This study investigates how diet, particularly its inflammatory potential, influences the risk of developing dementia, including Alzheimer’s disease (AD). Dementia is a growing global concern, predicted to affect 152 million people by 2050. While significant efforts have gone into treating dementia and improving patient care, less progress has been made in preventing the disease. Diet, a modifiable factor, shows promise in reducing the risk of dementia, particularly through anti-inflammatory dietary patterns.
The Dietary Inflammatory Index (DII) measures the inflammatory potential of a person’s diet based on specific nutrients and foods. Foods with high DII scores are considered pro-inflammatory, meaning they can increase levels of inflammation in the body. Conversely, foods with low or negative DII scores are anti-inflammatory, reducing inflammation.
The following food groups have high pro-inflammatory properties:
• Saturated fats (found in fried foods, butter, and red meat)
• Trans fats (often in processed snacks)
• Added sugars and refined carbohydrates (like white bread, pastries, and sugary beverages)
• Excess protein and cholesterol from unhealthy sources
Foods with anti-inflammatory properties are your whole foods consisting of:
• Fruits (like berries and citrus fruits)
• Vegetables (especially leafy greens like spinach and kale)
• Nuts and seeds (such as almonds, walnuts, and flaxseeds)
• Whole grains (like oats and brown rice)
• Healthy fats (like olive oil and fatty fish high in omega-3s)
• Spices (like turmeric and ginger)
Dementia involves chronic brain inflammation, which contributes to nerve damage, reduced brain volume, and cognitive decline. Pro-inflammatory diets may worsen this inflammation, increasing the risk of dementia. On the other hand, anti-inflammatory diets help regulate inflammation, potentially protecting the brain from damage.
The study used data from the Framingham Heart Study (FHS) to explore the relationship between diet and dementia risk. Researchers followed 1,487 participants over 22 years, assessing their diets using a validated food questionnaire and calculating their DII scores. They found a clear link: individuals with higher (pro-inflammatory) DII scores were significantly more likely to develop all-cause dementia and AD.
Participants with diets rich in pro-inflammatory foods were at greater risk for developing dementia. For instance, those in the highest DII quartile (most pro-inflammatory diets) had an 84% higher risk of developing dementia compared to those in the lowest quartile (most anti-inflammatory diets).
These findings align with previous studies showing that pro-inflammatory diets are linked to cognitive decline and dementia. For example, studies have shown that Mediterranean and MIND diets, which are anti-inflammatory, reduce dementia risk.
Chronic inflammation caused by diet leads to the production of harmful molecules, which can damage brain cells such as the formation of amyloid plaques, a hallmark of AD.
The study suggests that dietary interventions could be a powerful tool for reducing dementia risk. Public health guidelines could emphasize anti-inflammatory diets, incorporating foods rich in nutrients like omega-3 fatty acids, vitamins, and antioxidants. Simple dietary swaps—like replacing red meat with fish or adding more fruits and vegetables—can make a significant difference.
While the findings are compelling, the study has limitations: The data comes from a mostly White population, so findings may not apply to all ethnicities. The observational nature of the study means it cannot prove causation, only an association. Also, the dietary data relies on self-reports, which can be subject to recall bias on the part of the participants.
Conclusion
This research highlights the importance of diet in preventing dementia. Pro-inflammatory diets increase the risk of all-cause and AD dementia, while anti-inflammatory diets offer protective benefits. By choosing anti-inflammatory foods and reducing the intake of processed and high-fat items, individuals may lower their risk of developing dementia. Future studies across diverse populations will be essential to confirm these findings and guide global dietary recommendations.