Anti-Inflammatory Diet Associated with Reduced Risk of Dementia-Related Diseases

by | Feb 14, 2022 | 2021, Brain Health, Cognitive Health

Written by Taylor Woosley, Staff Writer. Study results suggest that the inclusion of an anti-inflammatory diet may offer significant protection against neurodegenerative disorders, with participants in the highest pro-inflammatory diet group having a 3 times higher chance of developing dementia.

plate of vegetables and riceHuman life expectancy has dramatically increased over the last 200 years, with population aging accelerating from 461 million people 65 years and older in 2004 to an estimated 2 billion people by 2050 1. This dramatic rise in aging populations can be attributed to a variety of factors, such as improved food and water quality, advanced hygiene practices, and increasingly enhanced medical care 2. Advanced aging is a major risk factor for prevalent chronic diseases, with the aging process consisting of genomic damage, mitochondrial dysfunction, and cellular senescence 3. Cellular senescence occurs as the result of chronic stressors, causing senescent cells to accumulate as we age, promoting a variety of age-related diseases 4.

Additionally, during aging, chronic, low-grade inflammation develops, which further accelerates the aging process and contributes to age-related diseases 5. Inflammation is how the body responds to tissue damage and the inflammatory response causes cellular changes 6. However, if inflammation remains chronic, these cellular changes may result in cell mutations and proliferation. One hallmark of the aging nervous system is cognitive decline, which is characterized by the deterioration of mental capacity and the eventual development of neurodegenerative diseases 7. Dementia, a neurodegenerative disorder linked to chronic inflammation, affects over 50 million people worldwide and that number is projected to triple by 2050 8. Dementia and Alzheimer’s disease (the most common cause of dementia) are the fifth-leading cause of disability and death among individuals 60 years and older globally 9. Although treatment of dementia-related disorders still needs to be better understood, addressing modifiable risk factors such as diet can play a significant role in reducing the likelihood of developing this pro-inflammatory neurodegenerative disorder. The inclusion of nutrient dense whole foods containing robust polyphenols, unsaturated fats, antioxidants, and vitamins may inhibit oxidative stress, thus reducing the risk of neuroinflammation.

In this study, Charisis et al explored the potential role an anti-inflammatory diet may play to reduce the occurrence of dementia-related cognitive disorders. A total of 1059 individuals (mean age=73.1 years; 40.3% males; mean education=8.2 years) were recruited for this cohort study. Participants were selected through random population sampling and followed for a mean of 3.05 years. Inclusion criteria consisted of completing a food frequency questionnaire (FFQ), reporting daily energy intake, and experiencing no baseline dementia. The food frequency questionnaire was assessed through the Diet Inflammatory Index (DII) score, which considers associations of 45 food parameters with levels of either pro- or anti-inflammatory cytokines in the blood. The higher the score’s value, the higher the level of inflammatory components existing in the diet. To better explore the exposure-disease relationship of the inflammatory diet potential, the DII scores were grouped into the tertiles shown below:

1 st tertileMaximal anti-inflammatory diet potential
2 nd tertileIntermediate pro-inflammatory diet potential
3 rd terileMaximal pro-inflammatory diet potential

After a 3-year follow-up, the results were as follows:

  • Greater inflammatory diet potential was associated with a significantly higher risk for dementia. Specifically, there was a 21% increase in the risk of dementia with each additional unit of DII [HR=1.21 (1.03 – 1.42); p=0.023].
  • Compared to participants in the lower DII tertile (anti-inflammatory diet), participants in the highest tertile were 3 [(1.2 – 7.3); p=0.014] times more likely to develop dementia.
  • When comparing acceptable energy reporters, a higher proportion of participants with acceptable energy levels reported were men [n (%) = 347 (43) vs. 80 (33); p=0.006].
  • The significant test for trend indicated a potential dose-response relationship (ptrend=0.017).

In conclusion, results of the study show that higher DII scores (pro-inflammatory diet) are associated with an increase in the risk of dementia. These findings suggest the importance of using nutrient dense foods that are naturally anti-inflammatory as a potential preventative measure against neurodegenerative diseases. Study limitations include a significant loss of follow-up participants (n=689), potential of disease misclassification due to dementia diagnoses being based solely on clinical criteria, and the potential possibility of reverse causality due to the short follow-up of the study (mean=3.05 years). Further research should be conducted to better understand the role food and lifestyle play as preventive measures against dementia-related diseases.

Source: Charisis, Sokratis, Eva Ntanasi, Mary Yannakoulia, Costas A. Anastasiou, Mary H. Kosmidis, Efthimios Dardiotis, Antonios N. Gargalionis et al. “Diet Inflammatory Index and Dementia Incidence: A Population-Based Study.” Neurology 97, no. 24 (2021): e2381-e2391.

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Posted February 14, 2022.

Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.

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