The number of people with Alzheimer’s disease and other types of dementia is expected to triple by 2050, prompting researchers to seek new ways of preventing and treating the condition. A study conducted by researchers at the University of California, Davis found that following a ketogenic (keto) diet may significantly decrease blood levels of tau protein in a rat model of Alzheimer’s disease. The keto diet also helped decrease blood lipid levels in the animal model. This study focused on improving cognitive behavior, motor function, and blood lipids, which can all play a role in the development of Alzheimer’s disease.
Previous studies have linked high levels of cholesterol to an increased risk for Alzheimer’s disease. The researchers in this study sought to determine how different types of keto diets – continuous or intermittent – may impact Alzheimer’s disease in a rat model. The continuous ketogenic diet was designed to produce a continuous elevation in blood ketone levels, while the intermittent ketogenic diet was designed to produce increases in blood ketone levels for only part of each day. The study used a TgF344-AD rat model of Alzheimer’s disease, which produces changes in a wide range of Alzheimer’s disease-related pathologies.
By the age of 12 months, rats on both types of keto diet did not show improved spatial learning memory or motor coordination compared to those on a control diet. However, rats on both types of keto diet experienced decreased cholesterol levels. Additionally, the keto diet significantly decreased blood levels of tau protein in female rats. The researchers noted that a ketogenic diet may be beneficial in slowing or mitigating some aspects of Alzheimer’s disease onset and progression in individuals with genetic susceptibility.
Monique Richard, a registered dietitian nutritionist, emphasized that while the keto diet is effective for specific medical conditions when closely monitored, it may not be suitable for everyone. She warned that the keto diet can be difficult to follow, unsustainable long-term, and could have negative consequences on lipid profiles, liver enzymes, digestive health, cognition, and satisfaction with eating. Richard also pointed out the importance of meeting macro- and micronutrient needs while following the diet to avoid potential health issues.
The researchers suggested that translating the findings of the study to humans would involve consuming a ketogenic diet or ketone supplement before the development of major disease symptoms. Long-term diet studies in humans would be necessary to determine if the diet produces sufficient changes to warrant continued consumption. Future research will focus on determining if the ketogenic diet significantly alters markers of pathology and cellular processes that contribute to Alzheimer’s disease progression. Overall, the study highlights the potential benefits of a ketogenic diet in improving cognitive behavior, motor function, and blood lipid levels in a rat model of Alzheimer’s disease.
