Flavonoid-Rich Foods May Lower Dementia Risk

Researchers examined correlations between flavonoid categories, flavodiet scores, and dementia risk in a recent study that was published in JAMA Network Open. They also looked at these relationships in conditions with depression, hypertension, and high genetic risk.

Context
Dementia is a disease characterized by progressive cognitive deterioration that affects thinking, memory, and daily functioning. The sickness is becoming a more significant global health concern due to the lack of viable therapies. It is imperative to use preventive therapies to improve health, reduce costs, and lessen the chance of dementia. Diets high in plant-based foods are associated with a lower prevalence of cognitive impairments, demonstrating the critical role that modifiable risk variables, like food, have in preventing disease.

Flavonoids, found in plant-based foods and beverages, have been linked to a lower risk of dementia, depression, and hypertension. Dietary flavonoids play a part in the gut-brain axis, reduce neuroinflammation, and enhance blood flow in cerebral vascular channels. These diets also have an impact on the brain networks that regulate synaptic plasticity. Developing dietary recommendations for intervention studies and community health initiatives can be aided by identifying foods richer with flavonoids that are linked to improved health outcomes.

About the Study

Researchers found links between the risk of dementia, flavonoid subclasses, and flavonoid ingestion in the current investigation. They also looked at these connections in those who were depressed, hypertensive, and genetically vulnerable.

Researchers examined dietary information from participants in the United Kingdom Biobank, who were recruited between 2006 and 2010 using National Health Service (NHS) registrations and ranged in age from 40 to 70. In addition to completing other biological and physical assessments, participants completed the Oxford WebQ nutrition questionnaire. Each participant supplied two diet records at the very least. Men’s daily caloric consumption ranged from 800 to 4,200 kcal, whereas women’s ranged from 600 to 3,500 kcal.

By summing the intakes of the main contributors to each flavonoid subclass, the researchers created a flavodiet score. They then used the energy intakes of the participants to estimate the cumulative mean. The three meals that consumed the highest amount of each flavonoid subclass were the main contributors. Flavodiet score compliance and flavonoid subclass consumption as determined by 24-hour dietary evaluations were the study exposures.

The main finding concerned dementia with a recent onset and its connections to genetic risk, depression, and hypertension. A high genetic risk for dementia was connected with people in the upper quintile of the Alzheimer’s disease-associated polygenic risk scores (PRS) or with the apolipoprotein E (APOE) ε4 genotype. Dementia was identified using the International Classification of Diseases, Ninth Revision (ICD-9) and ICD-10 codes, which were connected to death registers and hospital records. The dates of censoring for mortality statistics were February 28, 2018 in Wales and March 31, 2021 in Scotland and England. For nine years, or until the censoring date, a dementia diagnosis, or the participants’ death, whichever came first, the researchers monitored the subjects.

The adjusted hazard ratios (AHR) for analysis were obtained using multivariate Cox proportional hazard regressions. Covariates in the study included postmenopausal status, medications, comorbidities, ethnicity, race, sex, education, socioeconomic status, smoking status, sleep duration, physical activity, body mass index (BMI), and scores on the healthy plant-based diet index (hPDI). Data from September 1 to September 30, 2023, were examined by researchers.

In summary
According to the study, eating more foods and drinks high in flavonoids may lower the risk of dementia, particularly in people who are genetically predisposed, experience depression, or have high blood pressure. The results show that eating six more servings of foods strong in flavonoids, such red wine, tea, and berries, can considerably reduce the probability of developing dementia with a new onset, especially in high-risk individuals. Tea has the strongest correlation with a lower incidence of dementia because of epicatechin, a flavonoid that reduces the harmful effects of APOE.

For more information: Flavonoid-Rich Foods, Dementia Risk, and Interactions With Genetic Risk, Hypertension, and Depression, JAMA Netw Open,  doi:10.1001/jamanetworkopen.2024.34136