Chronic inflammation and bone health
- Mar 2
- 6 min read
Updated: 3 days ago
Inflammation & Bone Health - Part 1 of 3
How persistent inflammation disrupts bone remodelling and affects bone density
In Brief
Inflammation is part of normal repair. Problems arise when inflammatory signals stay active for too long.
In bone, persistent inflammation may encourage osteoclasts, the cells that break down old bone, to become more active. It may also make it harder for osteoblasts, the cells that build new bone, to keep pace.
This can shift bone remodelling towards greater breakdown, which may contribute to lower bone density and higher osteoporosis risk alongside age, hormones, medication, movement, nutrition and medical history.
This article explains:
This article is the first in a short series exploring the relationship between inflammation and bone density.
When people search for how to improve bone density or prevent osteoporosis, the focus is often on calcium, vitamin D, or menopause. Yet another important factor plays a major role in bone remodelling: chronic, low-grade inflammation.
This raises an important question: can inflammation contribute to osteoporosis, and how does it affect bone density over time?
What is inflammation and how does it affect bone health?
Inflammation is not inherently harmful it is a vital part of tissue repair. To understand its role, imagine the immune system acting as a site inspector. When damage or infection is detected, the site inspector issues a "repair notice", this is inflammation.
In a healthy system, a repair notice is temporary. It alerts the body that attention is needed so repair can take place. Once the work is complete, the notice is resolved, and the site returns to its normal routine.
Problems arise when inflammation persists unnecessarily, keeping the site in a constant state of repair, even when no urgent fix is required. When inflammation remains active at a low level for long periods, often described as low-grade chronic inflammation, the body stays in a prolonged state of immune activation.
Over time, this persistent signalling can begin to disrupt normal repair processes in many tissues, including bone.
Bone is living tissue and responds to immune signals
Bone is not a static structure. It behaves more like a construction site, where old material is continuously removed and replaced with new bone in a process called bone remodelling. Two cell types manage this work:
Osteoclasts (the demolition crew): these cells break down and remove old or damaged bone.
Osteoblasts (the builders): these cells lay down new bone.
In a healthy environment, these cells work in balance, removing old bone while rebuilding new, keeping bone density stable.
However, they do not work in isolation. They are highly responsive to the repair notices (inflammatory signals) present in their environment.
How persistent inflammatory signalling leads to bone loss
When inflammatory signals remain active for long periods, the balance on the construction site shifts:
Impaired building: Osteoblasts (the builders) need stable, well-regulated conditions to construct new bone efficiently. When repair notices keep appearing, the site never returns to its normal rhythm. These signals interfere with the builders’ ability to produce new bone, slowing the process. A review of cytokine effects on bone remodelling in osteoporosis describes how sustained high levels of inflammatory cytokines suppress osteoblast function and bone formation.
Increased demolition: Conversely, osteoclasts (the demolition crew) are stimulated by inflammatory signals. As these signals persist, they become more active, breaking down bone faster than it can be replaced. The same review sets out how cytokines such as TNF-α and IL-6 promote osteoclast formation and bone resorption.
Over time, this creates an imbalance where breakdown outpaces rebuilding.
What sustains low-grade inflammation
For many people, this inflammatory load is driven by a combination of subtle influences that affect immune regulation over time.
Common drivers of chronic inflammation include:
Gut barrier dysfunction or microbiome imbalances
Diets high in processed foods and low in nutrients that support bone health
Chronic psychological stress
Poor sleep
Metabolic dysregulation
Individually, these factors may not cause obvious symptoms, but together they can lead to frequent or prolonged inflammation within the body.
What the research shows about inflammation and bone loss
The link between the immune system and bone density is well-documented in clinical settings:
Chronic inflammatory conditions, such as rheumatoid arthritis, are consistently associated with increased fracture risk and accelerated bone loss. A 2017 meta-analysis of fracture risk in rheumatoid arthritis found a significantly higher fracture risk in patients with the condition than in those without.
Elevated inflammatory markers, including interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α), have been linked to reduced bone mineral density in both ageing populations and postmenopausal women. The Framingham Offspring cohort examined this association across men and women, and a systematic review and meta-analysis of IL-6 and TNF-α in postmenopausal osteoporosis found both markers significantly raised in postmenopausal patients.
Inflammaging is a term used by researchers to describe the low-grade, persistent inflammatory state associated with ageing that directly influences bone remodelling. A 2025 review of immunosenescence and bone fragility describes how this state shifts bone remodelling toward net loss with age.
Why inflammation matters for supporting bone health and reducing osteoporosis risk
Understanding this connection helps explain why bone health is not just about calcium intake. It is about the broader physiological environment in which bone cells are trying to build and repair. Managing inflammation is a foundational, systems-based approach to protecting skeletal strength over the long term.
In Part 2, we explore the molecular pathways through which inflammation drives bone loss — including the signalling systems that accelerate bone breakdown.
Frequently asked questions
Can chronic inflammation lead to osteoporosis?
Chronic, low-grade inflammation may contribute to bone loss by changing how bone is broken down and rebuilt. It is one factor among several that can influence osteoporosis risk.
While acute (short-term) inflammation is a vital part of the body’s normal immune response to infection or repair, persistent inflammation can disrupt the natural balance of bone renewal.
Over time, this may shift the balance of bone remodelling, increasing bone breakdown relative to bone formation, leading to a gradual decline in bone mineral density and an increased fracture risk.
How exactly does inflammation cause bone loss and reduced bone density?
Inflammation can affect bone density by shifting the balance between the cells that build bone and those that clear it away.
In a healthy body, "builder" cells (osteoblasts) and "clearing" cells (osteoclasts) work in harmony. However, inflammatory signals can over-activate osteoclasts, causing them to remove bone mineral more excessively. Simultaneously, these signals can impair osteoblast function, reducing the body’s ability to build new bone.
Are inflammatory conditions like rheumatoid arthritis or Crohn's disease linked to osteoporosis?
Yes, systemic inflammatory disorders such as rheumatoid arthritis, Crohn’s disease and lupus are closely linked to accelerated bone loss and osteoporosis.
These conditions involve elevated levels of inflammatory markers, such as IL-6 and TNF-a, which circulate through the body and directly interfere with bone metabolism. Consequently, individuals with chronic inflammatory conditions often experience a faster decline in bone density (bone mass) regardless of their calcium and vitamin D intake.
What are the main causes of chronic inflammation in the body?
Chronic inflammation is often driven by a combination of lifestyle and metabolic factors, including gut health imbalances, diet, poor sleep and chronic psychological stress.
Unlike the short-term immune response triggered by an injury, this low-grade state can be sustained by a diet high in processed foods, poor sleep and inflammaging (the natural rise in inflammatory markers with age). Together, these factors keep the immune system in a state of constant activation, which can silently degrade bone health over many years.
Over time, this ongoing inflammatory state can influence bone remodelling and contribute to reduced bone density.
Structured guidance for bone health
Understanding how chronic inflammation influences bone remodelling is an important first step. The challenge is translating this into clear, practical decisions, particularly when inflammation is driven by multiple, overlapping factors.
The Nutrition for Bone Health Guide brings these mechanisms together into a structured, evidence-led approach, helping you apply them in a way that fits your health, lifestyle, and medical context.
Read the full inflammation and bone health series
This article is part of a three-part series on inflammation and bone health:
Part 1 (current): Chronic inflammation and bone health
Part 3: How gut health, stress and metabolism affect bone density
Together, these articles provide a structured overview of how inflammation influences bone health and osteoporosis risk.
Disclaimer
The information in this article is for general educational purposes. It is not intended to diagnose, treat, or replace medical advice. Bone health is influenced by many factors, and individual circumstances vary.
If you have been diagnosed with osteopenia or osteoporosis, or are taking medication that affects bone health, continue to work with your GP, consultant, or specialist team. Nutritional therapy is intended to support, not replace, medical care.
For personalised guidance, consult a registered nutritional therapist or other qualified health professional who can assess your full clinical picture.
References
Deng, Z. et al. (2023) 'The effect of cytokines on osteoblasts and osteoclasts in bone remodeling in osteoporosis: a review', Frontiers in Immunology. Available at: https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1222129/full
Xue, A. et al. (2017) 'Bone fracture risk in patients with rheumatoid arthritis: a meta-analysis', Medicine. Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC6393106/
Huang, X. et al. (2024) 'Association between postmenopausal osteoporosis and IL-6, TNF-α: a systematic review and meta-analysis', Combinatorial Chemistry & High Throughput Screening. Available at: https://dx.doi.org/10.2174/0113862073262645231121025911
Cheng, X. et al. (2025) 'Immunoporosis: the hidden link between aging immune cells and bone fragility', Journal of Orthopaedic Translation. Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC12417214/
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