Doctors and scientists are not giving up on the quest to find a cure for Alzheimer’s disease. Though it was announced this week that one potential drug failed in clinical trials, another experimental drug was reported to decrease Alzheimer’s risk by 50 percent in high-risk patients. Other research is also looking at how lifestyle factors may be able to treat the disease. Take, for example, a systematic review published this week that suggests consuming kefir can improve Alzheimer’s symptoms.
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What is kefir?
Kefir is a cultured milk drink. It's similar to but thinner than yogurt, and it has a more tangy taste. As Best Life previously explained, it's "made by melding dairy milk with kefir grains, a mixture of bacteria and yeast that contain lactic acid bacteria, yeast, and acetic acid bacteria."
The beverage is low in lactose but high in gut-healthy probiotics, protein, calcium, and B vitamins, according to Mayo Clinic.
Kefir is popular in Eastern Europe and Russia, but it's still a bit of an underrated superfood here in the U.S. It can be drunk plain, added to smoothies, eaten with cereal, and more.
What is the connection between kefir and Alzheimer’s?
For the recent systematic review, published in the journal Brain Behavior and Immunity Integrative, researchers examined the results of seven studies, including one involving human participants, that looked at the relationship between kefir and neurodegenerative diseases.
Based on animal studies, the researchers determined that kefir had the following positive effects:
- Reduced beta-amyloid deposition (a plaque-like buildup that occurs in the brain and is associated with Alzheimer's disease)
- Reduction of vascular damage and neurodegeneration
Based on human trials, they saw the following:
- Improved memory
- Decreased levels of inflammatory cytokines (proteins that promote inflammation, which is known to worsen Alzheimer's)
- Decreased levels of reactive oxygen species (which can lead to oxidative stress and promote disease)
- Decreased levels of oxidative proteins (proteins that have been modified from their original form and are associated with Alzheimer's and Parkinson's disease)
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Why does kefir have these positive effects?
Simply put, the positive relationship between kefir and neurodegenerative health all comes down to the beverage's probiotics—which affect gut health and, therefore, the gut-brain connection.
"Gut microbes produce or help produce many of the chemical neurotransmitters that convey messages between your gut and brain," explains Cleveland Clinic. "They also produce other chemicals that can affect your brain through your bloodstream."
As Best Life previously noted, kefir "contains around 60 species of 25-30 billion colony-forming units (CFUs) of gut-healthy probiotics." To put this in perspective, the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) says that "many probiotic supplements contain 1 to 10 billion CFU per dose."
Moreover, nutritionistBharathi Ramesh explained that, "unlike yogurt, kefir typically contains a wider range of strains, which can have a more comprehensive impact on your gut microbiome."
So, how does this all tie together?
"Kefir may support brain health by helping to restore a balanced gut microbiome, reducing systemic inflammation, and strengthening the gut barrier, which can limit neuroinflammation," Peter Gliebus, MD, director of cognitive and behavioral neurology at Marcus Neuroscience Institute (who was not involved in the study), explained to MedicalNewsToday.
"[Kefir’s] bioactive compounds have antioxidant properties that could potentially protect neurons from oxidative stress," he continued. "This protection can help preserve synaptic and mitochondrial function, potentially slowing down neurodegeneration."
However, the study authors and Gliebus agree that more research in humans about kefir's relationship with Alzheimer's disease is necessary.
The takeaway:
How often should I consume kefir?
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A new review of seven studies suggests that kefir, a cultured milk drink, could help prevent or treat Alzheimer's disease due to its high concentration of probiotics that have a positive effect on the gut-brain connection. However, more research is needed in humans.
