Ketogenic Diet and Management of Alzheimer’s Disease: A Literature Review
Abstract
Alzheimer’s Disease (AD) has impacted lives globally, especially in the aging society. The lack of an effective treatment strategy creates a suggestion for dietary practices that can revert the disease’s effects. The ketogenic diet has high fat and low carbohydrate and has shown promising results in managing AD. The presence of ketone bodies has an impact on the aging brain cells. They provide an alternative energy source and reduce the expression of inflammatory mediators. Since the diet has low carbohydrates, it induces physiological ketosis, rendering fats the body’s primary energy source. Ketogenesis leads to the production of ketone bodies which forms the new energy source. The high levels of ketone bodies and the low blood glucose concentration are critical for the therapeutic effects of the Ketogenic Diet (KD). The duration of the intervention determines the success of the intervention. Ketogenesis has several effects, but they are manageable, and patients acclimate to the diet with time. This review aims at studying the role of the ketogenic diet in AD’s progression.
Introduction
The medical benefits of the ketogenic diet have been demonstrated for years. The ketogenic diet is a metabolic shift that stimulates the liver oxidation of fatty acids to produce ketone bodies. The diet became popular in the 1920s and 30s when it was used to treat epilepsy. The diet was an alternative to non-mainstream fasting and demonstrated huge success for years. However, it was later abandoned after the introduction of other powerful therapies. The practice of fasting in treating diseases has been known to mankind for thousands of years. Humankind has been known to cure various diseases as a result of abstaining from consuming various foods or drinks.
Alzheimer’s disease has been the leading cause of dementia, especially in aging societies. The various medications developed to fight Alzheimer’s(AZ) have not been effective. Therefore, dietary modifications and other therapies practices have been reviewed to assess their effectiveness in fighting AZ. Some studies linked omega-3 fatty acids, vitamins B and E with the prevention and management of AZ. However, sufficient evidence is lacking, and therefore the treatment procedures cannot be recommended. Dietary patterns such as the Mediterranean have been tried in the treatment and management of AZ. A ketogenic diet has received increasing interest in the management of AZ.
The topic of the Ketogenic Diet and Management of Alzheimer’s Diseases is important since it impacts the aging population. A successful study on the subject can provide a potential management therapy for AD and promote the health of the elderly. AD affects people’s health and reduces the quality of life at an advanced age. Therefore, a treatment or a management plan will be pivotal in improving their mortality rate. The review is very important and relevant since it will improve my understanding of what has been discovered by past researchers. Previous studies will offer a good background and understanding to direct the current study. These researchers will indicate the limitations, which will help avoid replicating the errors in the current research. Additionally, the review will uncover gaps and set the direction for future studies. From the studies, I want to find out and learn about the impact of a ketogenic diet on AD patients and its applicability in society. The articles used in the review are peer-reviewed and published from 2019 onwards. This is to ensure that the information captured is current and reliable. The review examines the role of the ketogenic diet as a drug therapy for Alzheimer’s disease.
Analysis
Alzheimer’s disease
AD is a common disease among the aging population. Its patients suffer from memory loss and have impaired cognitive functions. More than 47 million people live with dementia across the world (Xu et al. 2022). AD results from the accumulation of Aβ and extensive loss of neurons and synapses. Patients suffering from AD have low levels of brain insulin, which inhibits them from functioning correctly (Phillips et al. 2021). There have been several clinical therapies that have aimed at reducing Aβ. However, these therapies have had disappointing results creating the need for a new therapy structure.
Ketogenic diet
A study conducted by (Xu et al.2022; Phillips et al.2021) revealed how a ketogenic diet improved cognitive functions. The mice used in the study depicted a reversed synapse and neuronal loss. The diet was effective in decreasing microgliosis and reducing neurotoxic. Synaptic transmission is very costly, and it is possible that age-related impairments in cerebral glucose metabolism decline with age. However, utilizing ketone bodies for energy production does not decline with age, forming a sound basis for prevention and management strategies. Ketone diets have high-fat content, are low in carbohydrates and thus easily switch primary fuel sources from glucose to ketone bodies. `
Emerging studies depict that the microbiome composition plays a crucial role in human health, especially cognitive performance. The diagnosis of AD using molecular makers is not reliable, which creates room for a better investigative tool. According to Nagpal et al. (2019), the investigation of the novel biomarkers can provide an efficient diagnosis and prognosis of AD. The gut microbiome plays a crucial role in brain function and pathology, making them suitable for AD biomarkers. The diet that people take plays a role in determining their immune system. It can influence the features of host metabolism and immune function (Nagpal et al. 2019). Specific gut microbiome signatures and organic acids can function as biomarkers for the spectrum of AD pathology and thus would provide a prospective intervention and clinical studies exploring novel nutrition. Improvements in these interventions would be helpful for accurate medicine approaches against Alzheimer’s risk and dementia.
KD is a biochemical model of fasting. In food deprivation, the brain uses other alternative energy sources, which include ketone bodies. Patients who are under the ketogenic diet have depicted improved cognitive health. The degree of improvement is considerably high than what is observed with other medical treatments. The quality of life for people with AD and under a ketogenic diet has been reported to increase (Phillips et al. 2021; Xu et al.2022; Nagpal et al. 2019). However, it is not clear whether ketogenic offers benefits regarding cardiovascular risk factors. Experts have concerns about the suitability of the ketogenic diet for patients. Patients on a ketogenic diet experienced a massive weight loss. However, there is a controversy with a group of experts stating that the weight loss might be due to appetite changes in the later stage of the disease (Phillips et al. 2021). Weight loss among AD patients increases their mortality rate.
Side effects of the Ketogenic Diet
A ketogenic diet has been associated with mild to adverse effects on patients. Patients under ketogenic treatment experience increased irritability. One experiences carbohydrates withdrawal after starting a ketogenic diet. Patients experience brain fog which occurs due to the body reacting to the change in energy source. The lowered insulin levels cause a diuretic effect and other electrolyte abnormalities. The lack of sodium and potassium may cause muscle cramps in the legs and the back. However, these conditions are easy to manage. Patients can adopt eating more salt and drinking water. The effects are short-lived, as depicted in the study, where patients show adverse effects at week six and mild effects by week 12 (Phillips et al. 2021). Therefore, the side effects of the diet decline as the patients become acclimated to the new food.
Time for Intervention
Time for ketogenic diet intervention plays a crucial role in preventing and managing AD. According to Xu et al. (2022) study, amyloid plague is detected at two months, synapse loss and cognitive impairment at six months, and neuronal loss at one year. Therefore, when a treatment plan is slotted at the correct interval, the patient has increased chances of living a better life. A ketogenic diet initiated at seven months may improve cognitive functions during the fourth month. Therefore, applying a ketogenic diet at the early stages of AD can have potent therapeutic effects. Intervention initiated the nine months since diagnosis shows no beneficial effect. The time for intervention depends on the condition of the patients. Studies affirm that shorter intervention has noticeable improvements than more extended intervention (Xu et al. 2022; Nagpal et al. 2019; Phillips et al.2021). However, these improvements are weak and short-lived. Therefore, patients should stick to the long-term intervention for better results. Medical caregivers should thoroughly scan the patients to determine the best intervention to yield better results.
Conclusion
The use of KD has been growing extensively in the treatment of diseases. Conditions such as diminished mitochondrial associated with brain energy and changes in the neurotransmitter are key conditions observed among AD patients. Animal studies and clinical trials have shown that the ketogenic diet improves the conditions of Alzheimer’s disease patients. The improvement outcome depends on the ketogenic diet intervention’s level and duration. Improved outcomes are experienced in short-term intervention, although they are short-lived. A practical diagnostic approach can yield the best result if the KD treatment is adopted in the early presymptomatic stages of Alzheimer’s. Future research should focus on identifying the exact action of KD and how it restores energy metabolism. Additionally, the studies should explore the long-term effects of KD on AD’s progress in patients.
References
Nagpal, R., Neth, B. J., Wang, S., Craft, S., & Yadav, H. (2019). Modified Mediterranean-ketogenic diet modulates gut microbiome and short-chain fatty acids in association with Alzheimer’s disease markers in subjects with mild cognitive impairment. EBioMedicine, 47, 529-542.
Phillips, M. C., Deprez, L. M., Mortimer, G., Murtagh, D. K., McCoy, S., Mylchreest, R., … & Schepel, J. A. (2021). Randomized crossover trial of a modified ketogenic diet in Alzheimer’s disease. Alzheimer’s research & therapy, 13(1), 1-12.
Xu, Y., Jiang, C., Wu, J., Liu, P., Deng, X., Zhang, Y., … & Zhu, Y. (2022). Ketogenic diet ameliorates cognitive impairment and neuroinflammation in a mouse model of Alzheimer’s disease. CNS neuroscience & therapeutics, 28(4), 580-592.
