Adherence to MIND Diet, Genetic Susceptibility, and Incident Dementia in Three US Cohorts

The Mediterranean-dietary approaches to stop hypertension diet intervention for neurodegenerative delay (MIND) diet: a bibliometric analysis

The MIND diet is a healthy dietary pattern that has some benefits for many health outcomes. Our study aims to conduct a bibliometric analysis of the MIND diet, identifying leading edges and hotspots to provide a reference for future research. The research on the MIND diet was gathered from the Web of Science Core Collection (WOSCC) database. For bibliometric analysis, VOSviewer 1.6.16 and the WOSCC Online Analysis Platform were utilized. In total, this comprehensive investigation encompassed 171 documents in the field of the MIND diet. The publications are globally distributed, with contributions from 953 authors across 362 institutions in 37 countries/regions, and published in 94 journals. The United States leads with 72 publications, and Iran and the People's Republic of China also show notable engagement with 28 and 19 publications, respectively. Rush University stands out with 21 publications, followed by Harvard University and Tehran University of Medical Sciences, demonstrating their substantial contributions to this field. Martha Clare Morris is a key figure with 10 publications, alongside Klodian Dhana and Puja Agarwal, each contributing 9 publications, highlighting their influence in the MIND diet research. The journal "Nutrients" is a major publication venue with 20 related articles, followed by "Frontiers in Nutrition" and "Journal of Nutrition Health Aging," reflecting their crucial roles in advancing knowledge about the MIND diet. The first high-cited publication was published in Alzheimers & Dementia and conducted by Martha Clare Morris, which focuses on the MIND diet's relationship with Alzheimer's disease prevention and cognitive decline and emphasizes the diet's neuroprotective potential, highlighting how even moderate adherence can substantially reduce Alzheimer's risk and slow cognitive decline. In conclusion, this is the first comprehensive bibliometric study that quantitatively and qualitatively analyzed the publications in the field of the MIND diet. The MIND diet may be a promising dietary pattern for dementia. However, the current evidence is restricted and highlights the urgency and necessity of further research to investigate the efficacy of this diet for cognitive function. In addition, the MIND diet may have some benefits for other health outcomes, including CVDs, cancer, and diabetes. The number of studies in the field of the MIND diet is limited. More studies are needed, and will give us more knowledge about the MIND diet to improve human health, especially for dementia.

The impact of sustainable diets οn cognitive function in an ageing society: A mini-review

The increasing number of older people raises important health concerns because, in part, of the associated cognitive and functional impairment. The United Nations is taking action with its Decade of Healthy Ageing (2021-2030) campaign, by promoting Sustainable Development Goals and shifting our focus towards more sustainable diets. In this mini-review, sustainable dietary patterns are evaluated, with a focus on healthy plant-based diets, the Mediterranean diet, the Dietary Approaches to Stop Hypertension (DASH) diet, and the Mediterranean-DASH Intervention for Neurodegenerative Delay diet. The review analyzes and describes whether older people's cognitive performance can benefit from the adoption of these sustainable diets. The results of primary studies indicate that the Mediterranean diet and healthy plant-based diets can prevent cognitive impairment by improving cognitive function, language and memory. Plant-based dietary patterns with incorporated Mediterranean foods (high consumption of fruit, vegetables, and fish) are associated with delayed cognitive ageing. Additionally, adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay diet is associated with improved cognitive resilience and lower risk of dementia after 16 years of follow-up. Although consumption of red meat and elevated body mass index are both associated with cognitive dysfunction, some studies have had contradictory findings. Concerns exist regarding the development of chronic diseases, cognitive and functional impairment, as well as disability as age advances. Thus, the policies of the United Nations should ensure healthy ageing for all older individuals. Nonetheless, more research is required to evaluate older people's willingness and readiness to adopt a more sustainable way of eating.

The relationship between gender differences in dietary habits, neuroinflammation, and Alzheimer's disease

Neurocognitive decline is one of the foremost dire issues in medicine today. The mechanisms by which dementia pathogenesis ensues are complicated and multifactorial, particularly in the case of Alzheimer's disease (AD). One irrefutable, yet unexplained factor is the gender disparity in AD, in which women are disproportionately affected by AD, both in the rate and severity of the disease. Examining the multifaceted contributing causes along with unique gender dynamics in modifiable risk factors, such as diet, may lend some insight into why this disparity exists and potential paths forward. The aim of this brief narrative review is to summarize the current literature of gender differences in dietary habits and how they may relate to neuroinflammatory states that contribute to AD pathogenesis. As such, the interplay between diet, hormones, and inflammation will be discussed, along with potential interventions to inform care practices.

The Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) Diet for the Aging Brain: A Systematic Review

The Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diet seems a promising approach to preserve brain function during aging. Previous systematic reviews have demonstrated benefits of the MIND diet for cognition and dementia, though an update is needed. Additionally, other outcomes relevant to brain aging have not been summarized. Therefore, this systematic review aims to give an up-to-date and complete overview on human studies that examined the MIND diet in relation to brain aging outcomes in adults aged ≥40 y. Ovid Medline, Web of Science core collection, and Scopus were searched up to July 25, 2023. Study quality was assessed using the Newcastle-Ottawa Scale and the Cochrane Risk-of-Bias tool. We included 40 articles, of which 32 were unique cohorts. Higher MIND diet adherence was protective of dementia in 7 of 10 cohorts. Additionally, positive associations were demonstrated in 3 of 4 cohorts for global cognition and 4 of 6 cohorts for episodic memory. The protective effects of the MIND diet on cognitive decline are less apparent, with only 2 of 7 longitudinal cohorts demonstrating positive associations for global decline and 1 of 6 for episodic memory decline. For other brain outcomes (domain-specific cognition, cognitive impairments, Parkinson's disease, brain volume, and pathology), results were mixed or only few studies had been performed. Many of the cohorts demonstrating protective associations were of North American origin, raising the question if the most favorable diet for healthy brain aging is population-dependent. In conclusion, this systematic review provides observational evidence for protective associations between the MIND diet and global cognition and dementia risk, but evidence for other brain outcomes remains mixed and/or limited. The MIND diet may be the preferred diet for healthy brain aging in North American populations, though evidence for other populations seems less conclusive. This review was registered at PROSPERO as CRD42022254625.

The Role of Diet and Gut Microbiota in Alzheimer's Disease

Alzheimer's disease (AD), the most prevalent form of dementia, is characterized by the accumulation of amyloid-beta (Aβ) plaques and hyperphosphorylated tau tangles. Currently, Alzheimer's disease (AD) impacts 50 million individuals, with projections anticipating an increase to 152 million by the year 2050. Despite the increasing global prevalence of AD, its underlying pathology remains poorly understood, posing challenges for early diagnosis and treatment. Recent research suggests a link between gut dysbiosis and the aggregation of Aβ, the development of tau proteins, and the occurrence of neuroinflammation and oxidative stress are associated with AD. However, investigations into the gut-brain axis (GBA) in the context of AD progression and pathology have yielded inconsistent findings. This review aims to enhance our understanding of microbial diversity at the species level and the role of these species in AD pathology. Additionally, this review addresses the influence of confounding elements, including diet, probiotics, and prebiotics, on AD throughout different stages (preclinical, mild cognitive impairment (MCI), and AD) of its progression.

Alzheimer's Disease Treatment: The Search for a Breakthrough

As the search for modalities to cure Alzheimer's disease (AD) has made slow progress, research has now turned to innovative pathways involving neural and peripheral inflammation and neuro-regeneration. Widely used AD treatments provide only symptomatic relief without changing the disease course. The recently FDA-approved anti-amyloid drugs, aducanumab and lecanemab, have demonstrated unclear real-world efficacy with a substantial side effect profile. Interest is growing in targeting the early stages of AD before irreversible pathologic changes so that cognitive function and neuronal viability can be preserved. Neuroinflammation is a fundamental feature of AD that involves complex relationships among cerebral immune cells and pro-inflammatory cytokines, which could be altered pharmacologically by AD therapy. Here, we provide an overview of the manipulations attempted in pre-clinical experiments. These include inhibition of microglial receptors, attenuation of inflammation and enhancement of toxin-clearing autophagy. In addition, modulation of the microbiome-brain-gut axis, dietary changes, and increased mental and physical exercise are under evaluation as ways to optimize brain health. As the scientific and medical communities work together, new solutions may be on the horizon to slow or halt AD progression.

Association of the Mediterranean Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) Diet With the Risk of Dementia

Importance

Dementia threatens the well-being of older adults, making efforts toward prevention of great importance.

Objective

To evaluate the association of the Mediterranean-Dietary Approaches to Stop Hypertension (DASH) Intervention for Neurodegenerative Delay (MIND) diet with the risk of dementia in 3 prospective studies and a meta-analysis.

Design, Setting, and Participants

Cohort analyses included the Whitehall II study (WII), the Health and Retirement Study (HRS), and the Framingham Heart Study Offspring cohort (FOS), and the meta-analysis included 11 cohort studies. Participants were middle-aged and older women and men from WII in 2002 to 2004, HRS in 2013, and FOS in 1998 to 2001 without dementia at the study baseline. Data were analyzed from May 25 to September 1, 2022.

Exposures

MIND diet score was measured using food frequency questionnaires, and scores ranged from 0 to 15, with a higher score indicating higher adherence to the MIND diet.

Main Outcome and Measures

Incident all-cause dementia, with cohort-specific definitions.

Results

Included in this study were 8358 participants (mean [SD] age, 62.2 [6.0] years; 5777 male [69.1%]) from WII, 6758 participants (mean [SD] age, 66.5 [10.4] years; 3965 female [58.7%]) from HRS, and 3020 participants (mean [SD] age, 64.2 [9.1] years; 1648 female [54.6%]) from FOS. The mean (SD) baseline MIND diet score was 8.3 (1.4) in WII, 7.1 (1.9) in HRS, and 8.1 (1.6) in FOS. Over 166 516 person-years, a total of 775 participants (220 in WII, 338 in HRS, and 217 in FOS) developed incident dementia. In the multivariable-adjusted Cox proportional hazard model, higher MIND diet score was associated with lower risk of dementia (pooled hazard ratio [HR] for every 3-point increment, 0.83; 95% CI, 0.72-0.95; P for trend = .01; I2 = 0%). The associations were consistently observed in subgroups defined by sex, age, smoking status, and body mass index. In the meta-analysis of 11 cohort studies with 224 049 participants (5279 incident dementia cases), the highest tertile of MIND diet score was associated with lower risk of dementia compared with the lowest tertile (pooled HR, 0.83; 95% CI, 0.76-0.90; I2 = 35%).

Conclusions and Relevance

Results suggest that adherence to the MIND diet was associated with lower risk of incident dementia in middle-aged and older adults. Further studies are warranted to develop and refine the specific MIND diet for different populations.

Dietary Responses of Dementia-Related Genes Encoding Metabolic Enzymes

The age-related loss of the cognitive function is a growing concern for global populations. Many factors that determine cognitive resilience or dementia also have metabolic functions. However, this duality is not universally appreciated when the action of that factor occurs in tissues external to the brain. Thus, we examined a set of genes involved in dementia, i.e., those related to vascular dementia, Alzheimer's disease, Parkinson's disease, and the human metabolism for activity in 12 metabolically active tissues. Mining the Genotype-Tissue Expression (GTEx) data showed that most of these metabolism-dementia (MD) genes (62 of 93, 67%) exhibit a higher median expression in any of the metabolically active tissues than in the brain. After identifying that several MD genes served as blood-based biomarkers of longevity in other studies, we examined the impact of the intake of food, nutrients, and other dietary factors on the expression of MD genes in whole blood in the Framingham Offspring Study (n = 2134). We observed positive correlations between flavonoids and HMOX1, taurine and UQCRC1, broccoli and SLC10A2, and myricetin and SLC9A8 (p < 2.09 × 10^-4). In contrast, dairy protein, palmitic acid, and pie were negatively correlated, respectively, with the expression of IGF1R, CSF1R, and SLC9A8, among others (p < 2.92 × 10^-4). The results of this investigation underscore the potential contributions of metabolic enzyme activity in non-brain tissues to the risk of dementia. Specific epidemiological or intervention studies could be designed using specific foods and nutrients or even dietary patterns focused on these foods and nutrients that influence the expression of some MD genes to verify the findings presented here.

Whole Dietary Patterns, Cognitive Decline and Cognitive Disorders: A Systematic Review of Prospective and Intervention Studies

Dementia prevalence is a global public health concern. Adherence towards a healthy dietary pattern (DP) may reduce the risk of cognitive decline and dementia. This narrative systematic review aimed to synthesise prospective and intervention study data to evaluate the impact of a-posteriori and a-priori derived DPs on cognitive ageing, from cognitive decline to incident dementia. Ninety-three studies were included: 83 prospective studies and 10 randomised controlled trials (RCT). Most prospective studies (77%) examined a-priori DPs, with the Mediterranean diet examined most frequently. A total of 52% of prospective and 50% of RCTs reported a protective relationship between 'healthy' DPs and global cognitive decline. Overall, 59% of prospective studies reported positive associations between healthy DPs and risk of cognitive disorder. Incident cognitive disorder was examined by only one intervention study (subgroup analysis) which reported a beneficial effect of a low-fat diet on risk of probable dementia in women. Unhealthy DPs were examined less frequently (n = 17; 21%), with 41% of these studies reporting associations between adherence and poorer cognitive outcomes. Overall, there were mixed results for healthy and unhealthy DPs on cognition, likely due to between-study heterogeneity. Standardisation of diet exposure and cognitive outcome measurement would help to reduce this. Future research would benefit from investigating effects of culturally appropriate DPs on individual cognitive domains and incident cognitive disorders in diverse and high-risk populations.

MIND Dietary Pattern and Its Association with Cognition and Incident Dementia in the UK Biobank

A high adherence to the Mediterranean-Dietary Approaches to Stop Hypertension Diet Intervention for Neurodegenerative Delay (MIND) has been associated with better cognition and a lower risk of dementia in some but not all studies. We measured adherence to MIND and its association with cognitive health in the UK Biobank (UKB). A MIND score was derived from 24 h diet recall questionnaires for 120,661 participants who completed at least one of seven self-administered cognitive function tests. In a subset of 78,663 participants aged 55+, diagnosis of dementia was determined by linked hospital and death records. Multivariable regression and Cox proportional hazard ratio (HR) models were used to examine associations of MIND with cognitive ability and incident dementia. Higher adherence to MIND was associated with a small but significant worsening in performance on five of seven cognitive tests (p < 0.002). Associations were strongest among highly educated participants (p < 0.002 for MIND × education interaction). After a mean follow-up time of 10.5 years, 842 participants developed dementia. Overall, MIND adherence was not associated with incident dementia. An inverse association was observed among females (HR = 0.87 per score standard deviation (SD), p = 0.008) but not males (HR = 1.09, p = 0.11) (p = 0.008 for MIND × sex interaction). Similar associations with cognitive ability and dementia were observed for the Alternative Healthy Eating Index-2010 (AHEI-2010) dietary pattern. Associations were not modified by genetic susceptibility. In UKB, the MIND diet was not associated with better cognitive test scores and only with lower dementia risk in women.

Systematic Review on the Potential Effect of Berry Intake in the Cognitive Functions of Healthy People

The increase in life expectancy poses health challenges, such as increasing the impairment of cognitive functions. Berries show a neuroprotective effect thanks to flavonoids, able to reduce neuroinflammatory and to increase neuronal connections. The aim of this systematic review is to explore the impact of berries supplementation on cognitive function in healthy adults and the elderly. Twelve studies were included for a total of 399 participants, aged 18–81 years (mean age: 41.8 ± 4.7 years). Six studies involved young adults (23.9 ± 3.7 years), and four studies involved the elderly (60.6 ± 6.4 years). Most studies investigated effects of a single berry product, but one used a mixture of 4 berries. Non-significant differences were detected across cognition domains and methodologies, but significant and positive effects were found for all cognitive domains (attention and concentration, executive functioning, memory, motor skills and construction, and processing speed), and in most cases they were present in more than one study and detected using different methodologies. Although some limitations should be taken into account to explain these results, the positive findings across studies and methodologies elicit further studies on this topic, to endorse the consumption of berries in healthy populations to prevent cognitive decline.