Researchers at Wake Forest University School of Medicine are offering cautious optimism: a specialized diet may help protect against Alzheimer’s disease, a condition that primarily affects memory and thinking.
Alzheimer’s is more than occasional forgetfulness, such as misplacing keys or forgetting names. It progressively damages memory and cognitive abilities, making everyday life increasingly difficult.
According to the Alzheimer’s Association, more than 6.5 million Americans are currently living with Alzheimer’s disease. Many older adults ultimately die from Alzheimer’s or related forms of dementia, underscoring the urgent need for effective prevention strategies.
One dietary approach attracting attention is the ketogenic, or “keto,” diet. This eating pattern is high in fats, moderate in protein, and very low in carbohydrates. When carbohydrate intake is restricted, the body switches to using ketones—molecules produced from fat—as its primary source of energy.
In this study, researchers combined the keto diet with elements of the Mediterranean diet. This hybrid approach emphasizes foods such as fruits, vegetables, fish, and olive oil, which are staples in Mediterranean regions including Greece and Italy.
The research team enrolled 20 adults in the study. Some participants had mild memory problems without a diagnosis of Alzheimer’s disease, while others showed no signs of cognitive impairment. Participants were divided into two groups.
One group followed the Mediterranean-style ketogenic diet, while the other consumed a low-fat, high-carbohydrate diet. Each diet was followed for six weeks, separated by a washout period, after which participants switched to the alternate diet.
To explore how diet might influence brain health, the researchers examined changes in gut bacteria by analyzing stool samples collected from participants.
The results showed that the Mediterranean ketogenic diet altered gut bacteria in participants with memory impairment. These changes may have implications for brain health.
For example, after following the Mediterranean ketogenic diet, participants showed lower levels of gut bacteria that produce gamma-aminobutyric acid (GABA), a neurotransmitter involved in brain signaling. Abnormally low GABA activity has been linked to Alzheimer’s disease. At the same time, the diet appeared to increase bacteria involved in regulating GABA balance.
The study also found that when participants consumed curcumin—a compound found in turmeric—their gut microbiota contained fewer bacteria involved in bile acid metabolism, substances the body produces to help digest fats.
Overall, the findings suggest that a Mediterranean-style ketogenic diet, along with certain dietary compounds such as curcumin, may influence gut bacteria in ways that support brain health. However, the researchers emphasize that further studies are needed to confirm these effects.
Experts at Wake Forest University remain hopeful that this research could open new avenues for preventing or potentially treating Alzheimer’s disease. They plan to continue investigating the complex connections between diet, gut microbiota, and brain function.
Maintaining a healthy diet may be one important component of preserving cognitive health. Other studies have linked high blood pressure and vitamin B12 deficiency to increased risks of cognitive decline. Additional research suggests that foods such as cranberries, along with healthy lifestyle habits, may help protect against Alzheimer’s disease.
Full details of the study are published in the journal Alzheimer’s & Dementia.
