22/05/2025
How Kefir Helps Prevent and Slow Alzheimer's Disease
A study examined kefir's potential as a complementary treatment for Alzheimer's disease. The review included seven studies spanning invertebrates, rodents, and humans, and focused on kefir's antioxidant, anti-inflammatory, and neuroprotective properties. Here's what the findings revealed:
• Kefir reduced amyloid plaques and tau tangles — The researchers observed that kefir lowered the accumulation of beta-amyloid proteins, a proposed hallmark of Alzheimer's disease (although recent scientific retractions over data manipulation have raised questions about the impact of this protein). Reductions in tau proteins were also noted. Both of these proteins are believed to be involved in the cognitive decline and neuronal death that occurs in Alzheimer's.
• Cognitive function improved across species — Improvements in memory and behavior were seen in rodents, while fruit fly models demonstrated increased survival and enhanced motor coordination. Kefir supplementation led to a 28% improvement in global cognition and a 66% increase in immediate memory performance, with delayed memory improving by 62%.
• Kefir lowered oxidative stress and preserved neurons — Markers of oxidative damage, like ROS, nitrotyrosine, and iNOS, were reduced after kefir treatment in rodents. Neurons in regions such as the hippocampus and cortex were also better preserved.
• Inflammation and neuronal damage decreased — Kefir reduced inflammatory markers such as NF-κB and caspase-3, which are linked to neuronal apoptosis. It also suppressed key inflammatory pathways (TLR4, MYD88, NLRP3) and reduced proinflammatory cytokines (TNF-α, IL-8, IL-12).
• Immune balance and gut health improved — Studies showed kefir modulated immune responses and restored intestinal mucosal integrity.
• Kefir enhanced insulin signaling in the brain — Some rodent models showed increased levels of insulin-degrading enzyme (IDE) in the hippocampus and better regulation of insulin receptors. These changes support neuron function and reduce amyloid buildup.
• Kefir's unique bioactive compounds drive effects — Kefir contains peptides that block acetylcholinesterase (the same mechanism used by many AD drugs) and reduce oxidative protein damage. Kefiran, a complex carbohydrate found in kefir, also modulates inflammation and gut microbiota. These features make it a promising neuroprotective agent.
• Long-term use may sustain cognitive protection — Beyond short-term studies, kefir's ability to regulate neurotransmitters (dopamine, serotonin, acetylcholine, and GABA) and promote brain-derived neurotrophic factor (BDNF) suggests ongoing benefits with continuous use.
Kefir Supplementation Improves Alzheimer's Symptoms
One of the studies included in the featured review is a clinical trial published in Oxidative Medicine and Cellular Longevity,7 which evaluated the effects of 90 days of kefir-fermented milk on elderly patients with Alzheimer's disease. This trial offered detailed insight into how kefir impacts the core drivers of neurodegeneration.
• Inflammation dropped sharply — Serum levels of proinflammatory cytokines decreased significantly following kefir supplementation. Cytokine ratios also improved, which indicates a shift from proinflammatory to more balanced immune response, which reduces amyloid buildup and protects against brain tissue loss.
• Oxidative stress was suppressed — Levels of superoxide, hydrogen peroxide, and peroxynitrite decreased by 30%, while nitric oxide bioavailability increased by 100%. This improves blood flow and protects neurons from oxidative damage.
• Apoptosis and DNA damage were reversed — DNA fragmentation dropped from 15% to 5%, and cleaved PARP-1 (a marker of programmed cell death) decreased by over 75%. The rate of apoptotic cells (cells that are naturally dying off) dropped by nearly half, while healthy cell populations rose, reflecting improved tissue stability. These changes suggest that kefir not only slows cellular damage but also promotes repair and survival at the tissue level.
• p53 signaling was activated — The expression of p53 tripled following supplementation. This master regulatory protein is essential for DNA repair, mitochondrial protection, and tumor suppression, and its activation helps explain kefir's broad neuroprotective impact.
• A complex synbiotic effect — The kefir used in the study included both beneficial bacteria and yeast species. Its bioactive compounds, such as peptides, polysaccharides, and vitamins, worked together to modulate the gut-brain axis, enhance antioxidant capacity, and trigger neuroprotective pathways like GABA and BDNF.
• Safe and accessible — Kefir was well-tolerated, with no adverse effects reported. While this was an uncontrolled trial, the strength of the biological changes observed justifies future randomized studies and supports kefir's use as a natural, low-risk intervention in early Alzheimer's care.
So…I’ll be buying my milk kefir this afternoon from Hollinshead Dairy 🐄 🥛 in the Nantwich Market. It’s just like the kefir we used to make at home (which in my opinion is way better than the kefir in the supermarkets). If you can’t get to Nantwich try making your own kefir (ideally from raw milk), it’s very easy, you just need to buy the kefir grains and you’re away (see the instructional video on our website).
Be well,
Dr Steve
https://www.sciencedirect.com/science/article/pii/S2949834125000133
https://pmc.ncbi.nlm.nih.gov/articles/PMC7201593/
