To better understand how and why osteoporosis occurs, researchers are increasingly examining the relationship between the skeletal system and the immune system. While at first glance, immune cells might seem like a strange place to seek solutions to bone loss, decades of research have revealed that these two systems are interconnected and mutually dependent.
In this article, you'll learn about the evolving field of osteoimmunology and its implications for bone health.
We'll examine the history of this field, what it reveals about bone biology, and how these insights may pave the way for new and innovative approaches to prevent and treat osteoporosis.
Osteoimmunology Expands Our Understanding of Bone
The first evidence of the close relationship between the immune and skeletal systems emerged in 1972, in pioneering studies that identified substances in immune cells that activate osteoclasts.1
Osteoclasts are the cells responsible for breaking down old or damaged bone, allowing their counterparts, the bone-building osteoblasts, to deposit new bone tissue. The balance between these two cells, one breaking bone down and the other building it up, is essential for bone homeostasis, in which bone volume and density remain stable.
If osteoclasts outnumber or outperform osteoblasts, bone loss occurs. When osteoblasts take the lead, bone grows denser and stronger. The discovery that immune cell-derived substances activate osteoclasts revealed a potential mechanism for bone loss driven by excessive osteoclast formation and activity.
However, it was not until nearly thirty years later that two researchers published a letter in the journal Nature and coined the term osteoimmunology. This relatively young field of study seeks to understand the relationship between these two body systems.1
Osteoimmunology has continued to expand, yielding important discoveries about bone biology and the role immune cells play in osteoporosis. A quantitative review of studies on osteoimmunology and osteoporosis included a staggering 3,218 articles published between 2013 and 2022.2
Clearly, this field shows promise in the pursuit of new and better approaches to improving bone health and preventing or reversing osteoporosis.
Synopsis
Stronger Bones. Without Drugs. Guaranteed!
The natural and evidence-based program that helps reverse osteoporosis and osteopenia in 12, 6, even 3 months… guaranteed.
Osteoimmunology originated with the 1972 discovery that immune cells influence bone-resorbing osteoclasts. In the 21st century, researchers coined the term osteoimmunology and began systematically studying how these two systems interact.
Bone Cells And Immune Cells
The link between bone and immune cells begins at their creation. Both cell types can originate from the same stem cells, and once formed, they share signaling pathways.
Studies have identified regulatory molecules that the systems share, by which the immune system plays a role in healthy bone remodeling or in the development of osteoporosis. Conversely, the microenvironment of bone cells has an influence on the development and function of the immune system. The process of immune cell formation occurs in bone marrow, where hematopoietic stem cells may differentiate into all types of immune cells.1,3
Immune cells such as B cells, T cells, and dendritic cells can all influence the bone remodeling process. When the immune system is abnormally activated, it can disrupt the balance of osteoclasts and osteoblasts, leading to impaired bone remodeling. Inflammatory immune system cytokines and related molecules also regulate bone metabolism, affecting both formation and resorption.3
The hormone estrogen, which plays a significant role in post-menopausal osteoporosis, impacts bone remodeling in part through its stimulation of immune cells.1,3
Synopsis
Immune and bone cells derive from the same stem cells and share signalling pathways. Abnormal immune activation can cause imbalances in bone remodeling. The hormone estrogen impacts bone health in part through its stimulation of immune cells.
Supporting Immune Health To Support Bone Health (And Vice Versa)
Osteoimmunology provides a clear example of the interconnectedness of body systems.
Modern medicine has spent hundreds of years delineating our bodies into distinct parts, giving the false impression that these different parts are independent. That's a reductionist view of human biology. A more holistic view considers the many layers of interconnection and influence that connect the different systems that comprise the human body.
From this wider perspective, we can see how supporting immune health helps maintain strong bones, and how, conversely, healthy bones create an environment that supports robust immune function.
One study suggested that regulating key effectors of the immune system, such as the cytokines IL-1, IL-6, and tumor necrosis factor alpha (TNFα) may be beneficial for reversing and preventing osteoporosis.3 Researchers have found the two systems to be so interdependent that a 2018 study even suggested a new term for research on the immune system's role in osteoporosis: immunoporosis.4
The expansion of the field of osteoimmunology is encouraging news for Savers. It indicates that scientists are thinking deeply and broadly about the multiple causes of osteoporosis and the multiple paths to building healthier, stronger bones. As always, the Save Institute will keep you up to date on the latest developments.
Synopsis
Researchers have suggested that regulating key immune system effectors could be beneficial for reversing and preventing osteoporosis. Supporting immune health can help keep our bones strong, and conversely, healthy bones create an environment that can better support a robust immune system.
What This Means To You
Healthy bones require a healthy immune system — and the reverse may be just as true. The deep links between these two systems illustrate the importance of considering your health holistically.
The Save Institute was founded on the premise that a drug-free approach to preventing and reversing osteoporosis is not only highly effective, but also improves overall wellness, physical and cognitive function, and the length and quality of your life.
The Osteoporosis Reversal Program is the guide that provides the deep knowledge and the simple steps to accomplish those goals. From exercise and nutrition to lifestyle choices, the ORP offers multiple entry points on your journey– without the risks of drug side effects or the narrow focus of some deprivation-based wellness plans.
By taking a wider view of your health, you make it possible to advance multiple goals at once by cross-supporting body systems that depend on each other to thrive.
Stronger Bones. Without Drugs. Guaranteed!
The natural and evidence-based program that helps reverse osteoporosis and osteopenia in 12, 6, even 3 months… guaranteed.
References
1 https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2020.00058/full
3 https://journals.physiology.org/doi/full/10.1152/physrev.00036.2016
Hi Vivian, Wondering if you know anything about “Fosteum Plus,” a “medical food.” I have an osteoporosis diagnosis and do not take any of the drugs. I have been following SaveOurBones for several years. During my annual check up today, my dr. recommended this (Capsule form) as a non-drug option. Do you know anything about this? Is it safe?
I have what I believe to be a healthy immune system, but have osteoporosis. Maybe I don’t. How can one determine whether or not they do?
Hi Jeff,
Having osteoporosis doesn’t necessarily mean your immune system is unhealthy, but the two are closely connected. Immune health isn’t something you can reliably assess based on how you feel alone.
To get a clearer picture, doctors can look at objective markers such as white blood cell counts, inflammation markers like CRP, and immunoglobulin levels, along with clinical clues such as how often you get infections or how well you heal. A healthcare provider can interpret these results in context.
It’s also important to remember that even subtle, chronic immune activation or inflammation, which is often influenced by diet, gut health, stress, and hormones, can affect bone remodeling over time, even when the immune system appears “normal.”
Thank you, Vivian!
You’re welcome, Ruth!
Thanks so much for the above information. I
Unrelated, I notice much comment concerning bananas cutting absorption of flavanols. As this is more likely linked to the heart and brain, would there be a connection to bones? Thanks, Sandra
You’re welcome, Sandra!
And to answer your question, bananas contain an enzyme called polyphenol oxidase (PPO), which can reduce flavanol levels—especially when bananas are blended into smoothies. A 2023 study found that this effect increases as bananas ripen. While flavanols are best known for supporting heart and brain health, they also benefit bones by helping reduce inflammation and oxidative stress and by supporting bone-forming cells. So yes, in theory, reducing flavanol intake could have implications for bone health as well.