Can Kefir Support Bone Healing, Skeletal Health, and Reduce Inflammation?
Current research suggests promising results. Some of kefir's potential benefits have been demonstrated in clinical studies involving humans, while others have so far been observed primarily in preclinical research.
1. Accelerated Bone Fracture Healing
Preclinical studies suggest that peptides derived from kefir may significantly accelerate the healing of bone fractures. A study published in
Life Sciences (2022) found that treatment with kefir-derived peptides improved the bone fracture healing process [1].
These peptides appear to stimulate the formation of new bone cells and increase the expression of key factors involved in bone regeneration.
The researchers concluded that kefir-derived peptides may serve as a promising nutritional supplement to support bone healing following fractures.
2. Improved Bone Mass in Postmenopausal Osteoporosis
Osteoporosis is a major health concern, particularly among postmenopausal women, due to the decline in estrogen levels. Several studies suggest that kefir may have beneficial effects on bone mass and bone microarchitecture in postmenopausal osteoporosis [2] [3].
In a randomized clinical trial involving 40 patients with osteoporosis, researchers found that consuming kefir-fermented milk supplemented with calcium for six months resulted in a greater increase in bone mineral density (BMD) compared with calcium supplementation alone [2].
However, the clinical trial included a relatively small number of participants. Larger, well-designed studies are still needed to confirm these findings and determine the long-term effects of kefir on bone health.
3. Preventing Bone Loss Associated with Estrogen Deficiency
Estrogen deficiency is the primary cause of bone loss following menopause. A 2020 scientific study found that kefir-derived peptides helped prevent bone loss associated with estrogen deficiency in a preclinical model [4].
Interestingly, kefir-derived peptides also appeared to have beneficial effects on the gut microbiota, which may further support bone health through the gut–bone axis.
4. Reducing Inflammation and Bone Loss in Periodontitis
Periodontitis is a chronic inflammatory disease that affects the tissues supporting the teeth and can lead to the loss of alveolar bone, the bone that anchors the teeth in place. Preclinical research suggests that kefir may also have beneficial effects in this condition.
A study published in
Biomedicine & Pharmacotherapy (2021) found that
treatment with milk kefir reduced inflammation and alveolar bone loss in a preclinical model of periodontitis [5]. These effects are thought to result from kefir's anti-inflammatory and antiresorptive properties, which help limit the breakdown of bone tissue.
5. Rheumatoid Arthritis – Reduction of Inflammation
Rheumatoid arthritis is a chronic autoimmune disease characterized by joint inflammation (synovitis), bone erosion, and damage to joint structures. In this condition, kefir-derived peptides have also shown promising anti-inflammatory effects in preclinical research.
A recent study from 2023 investigated the therapeutic effects of kefir-derived peptides on arthritis [6]. The results showed that treatment with kefir peptides reduced the severity of inflammation (synovitis) and bone erosion in joints. Kefir-derived peptides were found to inhibit the production of pro-inflammatory cytokines triggered by IL-1β and reduce the expression of matrix metalloproteinases (MMPs), enzymes involved in cartilage degradation.
The researchers concluded that kefir-derived peptides exhibit significant anti-inflammatory properties and represent a promising area for further investigation in rheumatoid arthritis research.
Kefir should not be considered a replacement for medical treatment of osteoporosis, rheumatoid arthritis, or other diseases. However, it may be included as part of a balanced diet and a healthy lifestyle.
6. Kefir, the Gut Microbiome, and Bone Health
An increasing number of studies highlight a crucial connection between the gut, the immune system, inflammation, and bone metabolism. This so-called “gut–bone axis” helps explain how the microorganisms in our intestines can directly influence skeletal health. It represents an important intersection of four key aspects of holistic health: the microbiome, stress, inflammation, and longevity.
Kefir, rich in probiotics and bioactive peptides, has been shown to positively influence the composition of the gut microbiome. Scientific studies indicate that
a healthy gut microbiota produces short-chain fatty acids (SCFAs). These fatty acids play an important role because they help reduce inflammation in the body, strengthen the intestinal barrier, and directly inhibit the formation and activity of osteoclasts — cells responsible for breaking down bone tissue [7,8].
Furthermore, chronic stress increases cortisol levels, which can disrupt the balance of the gut microbiome and contribute to systemic inflammation — a process associated with accelerated bone loss and aging.
Through its beneficial effects on the microbiome, kefir may help regulate inflammatory responses and support immune system balance [4,8]. Regular kefir consumption may therefore support not only digestive health but also, through the reduction of inflammation and oxidative stress, contribute to maintaining stronger bones and healthy aging.
Summary
Current scientific research suggests that kefir, due to its probiotics and bioactive peptides, may be a promising food for supporting bone health and regulating inflammatory processes. The strongest evidence in humans currently relates to its potential beneficial effects on bone metabolism in osteoporosis, while the effects on fracture healing, periodontitis, and arthritis have so far been demonstrated mainly in preclinical studies.
Although the research findings are promising, larger and long-term clinical studies are still needed to better define the impact of kefir on bone health, joint health, and immune system function.
Nevertheless, regular consumption of high-quality kefir may be a valuable part of a balanced diet that supports gut health, bone health, and overall well-being.
Sources and References
[1] Lai, J. C., et al. (2022). Kefir peptides promote osteogenic differentiation to enhance bone fracture healing in rats. Life Sciences, 310, 121090.
[2] Tu, M. Y., et al. (2015). Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients. PLoS One, 10(12), e0144231.
[3] Chen, H. L., et al. (2015). Kefir improves bone mass and microarchitecture in an ovariectomized rat model of postmenopausal osteoporosis. Osteoporosis International, 26(2), 589–599.
[4] Tu, M. Y., et al. (2020). Kefir Peptides Prevent Estrogen Deficiency-Induced Bone Loss and Modulate the Structure of the Gut Microbiota in Ovariectomized Mice. Nutrients, 12(11), 3432.
[5] Vieira, L. V., et al. (2021). Milk Kefir therapy reduces inflammation and alveolar bone loss on periodontitis in rats. Biomedicine & Pharmacotherapy, 139, 111677.
[6] Chuang, K. C., et al. (2023). Therapeutic effects of kefir peptides on adjuvant-induced arthritis in rats through anti-inflammation and downregulation of matrix metalloproteinases. Life Sciences, 317, 121411.
[7] Zaiss, M. M., et al. (2019). The gut-bone axis: how bacterial metabolites bridge the distance. The Journal of Clinical Investigation, 129(8), 3018–3028.
[8] Feng, B., et al. (2024). The role of short-chain fatty acids in the regulation of osteoporosis: new perspectives from gut microbiota to bone health: A review. Medicine, 103(34), e39471.