow adipose tissue (BMAT): Fat cells within the bone marrow influencing skeletal remodelling.

Mesenchymal stem cell (MSC): Multipotent progenitor in marrow capable of generating osteoblasts or adipocytes.

Osteoblast: Bone-forming cell responsible for synthesising bone matrix.

Osteoclast: Bone-resorbing cell involved in degrading bone tissue.

Adipokine: Bioactive protein secreted by fat cells affecting metabolism and inflammation.

Trabecular bone: Spongy inner bone with a porous architecture critical for strength and metabolism.

Vitamin D receptor (VDR): Nuclear receptor mediating vitamin D effects on cell function including bone cells.

References

1. Effects of obesity on bone metabolism. Journal of Orthopaedic Surgery and Research (2011).
2. High‐Fat Diet–Induced Obesity Promotes Expansion of Bone Marrow Adipose Tissue and Impairs Skeletal Stem Cell Functions in Mice. Journal of Bone and Mineral Research (2018).
3. Obesity-Induced Changes in Bone Marrow Homeostasis. Frontiers in Endocrinology (2020).
4. Changes in bone macro- and microstructure in diabetic obese mice revealed by high resolution microfocus X-ray computed tomography. Scientific Reports (2016).
5. Multiomics profiling reveals VDR as a central regulator of mesenchymal stem cell senescence with a known association with osteoporosis after high-fat diet exposure. International Journal of Oral Science (2024).
6. Interleukin-6 Knockout Inhibits Senescence of Bone Mesenchymal Stem Cells in High-Fat Diet-Induced Bone Loss. Frontiers in Endocrinology (2021).
7. High-fat diet causes undesirable bone regeneration by altering the bone marrow environment in rats. Frontiers in Endocrinology (2023).