Alzheimer’s disease represents not just a memory-stealing ailment but also a considerable challenge for healthcare systems. Researchers are continuously seeking new ways to slow down or potentially halt its progression. In a scientific review published in Frontiers in Neuroscience, a new spotlight has been cast on an unconventional player: the ketogenic diet, a regimen more commonly associated with weight loss and epilepsy management.
Alzheimer’s disease is a progressive neurological disorder primarily affecting the elderly, characterized by memory loss, cognitive decline, and personality changes. It is the most common cause of dementia, a general term for memory loss and other cognitive abilities serious enough to interfere with daily life. Alzheimer’s disease accounts for an estimated 60-70% of dementia cases. The disease progresses in stages, from mild cognitive impairment to severe dementia, drastically affecting the quality of life of patients and their families.
The ketogenic diet is a high-fat, moderate-protein, and low-carbohydrate diet. Traditionally used to treat drug-resistant epilepsy, the diet has recently garnered attention for its potential benefits in other neurological disorders, including Alzheimer’s disease. The diet works by shifting the body’s primary energy source from carbohydrates to fats. This shift leads to the production of ketone bodies, an alternative energy source for the brain, particularly when glucose (the usual energy source) is scarce.
The researchers behind the new review were motivated by the need to explore new therapeutic avenues for Alzheimer’s disease, a condition that continues to pose a significant challenge globally. As the disease’s prevalence and impact grow, especially with aging populations worldwide, there is a pressing need for innovative and effective management strategies.
“I have a longstanding interest in Alzheimer’s disease particularly with respect to early diagnosis, prevention and treatment. There are no effective drugs to improve memory and cognition. This approach is attractive to reduce cognitive decline,” said study author Ralph Martins, a professor of neurobiology at Macquarie University and the director of research at the Australian Alzheimer’s Research Foundation.
The Review: Key Findings and Implications
1. Brain Energy Metabolism and Alzheimer’s Disease: Alzheimer’s disease is marked by a decrease in the brain’s ability to utilize glucose, leading to an energy crisis. The ketogenic diet could address this issue by providing ketone bodies as an alternate fuel source, potentially alleviating energy deficits in the Alzheimer’s-affected brain.
2. Impact on Amyloid Beta and Tau Proteins: The accumulation of amyloid beta and tau proteins in the brain is a hallmark of Alzheimer’s disease. The review highlighted that the ketogenic diet could influence the transport and clearance of amyloid beta across the brain’s protective barrier, potentially reducing plaque deposition and mitigating soluble amyloid beta. Similarly, the diet showed promise in ameliorating abnormal tau aggregation, a critical factor in the formation of neurofibrillary tangles associated with Alzheimer’s disease.
3. Astroglial Markers and Neuroinflammation Astrocytes, star-shaped cells in the brain, play a vital role in the development and progression of Alzheimer’s disease. The ketogenic diet has been found to reduce markers of astrocyte activation and neuroinflammation, suggesting a protective role against the neurodegenerative processes of Alzheimer’s disease.
4. Neurofilament Light Chain: A Marker of Neuronal Damage: The diet also showed potential in reducing levels of neurofilament light chain, a biomarker indicating neuronal damage. This suggests that the diet could have protective effects against the neurodegeneration seen in Alzheimer’s disease.
5. Cognitive Performance Improvements: Various studies have reported improvements in cognitive performance, including memory, executive function, and processing speed in individuals following a ketogenic diet. These improvements were particularly notable in individuals with mild cognitive impairment, a precursor to Alzheimer’s disease.
6. Influence on Neurotrophic, Neuroinflammation, Apoptotic, and Oxidative Stress Factors: The ketogenic diet was found to influence various pathways and markers related to neuroprotection, inflammation, and oxidative stress. It increased levels of brain-derived neurotrophic factor, reduced pro-inflammatory cytokines, and modulated apoptotic pathways, all of which play significant roles in the progression of Alzheimer’s disease.
The scientific review sheds light on the potential of the ketogenic diet as a novel approach to managing Alzheimer’s disease. The findings of the review indicate that medium-chain fatty acids, a key component of the ketogenic diet, can offer an alternative energy source for the brain, particularly in the context of Alzheimer’s disease.
“Energy metabolism in the brain is compromised in Alzheimer’s disease,” Martins told PsyPost. “Medium-chain fatty acids provide an alternate energy source for the brain compensating for the reduced glucose utilization.”
However, the researchers emphasize the need for further research to fully understand the mechanisms and long-term effects of the diet on Alzheimer’s disease progression. While the findings are promising, they are not a green light for everyone to switch to a ketogenic diet just yet. Alzheimer’s disease is complex, and what works for one patient may not work for another. Future research should focus on understanding who could benefit most from this diet, the optimal dietary composition, and how long patients should follow it.
“Nutrition is important for brain health,” Martins said. “Nutritional drinks such as Souvenaid has been shown to slow the progression of mild cognitive impairment to Alzheimer’s disease and adherence to the MIND diet protects the brain against Alzheimer’s. Medium chain fatty acids are excellent candidates for neuroprotection but evidence-based clinical trials are necessary to determine their significance.”
It is essential for individuals interested in the ketogenic diet, especially those with pre-existing health conditions, to consult healthcare professionals before making any significant dietary changes. Tailoring the diet to individual needs and medical conditions is crucial to ensuring safety and effectiveness.
The paper, “Ketone bodies mediate alterations in brain energy metabolism and biomarkers of Alzheimer’s disease“, was authored by Matin Ramezani, Malika Fernando, Shaun Eslick, Prita R. Asih, Sina Shadfar, Ekanayaka M. S. Bandara, Heidi Hillebrandt, Silochna Meghwar, Maryam Shahriari, Pratishtha Chatterjee, Rohith Thota, Cintia B. Dias, Manohar L. Garg, and Ralph N. Martins.
