Many observational studies have linked a Mediterranean diet to better cognitive health.
The gold standard eating pattern has been tied to a slower rate of cognitive decline and a lower dementia risk.
It’s also the only dietary pattern demonstrated in a long-term randomized controlled trial to improve cognitive function in older adults.
Now, new research suggests that people at high genetic risk for Alzheimer’s disease may benefit the most by following a Mediterranean diet.
Here’s what to know about the study, plus key Mediterranean diet components to include in your regular menu.
The link between genetics and ‘sporadic’ Alzheimer’s disease
Sporadic Alzheimer’s disease, the most common type, develops later in life and is not directly tied to family history. Rather, it’s due to an interaction between genetics, the environment and lifestyle factors.
apolipoprotein E (APOE) is a gene that’s associated with varying risks of Alzheimer’s disease (AD), depending on the variant of the gene a person has. Each person inherits two copies of the APOE gene,one from their mother and one from their father.
The APOE4 variant is the strongest genetic risk factor for late-onset AD.
People who carry one copy of the variant have a three- to four-fold greater risk of developing AD. People who have two copies have an eight- to 12-fold higher risk compared to those who don’t.
In the brain,APOE4 promotes the accumulation of sticky beta-amyloid plaques,impairs glucose regulation and the removal of cholesterol and fats,and promotes inflammation.
About the new study
For the study, published Aug. 25 in the journal Nature Medicine, researchers investigated whether following a Mediterranean diet could benefit people with varying genetic risk for AD.
The team also looked at how adherence to the diet influenced dementia-related blood metabo
Diet May help Protect Against Cognitive Decline, Especially for Those with Genetic Risk
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A growing body of research suggests that dietary choices play a significant role in maintaining cognitive health and potentially reducing the risk of Alzheimer’s disease (AD) and other forms of dementia. This is notably critically important for individuals carrying the APOE4 gene, which significantly increases their susceptibility to AD. Focusing on specific nutrients found in colorful fruits and vegetables, like betaine and carotenoids, may offer a protective effect.
The Link Between Genetics and Alzheimer’s Disease
The APOE gene has several forms, with APOE4 being the most strongly associated with an increased risk of late-onset alzheimer’s disease. Having one copy of the APOE4 gene increases risk, while carrying two copies – approximately 25% of the population does – dramatically elevates that risk. https://www.nia.nih.gov/health/alzheimers-and-dementia/apoe-gene-and-alzheimers-disease However, genetics aren’t destiny. Lifestyle factors, including diet, can significantly influence whether or not someone develops the disease.
Key Nutrients for Brain Health
Recent research highlights several nutrients that appear to be particularly beneficial for cognitive function, especially in those genetically predisposed to AD:
Betaine: This phytochemical, abundant in beets, spinach, and whole grains, shows promise in protecting the brain. It’s believed to work by removing toxic compounds, improving blood flow, and reducing inflammation and oxidative stress. https://pubmed.ncbi.nlm.nih.gov/37688699/
Carotenoids: These anti-inflammatory compounds are found in red, yellow, orange, and dark green vegetables and fruits (like carrots, sweet potatoes, kale, and bell peppers). Higher intake of carotenoids has been linked to slower cognitive decline, particularly in APOE4 carriers. https://pubmed.ncbi.nlm.nih.gov/28694341/
beyond Specific Nutrients: The Importance of an Anti-Inflammatory Diet
While betaine and carotenoids are receiving attention, the broader picture points to the benefits of an overall anti-inflammatory diet. Chronic inflammation is a key contributor to neurodegenerative diseases like Alzheimer’s. Diets rich in fruits, vegetables, whole grains, lean protein, and healthy fats (like those found in the Mediterranean diet) can definitely help combat inflammation. Conversely, diets high in processed foods, sugar, and saturated fats can exacerbate it. https://www.alz.org/alzheimers-dementia/what-is-dementia/causes-and-risk-factors/diet-and-risk
The Mediterranean Diet and Cognitive Health
The Mediterranean diet, consistently ranked as one of the healthiest dietary patterns globally, is strongly associated with improved cognitive function and a reduced risk of Alzheimer’s disease.This diet emphasizes:
Abundant fruits and vegetables
Whole grains
Legumes
Nuts and seeds
Olive oil as the primary fat source
Moderate consumption of fish and poultry
Limited red meat and processed foods
What Does This Mean for You?
The findings reinforce the idea that a healthy diet isn’t just about physical health; it’s crucial for brain health to.Even for individuals with a genetic predisposition to Alzheimer’s, dietary modifications can potentially delay the onset or slow the progression of cognitive decline.
Key Takeaways:
Diet plays a significant role in cognitive health.
Individuals with the APOE4 gene may benefit particularly from a brain-healthy diet.
Focus on foods rich in betaine and carotenoids.
Adopt an anti-inflammatory dietary pattern,such as the Mediterranean diet.
Looking Ahead: Ongoing research continues to explore the complex relationship between diet, genetics, and brain health. future studies will likely identify even more specific nutrients and dietary patterns that can help protect against cognitive decline and dementia.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on X* https://twitter.com/LeslieBeckRD