Mediterranean diet, healthy eating index 2005, and cognitive function in middle-aged and older Puerto Rican adults

Healthy Dietary Pattern Improves Cognitive Function in Elderly Persons With Periodontitis: A Cross-Sectional Study of NHANES

AIM

Cognitive decline is thought to be more prevalent in elderly persons with periodontitis. Greater adherence to Healthy Eating Index (HEI)-2015 has been reported to improve cognitive function in the elderly population. However, whether the benefits of HEI-2015 on cognitive function apply to elderly patients with periodontitis remains unknown.

METHODS

This is a cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES). The data were extracted from database 2011-2014. Cognitive function was measured through the Consortium to Establish a Registry for Alzheimer's Disease battery for immediate recall (CERAD-WL) and delayed recall (CERAD-DR), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). The data of HEI-2015 were acquired from 24-hour dietary recalls. Weighted linear regression models were performed to investigate the association between HEI-2015 and cognitive function in elderly patients with periodontitis. The associations were further investigated in subgroups of sex, cardiovascular disease status, and depression status.

RESULTS

A total of 1862 participants were included, and 1223 of them had periodontitis. Periodontitis was negatively associated with cognitive function (β = -0.45; 95% confidence interval [CI], -0.87 to -0.03). No statistically significant relationship was observed between HEI-2015 and cognitive function (β = 0.33; 95% CI, -0.02 to 0.69). Low HEI-2015 score was associated with high odds of cognitive decline in patients with periodontitis (β = -0.73; 95% CI, -1.25 to -0.21; P for trend = .01). Higher HEI-2015 was related to the lower incidence of cognitive function decline in patients with periodontitis who were female (β = -0.53; 95% CI, -1.03 to -0.03), had a socioeconomic status from 0 to 3 (β = -0.55; 95% CI, -1.00 to -0.09), did not have cardiovascular disease (β = -0.60; 95% CI, -1.14 to -0.05), and did not have depression (β = -0.57; 95% CI, -1.11 to -0.03).

CONCLUSIONS

Greater HEI-2015 adherence may improve cognitive function amongst elderly patients with periodontitis. Further studies are needed to investigate this putative association in elderly persons with periodontitis.

Brain responses to intermittent fasting and the healthy living diet in older adults

Diet may promote brain health in metabolically impaired older individuals. In an 8-week randomized clinical trial involving 40 cognitively intact older adults with insulin resistance, we examined the effects of 5:2 intermittent fasting and the healthy living diet on brain health. Although intermittent fasting induced greater weight loss, the two diets had comparable effects in improving insulin signaling biomarkers in neuron-derived extracellular vesicles, decreasing the brain-age-gap estimate (reflecting the pace of biological aging of the brain) on magnetic resonance imaging, reducing brain glucose on magnetic resonance spectroscopy, and improving blood biomarkers of carbohydrate and lipid metabolism, with minimal changes in cerebrospinal fluid biomarkers for Alzheimer's disease. Intermittent fasting and healthy living improved executive function and memory, with intermittent fasting benefiting more certain cognitive measures. In exploratory analyses, sex, body mass index, and apolipoprotein E and SLC16A7 genotypes modulated diet effects. The study provides a blueprint for assessing brain effects of dietary interventions and motivates further research on intermittent fasting and continuous diets for brain health optimization. For further information, please see ClinicalTrials.gov registration: NCT02460783.

Nutritional Barriers to the Adherence to the Mediterranean Diet in Non-Mediterranean Populations

Adherence to the Mediterranean diet has been shown to lower the risk of developing chronic non-communicable diseases like cardiovascular and neurodegenerative diseases and cancer. Improvements in depression, participation in daily activities in older individuals, weight loss and a reduction in adverse pregnancy outcomes are associated with adherence to the Mediterranean diet. The number of studies that have evaluated barriers to adherence to the Mediterranean diet in the US and, in particular, in racial and ethnic minority populations within the US are few. Among Native American and Alaskan Native populations, studies evaluating traditional or alternative Mediterranean diet adherence for chronic non-infectious diseases is unavailable. Mediterranean diet scoring instruments used in studies in European and Mediterranean countries and among white participants in the US fail to capture the dietary patterns of racial and ethnic minority populations. In this narrative review, the food components of the traditional Mediterranean diet are discussed, adherence to the Mediterranean diet is examined in Mediterranean and non-Mediterranean countries and barriers preventing adherence to the Mediterranean diet in the US and among racial and ethnic minority populations is reviewed. Recommendations for improving nutrition education and intervention and for increasing adherence and cultural adaptions to the Mediterranean diet are provided.

New Insights into the Relationship between Nutrition and Neuroinflammation in Alzheimer's Disease: Preventive and Therapeutic Perspectives

Neurodegenerative diseases are progressive brain disorders characterized by inexorable synaptic dysfunction and neuronal loss. Since the most consistent risk factor for developing neurodegenerative diseases is aging, the prevalence of these disorders is intended to increase with increasing life expectancy. Alzheimer's disease is the most common cause of neurodegenerative dementia, representing a significant medical, social, and economic burden worldwide. Despite growing research to reach an early diagnosis and optimal patient management, no disease-modifying therapies are currently available. Chronic neuroinflammation has been recognized as a crucial player in sustaining neurodegenerative processes, along with pathological deposition of misfolded proteins, including amyloid-β and tau protein. Modulating neuroinflammatory responses may be a promising therapeutic strategy in future clinical trials. Among factors that are able to regulate neuroinflammatory mechanisms, diet, and nutrients represent easily accessible and modifiable lifestyle components. Mediterranean diet and several nutrients, including polyphenols, vitamins, and omega-3 polyunsaturated fatty acids, can exert antioxidant and anti-inflammatory properties, impacting clinical manifestations, cognitive decline, and dementia. This review aims to provide an updated overview of the relationship between neuroinflammation, nutrition, gut microbiota, and neurodegeneration. We summarize the major studies exploring the effects of diet regimes on cognitive decline, primarily focusing on Alzheimer's disease dementia and the impact of these results on the design of ongoing clinical trials.

Inflammatory Pathways in Overweight and Obese Persons as a Potential Mechanism for Cognitive Impairment and Earlier Onset Alzeihmer's Dementia in the General Population: A Narrative Review

The overweight status or obesity can be confirmed through classical methods such as the body mass index (BMI) and the waist-to-hip ratio (WHR). Apart from metabolic issues such as atherosclerosis, liver steatosis, or diabetes mellitus, long-term obesity or overweight status can pose a risk for cardiovascular and neurovascular complications. While some acute adverse events like coronary syndromes of strokes are well-documented to be linked to an increased body mass, there are also chronic processes that, due to their silent onset and evolution, are underdiagnosed and not as thoroughly studied. Through this review, we aimed to collect all relevant data with regard to the long-term impact of obesity on cognitive function in all ages and its correlation with an earlier onset of dementia such as Alzheimer's disease (AD). The exact mechanisms through which a decline in cognitive functions occurs in overweight or obese persons are still being discussed. A combination of factors has been acknowledged as potential triggers, such as a sedentary lifestyle and stress, as well as a genetic predisposition, for example, the apolipoprotein E (ApoE) alleles in AD. Most research highlights the impact of vascular dysfunction and systemic inflammation on the nervous system in patients with obesity and the subsequent neurological changes. Obesity during the early to mid-ages leads to an earlier onset of cognitive dysfunction in various forms. Also, lifestyle intervention can reverse cognitive dysfunction, especially dieting, to encourage weight loss.

The impact of diabetes in cognitive impairment: A review of current evidence and prospects for future investigations

Cognitive impairment in individuals with diabetes represents a multifaceted and increasingly prevalent health concern. This review critically examines the current evidence regarding the intricate relationship between diabetes and cognitive decline. It highlights the existing knowledge on the impact of diabetes on cognitive function, spanning from mild cognitive impairment to dementia, including vascular and Alzheimer dementia. The review underscores the need for a standardized diagnostic paradigm and explores research gaps, such as the implications of cognitive impairment in younger populations and various diabetes types. Furthermore, this review emphasizes the relevance of diabetes-related comorbidities, including hypertension and dyslipidemia, in influencing cognitive decline. It advocates for a comprehensive, interdisciplinary approach, integrating insights from neuroscience, endocrinology, and immunology to elucidate the mechanistic underpinnings of diabetes-related cognitive impairment. The second part of this review outlines prospective research directions and opportunities. It advocates for longitudinal studies to understand disease progression better and identifies critical windows of vulnerability. The search for accurate biomarkers and predictive factors is paramount, encompassing genetic and epigenetic considerations. Personalized approaches and tailored interventions are essential in addressing the substantial variability in cognitive outcomes among individuals with diabetes.

Christian Orthodox Fasting as a Traditional Diet with Low Content of Refined Carbohydrates That Promotes Human Health: A Review of the Current Clinical Evidence

INTRODUCTION

Christian Orthodox fasting is a pattern high in complex carbohydrates and low in refined carbohydrates. It has been explored in association with its potential health benefits. The present review aims to comprehensively explore the existing available clinical data concerning the potential favorable impact of the dietary pattern of Christian Orthodox fasting on human health.

METHODS

PubMed database, Web of Science and Google Scholar were extensively searched in order to identify the more appropriate clinical studies that explore the effect of Christian Orthodox fasting on health-related outcomes in humans utilizing relative keywords. We initially retrieved 121 records through database searching. After applying several exclusion criteria, 17 clinical studies were finally included in this review study.

DISCUSSION

Christian Orthodox fasting showed beneficial effects concerning glucose and lipid control, whereas the data for blood pressure remain inconclusive. Concerning weight control, fasters were characterized by lower body mass and lower caloric intake in the course of the fasting periods. During fasting, this pattern is higher in fruits and vegetables, showing the absence of dietary deficiencies for iron and folate. Nevertheless, dietary deficiencies were recorded for calcium and vitamin B2, and also hypovitaminosis D has been noticed in monks. Interestingly, the vast majority of monks do present with both good quality of life and mental health.

CONCLUSIONS

Overall, Christian Orthodox fasting is a dietary pattern low in refined carbohydrates and high in complex carbohydrates and fiber that may be beneficial for human health promotion and chronic disease prevention. However, further studies are strongly recommended on the impact of long-term religious fasting on HDL cholesterol levels and blood pressure.

Adherence to Mediterranean Diet and Depressive Symptomatology Among Boston Area Puerto Ricans

BACKGROUND

Higher Mediterranean diet (MeD) adherence has been linked with lower depressive symptomatology, but research examining this association is limited, especially among Latinos, including mainland U.S. Puerto Ricans. Hence, we examined cross-sectional and longitudinal associations between MeD adherence and self-reported depressive symptomatology in Boston area Puerto Rican adults.

METHODS

The Center for Epidemiologic Studies Depression Scale (CES-D) was used to evaluate depressive symptoms. Adherence to MeD was assessed at all 3 visits. We used multivariable linear regression for baseline cross-sectional analysis, and linear mixed effects modeling over 3 waves of follow-up for longitudinal analysis. We also assessed whether baseline MeD adherence affected 5y CES-D trajectory. We conducted sensitivity analyses among participants without diabetes, and among participants with complete MeD and CES-D measures at all visits.

RESULTS

MeD adherence was significantly associated with CES-D score at baseline (β = -2.0, 95% confidence interval [CI] -4.0, -0.04 for highest vs lowest tertile, p trend = .04) and across 3 waves (β = -1.9, 95% CI = -3.0, -0.8 for highest vs lowest tertile, p trend = .0005). Results were similar in analyses restricted to participants without diabetes, as well as among participants with complete CES-D and MeD scores at all visits.

CONCLUSIONS

While CES-D score was consistently lower in those with higher MeD adherence over 5 years of follow up, no relationship between baseline MeD adherence and 5y CES-D trajectory was observed.

Multicultural Healthy Diet to Reduce Cognitive Decline & Alzheimer's Disease Risk: Study protocol for a pilot randomized controlled trial

BACKGROUND

Emerging evidence indicates that healthy dietary patterns are associated with higher cognitive status; however, few clinical trials have explored this association in diverse middle-aged adults before the onset of cognitive decline. We use novel ambulatory methods to assess cognition in natural settings in tandem with diet recording.

AIMS

We investigate whether the Multicultural Healthy Diet Study to Reduce Cognitive Decline & Alzheimer's Disease Risk, a pilot randomized controlled trial of an anti-inflammatory dietary pattern compared to usual diet, can mitigate cognitive decline and Alzheimer's Disease risk in a diverse population of 40-65 year old adults in Bronx, New York.

METHODS

Primary cognitive outcomes assessed at nine months are collected in an ecological momentary assessment "measurement burst" design, over the course of participants' daily lives. These ultra-brief, ambulatory cognitive assessments examine processing speed, visuospatial working memory, short-term associative memory binding, long-term associative memory, and working memory capacity. Key secondary outcomes relate to comparing dietary intake between study arms with respect to cognitive outcomes. We assess diet with food records using the National Cancer Institute's Automated Self-Administered 24-h record and serum biomarkers. We further investigate the association of self-reported diet and dietary biomarkers with inflammatory-based biomarkers.

CONCLUSION

This randomized controlled trial of diet and cognition for the first time combines novel measures of ambulatory cognitive assessment with web-based assessment of dietary intake recording. This new approach enabled the study to continue in the midst of the COVID-19 pandemic in remote format.

Association of Mediterranean Diet With Cognitive Decline Among Diverse Hispanic or Latino Adults From the Hispanic Community Health Study/Study of Latinos

IMPORTANCE

The Mediterranean diet may reduce the burden of Alzheimer disease and other associated dementias in Hispanic or Latino people.

OBJECTIVE

To investigate the association of a Mediterranean diet with cognitive performance among community-dwelling Hispanic or Latino adults.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) and the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA), an HCHS/SOL ancillary study. Cognition tests were administered in the HCHS/SOL from March 2008 to June 2011 (visit 1) and in the SOL-INCA from October 2015 to March 2018 (visit 2). Participants included in the present study had completed a diet assessment at visit 1 and neurocognitive evaluations at visits 1 and 2. Data were analyzed from September 2021 to May 2022.

EXPOSURES

Mediterranean diet adherence was ascertained using the Mediterranean diet score (MDS) and was categorized as low (MDS: 0-4 points), moderate (MDS: 5-6 points), or high (MDS: 7-9 points). The mean of two 24-hour dietary recalls was used to calculate the MDS.

MAIN OUTCOMES AND MEASURES

Cognitive change between visits 1 and 2 was calculated by subtracting the cognitive score at visit 2 from the cognitive score at visit 1 and adjusting by the time elapsed between visits and cognitive score at visit 1. Neurocognitive tests administered were Brief Spanish-English Verbal Learning Test (B-SEVLT) Sum, B-SEVLT Recall, word fluency, and Digit Symbol Substitution Test (DSST). Results of each test were z score-transformed and the means were averaged to create a global cognition score. Complex sample linear regression analysis was used to ascertain the association between MDS and neurocognitive performance at each visit and neurocognitive change.

RESULTS

A total of 6321 participants (mean [SE] age, 56.1 [0.18] years at visit 1; n = 4077 women [57.8%]) were included. Mediterranean diet adherence weighted frequencies were 35.8% (n = 2112 of 6321) for the low adherence group, 45.4% (n = 2795) for the moderate adherence group, and 18.8% (n = 1414) for the high adherence group. In the fully adjusted model, z score-transformed cognitive scores at visit 1 in the high vs low adherence groups were higher for B-SEVLT Sum (β = 0.11; 95% CI, 0.02-0.20), B-SEVLT Recall (β = 0.16; 95% CI, 0.07-0.25), and global cognition (β = 0.10; 95% CI, 0.04-0.16) tests. In the mean follow-up time of 7 years, cognitive change in the high vs low adherence groups was less pronounced for B-SEVLT Sum (β = 0.12; 95% CI, 0.05-0.20) and B-SEVLT Recall (β = 0.14; 95% CI, 0.05-0.23), but not for word fluency, DSST score, or global cognition score.

CONCLUSIONS AND RELEVANCE

Results of this cohort study suggested that high adherence to a Mediterranean diet was associated with better cognitive performance and decreased 7-year learning and memory decline among middle-aged and older Hispanic or Latino adults. Culturally tailored Mediterranean diet may reduce the risk of cognitive decline and Alzheimer disease in this population.

Associations between diet quality scores and central obesity among adults in Puerto Rico

BACKGROUND

Adults in Puerto Rico experience an excessive burden of central obesity. It remains unknown which dietary components are more strongly associated with central obesity in this high-risk group. We aimed to evaluate the relationship of the Mediterranean diet (MeDS) and Alternate Healthy Eating Index 2010 (AHEI) with central obesity in the Puerto Rico Assessment of Diet, Lifestyle and Diseases (PRADLAD) cross-sectional study.

METHODS

Data from PRADLAD participants (ages 30-75 years) were used (n = 166). Dietary intake was assessed by food frequency questionnaire. The MeDS [nine components; range: 0 (lowest) to 9 (highest observance of a Mediterranean-like diet)] and AHEI [11 components; range: 0 (lowest) to 110 (highest diet quality)] were defined. Daily intake of foods and beverages within each MeDS component was ranked by contribution to total energy intake. Multivariable logistic regression was used to evaluate associations between MeDS and AHEI with central obesity (waist circumference > 102 cm males, > 88 cm females).

RESULTS

Mean ± SD MeDS was 4.46 ± 1.77 and AHEI was 60.2 ± 11.1. Traditional foods representative of the MeDS included potatoes, root vegetables, fruit juice, avocados, bread, oatmeal, beans, chicken, seafood, low-fat milk, cheese, eggs and beer. Adjusted odds ratios and 95% confidence intervals of central obesity were 0.78 (0.63-0.97) per unit increment of MeDS and 0.61 (0.42-0.90) per 10-unit increment of AHEI.

CONCLUSIONS

Higher adherence to MeDS or AHEI was associated with lower central obesity in adults in Puerto Rico. Consuming traditional foods reflecting these dietary patterns (i.e., Mediterranean-like) may reduce central obesity in high-risk populations.

Association between healthy eating index-2015 and various cognitive domains in US adults aged 60 years or older: the National Health and Nutrition Examination Survey (NHANES) 2011-2014

BACKGROUND

Diet, as a modifiable factor, plays an important role in cognitive function. However, the association between adherence to the 2015-2020 Dietary Guidelines for Americans (DGA), measured by Healthy Eating Index (HEI)-2015, and cognitive function remains unclear. This study aims to explore whether HEI-2015 is associated with various cognitive domains and whether such association is modified by age, gender, or ethnicity in the US adults aged 60 years or older using data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014.

METHODS

HEI-2015 scores were calculated from 24-h dietary recall interviews. Cognitive function was evaluated by Digit Symbol Substitution Test (DSST, a measure of processing speed), Animal Fluency Test (AFT, a measure of executive function), a subtest from Consortium to Establish a Registry for Alzheimer's disease (CERAD, a measure of memory), and a composite-z score calculated by summing z scores of individual tests. The associations between HEI-2015 scores and cognitive performance were explored using multiple linear regression models.

RESULTS

A total of 2450 participants aged 60 years or older were included. Participants with higher HEI-2015 scores were more likely to have higher DSST, AFT as well as composite-z scores (P<0.05). Significant interaction effects were identified between HEI-2015 and ethnicity in specific cognitive domains (P_interaction<0.05). Among HEI-2015 components, higher intakes of whole fruits and seafood and plant protein were associated with better cognitive performance (P<0.05).

CONCLUSION

Higher adherence to DGA is associated with better cognitive performance, especially regarding processing speed and executive function among the US adults aged 60 years or older.

Changes in Diet Quality from Mid- to Late Life Are Associated with Cognitive Impairment in the Singapore Chinese Health Study

BACKGROUND

Although higher diet quality at mid-life has been associated with better cognitive function in late adulthood, it is unclear whether dietary improvement after mid-life may reduce the risk of cognitive impairment.

OBJECTIVES

We examined associations between changes in diet quality and risk of cognitive impairment in the Singapore Chinese Health Study cohort.

METHODS

We used data from 14,683 Chinese men and women who were recruited at ages 45 to 74 y from 1993 to 1998 and re-interviewed after 20 y at ages 61 to 96 y during follow-up 3 (2014-2016). Diet quality was measured using the Dietary Approaches to Stop Hypertension (DASH) scores at baseline and follow-up 3 interviews. Cognitive impairment was defined using scores from the Singapore-modified Mini-Mental State Examination at the follow-up 3 interview. Multivariable logistic regression models were used to estimate ORs and 95% CIs for the associations between change in DASH scores and cognitive impairment.

RESULTS

Higher quintiles in DASH scores at baseline and follow-up 3 interviews were associated with lower odds of cognitive impairment in a dose-dependent manner (both: P-trend < 0.001). Compared with participants with consistently low DASH scores, the OR (95% CI) of cognitive impairment was lowest, at 0.64 (0.51, 0.79), in those with consistently high DASH scores. Those with small (OR: 0.80, 95% CI: 0.65, 0.98) or moderate-large (OR: 0.72, 95% CI: 0.59, 0.86) increases in DASH scores were associated with significantly lower odds of cognitive impairment than those with consistently low DASH scores. Associations were consistent across subgroups by sex, BMI (kg/m2; <23 or ≥23), and age (<60 y, ≥60 y) at baseline.

CONCLUSIONS

Although maintaining high diet quality confers the lowest risk, improving diet quality from mid- to late life was still associated with a lower risk of cognitive impairment in late adulthood.

Associations of dietary markers with brain volume and connectivity: A systematic review of MRI studies

The high prevalence of unhealthy dietary patterns and related brain disorders, such as dementia, emphasizes the importance of research that examines the effect of dietary factors on brain health. Identifying markers of brain health, such as volume and connectivity, that relate to diet is an important first step towards understanding the lifestyle determinants of healthy brain ageing. We conducted a systematic review of 52 studies (total n = 21,221 healthy participants aged 26-80 years, 55 % female) that assessed with a range of MRI measurements, which brain areas, connections, and cerebrovascular factors were associated with dietary markers. We report associations between regional brain measures and dietary health. Collectively, lower diet quality was related to reduced brain volume and connectivity, especially in white and grey matter of the frontal, temporal and parietal lobe, cingulate, entorhinal cortex and the hippocampus. Associations were also observed in connecting fibre pathways and in particular the default-mode, sensorimotor and attention networks. However, there were also some inconsistencies in research methods and findings. We recommend that future research use more comprehensive and consistent dietary measures, more representative samples, and examine the role of key subcortical regions previously highlighted in relevant animal work.

Dietary patterns in middle age: effects on concurrent neurocognition and risk of age-related cognitive decline

Context

Diet plays a critical role in cognitive integrity and decline in older adults. However, little is known about the relationship between diet and cognitive integrity in middle age.

Objective

To investigate the relationship between dietary patterns in healthy middle-aged adults and neurocognition both in middle age and later in life.

Data Sources

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, the following electronic databases were searched: Web of Science, Scopus, PubMed, and PsychInfo.

Data Extraction

Data from eligible articles was extracted by 2 reviewers.

Data Analysis

Articles included in the systematic review were synthesized (based on the synthesis without meta-analysis reporting guidelines) and assessed for quality (using the Joanna Briggs Institute checklist for randomized controlled trials, cohort studies, and cross-sectional studies) by 2 reviewers.

Results

Of 1558 studies identified, 34 met the eligibility criteria for inclusion. These comprised 9 cross-sectional studies, 23 longitudinal or prospective cohort studies, and 2 randomized controlled trials. Findings were mixed, with some studies reporting a significant positive relationship between adherence to various “healthy” dietary patterns and neurocognition, but others reporting no such relationship.

Conclusion

This systematic review demonstrated that adherence to the Mediterranean diet and other healthy dietary patterns in middle age can protect neurocognition later in life.

Systematic Review Registration

PROSPERO registration no. CRD42020153179.

Mediterranean diet adherence is associated with better cognitive status and less depressive symptoms in a Greek elderly population

PURPOSE

To evaluate the Mediterranean diet (MD) adherence of an elderly Greek population, and its association with the grade of cognitive decline and psychological status.

METHODS

Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Mediterranean diet score (MedDietScore) questionnaires were used to assess the impact of MD adherence on cognitive abilities and psychological state of a Greek elderly population.

PARTICIPANTS

2092 men and women over 65 years old (mean age 74.97 ± 8.41 years) from seven different Greek cities RESULTS: 34.4% of the study population showed cognitive impairment, while 32.3% of the participants had depressive symptoms. More than half of the participants (52.1%) showed very low or low MD adherence. Higher MD adherence was significantly associated with better MMSE and GDS scores. Moreover, higher MD adherence was significantly associated with younger age, female gender, higher educational level, and better anthropometric parameters. MD adherence was independently associated with cognitive and psychological status, and gender after adjustment for potential confounders.

CONCLUSION

Higher MD adherence is strongly associated with better cognitive status and less depressive symptomatology. Public health policies are recommended to focus on the promotion of the MD, as a crucial strategy to reduce the risk of cognitive impairment and depression.

Race/ethnicity and gender modify the association between diet and cognition in U.S. older adults: National Health and Nutrition Examination Survey 2011-2014

INTRODUCTION

It is unclear whether the association between Mediterranean-type Diet (MeDi) and cognition is similar across different racial/ethnic groups or between women and men.

METHODS

The current study included 2435 participants (≥60 years of age) of the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Linear regression models were applied to examine the association between diet and cognition, adjusted for multiple demographic variables. Interaction between MeDi and race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, other), and between MeDi and gender, were examined, followed by stratified analyses.

RESULTS

One score increase in MeDi was associated with 0.039 (95%confidence interval [CI] = 0.016-0.062) higher global cognitive z-score. Significant associations between MeDi and global cognition and between MeDi and immediate recall were found in the non-Hispanic Whites only (P-interaction = 0.057 and 0.059, respectively). MeDi was associated with increased score of animal fluency score in men but not in women (P-interaction = 0.082).

DISCUSSION

The positive association between MeDi and cognition might be dependent on race/ethnicity and gender.

Can Healthy Diets, Regular Exercise, and Better Lifestyle Delay the Progression of Dementia in Elderly Individuals?

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss and multiple cognitive impairments. Current healthcare costs for over 50 million people afflicted with AD are about $818 million and are projected to be $2 billion by 2050. Unfortunately, there are no drugs currently available that can delay and/or prevent the progression of disease in elderly individuals and in AD patients. Loss of synapses and synaptic damage are largely correlated with cognitive decline in AD patients. Women are at a higher lifetime risk of developing AD encompassing two-thirds of the total AD afflicted population. Only about 1-2% of total AD patients can be explained by genetic mutations in APP, PS1, and PS2 genes. Several risk factors have been identified, such as Apolipoprotein E4 genotype, type 2 diabetes, traumatic brain injury, depression, and hormonal imbalance, are reported to be associated with late-onset AD. Strong evidence reveals that antioxidant enriched diets and regular exercise reduces toxic radicals, enhances mitochondrial function and synaptic activity, and improves cognitive function in elderly populations. Current available data on the use of antioxidants in mouse models of AD and antioxidant(s) supplements in diets of elderly individuals were investigated. The use of antioxidants in randomized clinical trials in AD patients was also critically assessed. Based on our survey of current literature and findings, we cautiously conclude that healthy diets, regular exercise, and improved lifestyle can delay dementia progression and reduce the risk of AD in elderly individuals and reverse subjects with mild cognitive impairment to a non-demented state.

By-Products from Winemaking and Olive Mill Value Chains for the Enrichment of Refined Olive Oil: Technological Challenges and Nutraceutical Features

A growing body of literature is available about the valorization of food by-products to produce functional foods that combine the basic nutritional impact with the improvement of the health status of consumers. In this context, this study had two main objectives: (i) An innovative multistep extraction process for the production of a refined olive oil enriched with phenolic compounds (PE-ROO) extracted from olive pomace, olive leaves, or grape marc was presented and discussed. (ii) The most promising PE-ROOs were selected and utilized in in vitro and in vivo trials in order to determine their effectiveness in the management of high fat diet-induced-metabolic syndrome and oxidative stress in rats. The best results were obtained when olive leaves were used as source of phenols, regardless of the chemical composition of the solvent utilized for the extraction. Furthermore, while ethanol/hexane mixture was confirmed as a good solvent for the extraction of phenols compounds soluble in oil, the mix ROO/ethanol also showed a good extracting power from olive leaves. Besides, the ROO enriched with phenols extracted from olive leaves revealed an interesting beneficial effect to counteract high fat diet-induced-metabolic disorder and oxidative stress in rats, closely followed by ROO enriched by utilizing grape marc.

Racial Differences in Dietary Relations to Cognitive Decline and Alzheimer's Disease Risk: Do We Know Enough?

The elderly population in the US is increasing and projected to be 44% minority by 2060. African Americans and Hispanics are at increased risk of cognitive impairment and Alzheimer’s disease compared to non-Hispanic whites. These conditions are associated with many other adverse health outcomes, lower quality of life, and substantial economic burden. In the past few decades, diet has been identified as an important modifiable risk factor for cognitive decline and Alzheimer’s disease. Some studies report poor diet quality among African American and Hispanic older adult populations compared to their white counterparts. We have a limited understanding of how diet affects brain health in different racial-ethnic groups. One primary reason for our lack of knowledge is that most cohort studies are of majority non-Hispanic white participants. Moreover, those that do include minority participants do not publish their findings stratified by racial-ethnic groups, and likely have a less accurate measurement of dietary intake among minority groups. In this review, we summarize the current, albeit limited, literature on racial/ethnic differences in dietary relations to dementia outcomes. We will also discuss methodological issues in conducting nutrition studies in diverse cultures, and suggestions for future research directions. Overcoming the gaps will make it possible to make dietary recommendations for Alzheimer’s prevention that are more relevant for different racial/ethnic groups and set us on a faster track to reduce health disparities.

Geospatial analysis of Mediterranean diet adherence in the United States

OBJECTIVE

The current study aims to describe the Mediterranean diet (MD) adherence across the US regions, and explore the predictive factors of MD adherence among US adults.

DESIGN

Cross-sectional secondary data analysis. MD adherence score (0-9) was calculated using the Block 98 FFQ. Hot spot analysis was conducted to describe the geospatial distribution of MD adherence across the US regions. Logistic regression explored predictors of MD adherence.

SETTING

Nationwide community-dwelling residency in the USA.

PARTICIPANTS

Adults aged ≥45 years (n 20 897) who participated in the REasons for Geographic and Racial Differences in Stroke study and completed baseline assessment during January 2003 and October 2007.

RESULTS

The mean of MD adherence score was 4·36 (sd 1·70), and 46·5 % of the sample had high MD adherence (score 5-9). Higher MD adherence clusters were primarily located in the western and northeastern coastal areas of the USA, whereas lower MD adherence clusters were majorly observed in south and east-north-central regions. Being older, black, not a current smoker, having a college degree or above, an annual household income ≥ $US 75K, exercising ≥4 times/week and watching TV/video <4 h/d were each associated with higher odds of high MD adherence.

CONCLUSIONS

There were significant geospatial and population disparities in MD adherence across the US regions. Future studies are needed to explore the causes of MD adherence disparities and develop effective interventions for MD promotion in the USA.

Adherence to the Australian Dietary Guidelines Is Not Associated with Brain Structure or Cognitive Function in Older Adults

BACKGROUND

Cognitive dysfunction is common in older adults, particularly in those with type 2 diabetes (T2D). Higher adherence to the Dietary Guidelines for Americans is associated with better brain health. However, it is unclear if adherence to the Australian Dietary Guidelines (ADG) is associated with cognition or brain structure in older adults.

OBJECTIVE

The aims of this study were to 1) examine the relation between adherence to the ADG, cognition, and brain MRI and 2) determine whether T2D modifies any associations.

METHODS

The Cognition and Diabetes in Older Tasmanians Study is a cross-sectional study in 688 people (n = 343 with T2D) aged 55-90 y. A validated 80-item food-frequency questionnaire was used to assess dietary intake. Adherence to the 2013 ADG was estimated using the Dietary Guidelines Index (DGI). Cognitive function in multiple domains was assessed with a comprehensive battery of neuropsychological tests and brain structure with MRI. Multivariable linear models were used to assess the associations between DGI, cognitive z scores, and brain structure. Effect modification for T2D was examined with a DGI × T2D product term.

RESULTS

The mean age of the sample was 69.9 y (SD: 7.4 y), with 57.1% men. The mean DGI was 54.8 (SD: 10.7; range: 24.1-84.6). No associations were observed between the Australian DGI and cognition or brain MRI measures. T2D did not modify any associations (P > 0.05).

CONCLUSIONS

This is the first study to investigate associations between adherence to the ADG and brain health in the older adults with and without T2D. Future prospective studies are required to clarify if there are long-term associations.

Dietary Patterns and Cognitive Decline: key features for prevention

The decline in cognitive function is generally the result of the complex interaction of several factors. First of all, age, but also demographic, educational, genetic, socio-economic, and environmental determinants, including nutrition. Cognitive decline and dementia prevalence are increasing, and they are projected to continue increasing in the next decades due to the aging of the world population. Currently, there are no effective pharmacological treatments for these devastating and disabling conditions, which emphasize the key role of preventive strategies. There is compelling evidence of the role of diet and lifestyle on cognitive function. Therefore, dietary/ nutritional approaches that contribute to prevent, or slow cognitive decline may have a remarkable public health impact. Numerous studies have explored the role of dietary components and patterns on age-associated cognitive decline, with accruing evidence that combinations of foods and nutrients can have synergistic effects beyond those attributable to individual foods or nutrients. Dietary patterns show the strongest evidence for slowing the development of cognitive decline, Alzheimer's disease and other dementias including the Mediterranean diet, the Dietary Approaches to Stop Hypertension diet, and their combination (the MedDiet-DASH Intervention for Neurodegenerative Delay - MIND), among others with few positive results. There are also dietary patterns with no evidence of such effects. This review examines the evidence for the effects of some dietary patterns as neuroprotective with a potential to delay cognitive decline and the onset of dementia.

Consumption of fruits and vegetables: improved physical health, mental health, physical functioning and cognitive health in older adults from 11 European countries

Objective: Regular consumption of fruits and vegetables has been found to contribute to physical health and physical functioning. However, health is not limited to the absence of physical diseases but also encompasses mental health and cognition. Thus, we wanted to examine how the consumption of fruit and vegetables is associated with overall health, including mental health and cognitive health of older European adults.Design: We used multilevel regression analysis (participants nested within countries) to examine the effects of nutrition on overall health. Participants were asked in 2011 about their health behaviour including nutritional habits. Several health outcomes were measured longitudinally in 2013: Self-rated health, grip strength, instrumental activities of daily living (IADL), activities of daily living (ADL), mobility, depression, quality of life, short-term memory, and long-term memory.Setting: We used the 2011 and 2013 waves of the Survey of Health, Ageing and Retirement in Europe (SHARE), a multi-national population survey of older adults.Subjects:N = 22,635 older adults were sampled from 11 European countries.Results: Frequent consumption of fruits and vegetables is associated with improved health outcomes, including cognitive and mental health.Conclusions: Frequent consumption of fruits and vegetables contributes to slower disablement processes and might be an easily implementable way to improve the overall health of older adults. Future studies should examine the cross-national differences in the observed effects.

NUTRITIONAL RISK STATUS, DIETARY INTAKE AND COGNITIVE PERFORMANCE IN OLDER ADULTS WITH MOTORIC COGNITIVE RISK SYNDROME

Background

Modifiable lifestyle factors such as diet are associated with cognitive decline and dementia. Greater understanding of the nutritional intake of older adults who are at increased risk for cognitive decline may allow for the development of more effective dietary interventions to prevent or delay the onset of dementia.

Objectives

The purpose of this study was to characterize the nutritional status, diet quality and individual nutritional components of older adults with motoric cognitive risk syndrome (MCR). MCR is a pre-dementia syndrome classified by slow gait speed and subjective memory impairments.

Design

Cross-sectional analysis.

Setting

A community-based senior center located in an urban setting.

Participants

Twenty-five community-dwelling older adults with MCR aged 60-89 yrs.

Measurements

Nutritional risk status was determined using the Nestle Mini Nutritional Assessment (MNA). A food frequency questionnaire was used to quantify: overall dietary quality using the Healthy Eating Index (HEI); adherence to the Mediterranean-DASH for Neurodegenerative Delay (MIND) dietary pattern; and intake of individual nutritional components shown to be protective or harmful for cognitive function in older adults. Participants completed a computerized cognitive testing battery to assess cognitive abilities.

Results

More than one third (36%) of participants were at increased risk for malnutrition. Participants at lower risk for malnutrition had better working memory (r = 0.40, p = 0.04), executive functioning (r = 0.44, p = 0.03), and overall cognition (r = 0.44, p = 0.03). While participants generally consumed a reasonable quality diet (HEI = 65.15), 48% of participants had poor adherence to a neuroprotective MIND dietary pattern. Higher intake of B-complex vitamins was associated with better task switching (r = 0.40, p ≤ 0.05) and faster processing speeds (r = 0.39, p ≤ 0.05). Higher vitamin C intake was associated with better executive functioning (r = 0.40, p ≤ 0.05).

Conclusions

Our findings suggest that a significant proportion of older adults with MCR may be at increased risk for malnutrition. While the diet quality of older adults with MCR appeared to need improvement, future studies should investigate the effects of more specific nutritional interventions, including the MIND diet, on cognition in at-risk older adults.

Mediterranean Diet Adherence Modulates Anthropometric Measures by TCF7L2 Genotypes among Puerto Rican Adults

BACKGROUND

Transcription factor 7-like 2 (TCF7L2) genetic variants that predispose individuals to type 2 diabetes (T2D) show inconsistent associations with anthropometric traits. Interaction between TCF7L2 genotypes and dietary factors may help explain these observations.

OBJECTIVE

We aimed to examine the potential modulation of TCF7L2-rs7903146 and rs12255372 on anthropometric markers by a Mediterranean diet (MedDiet).

METHODS

Cross-sectional analysis was conducted in 1120 participants (aged 45-75 y) of the Boston Puerto Rican Health Study. Anthropometric variables were measured, and polymorphisms were genotyped using standardized protocols. Diet was assessed using a validated FFQ. The MedDiet was defined based on adherence to 9 food and nutrient components using sex-specific population-based median cut-offs; high adherence was defined as meeting ≥4 components. Haplotypes were tested for association with obesity traits, independently and via interaction with the MedDiet.

RESULTS

TCF7L2-rs7903146 showed significant interaction with the MedDiet influencing BMI, weight, and waist circumference. The T risk-allele carriers (CT + TT) with a high MedDiet score had lower weight (77.3 ± 1.0 compared with CC 80.9 ± 1.0 kg; P = 0.013) and waist circumference (99.2 ± 0.9 compared with CC 102.2 ± 0.9 cm; P = 0.021), when compared with CC participants. A low MedDiet score resulted in no significant differences between genotypes. For TCF7L2-rs12255372, we found significant interactions with the MedDiet for weight (P-interaction = 0.034) and BMI (P-interaction = 0.036). The T allele carriers with a higher MedDiet score showed a trend of lower but no significant differences when compared with CC participants for BMI (P = 0.19), weight (P = 0.09), and waist circumference (P = 0.11). We found significant interactions between the 2 risk-carrying haplotypes and the MedDiet compared with the common haplotype (GC), with lower BMI (β ± SE, TT: -1.53 ± 0.68; P-interaction = 0.024), weight (TT: -4.16 ± 1.77; P-interaction = 0.019), and waist circumference (GT: -5.07 ± 2.50; P-interaction = 0.042) at a high MedDiet score.

CONCLUSION

Puerto Ricans with the TCF7L2-rs7903146 and rs12255372 T2D risk genotypes, although still high, had better anthropometric profiles when adhering to a MedDiet, suggesting that this diet may offset unfavorable genetic predisposition.

Diet quality and cognitive function in mid-aged and older men and women

Background

To date much research into nutrition and cognitive function has been at the nutrient or food level, with inconsistent results. There is increasing interest in the dietary pattern approach to assess whole diet quality and its association with cognitive function. This study investigated if diet quality is associated with cognitive function in men and women aged 55 years and over.

Methods

Adults aged 55–65 years in the Wellbeing, Eating and Exercise for a Long Life (WELL) study in Victoria, Australia (n = 617) completed a postal survey including a 111-item food frequency questionnaire in 2010 and 2014. Diet quality was assessed via the revised dietary guideline index (DGI-2013) and also by its individual components which assessed key food groups and dietary behaviours from the Australian Dietary Guidelines. The Telephone Interview of Cognitive Status (TICS-m) measured cognitive function in 2014. Associations between past (2010) and recent (2014) diet quality and its components, and cognitive function were assessed by linear regression adjusted for covariates.

Results

After adjustment for age, sex, education, urban/rural status and physical activity there were no associations between diet quality in 2010 and cognitive function in 2014. However participants who reported higher dietary variety (B = 0.28, 95% CI 0.03, 0.52) and women who reported “sometimes” adding salt to food after cooking (B = 0.98, 95% CI 0.25, 1.71) in 2010 displayed better cognitive function in 2014. In 2014, usual consumption of higher fibre bread choices in the total sample (B = 1.32, 95% CI 0.42, 2.23), and higher diet quality (B = 0.03, 95% CI 0.00, 0.07) and greater fluid consumption (B = 0.14, 95% CI 0.01, 0.27) in men were all associated with better cognitive function. In addition, men who reported “usually” adding salt to their food during cooking displayed poorer cognitive function (B = -1.37, 95% CI -2.39, − 0.35). There were no other associations between dietary intake and cognitive function observed in the adjusted models.

Conclusion

An association between dietary variety and some limited dietary behaviours and cognitive function was observed, with variation by gender. Future research should consider trajectories of dietary change over longer time periods as determinants of health and function in older age.

Effect of nutrition on neurodegenerative diseases. A systematic review

Neurodegenerative diseases are characterized by the progressive functional loss of neurons in the brain, causing cognitive impairment and motoneuron disability. Although multifactorial interactions are evident, nutrition plays an essential role in the pathogenesis and evolution of these diseases. A systematic literature search was performed, and the prevalence of studies evaluated the effect of the Mediterranean diet (MeDiet), nutritional support, EPA and DHA, and vitamins on memory and cognition impairment. The data showed that malnutrition and low body mass index (BMI) is correlated with the higher development of dementia and mortality. MeDiet, nutritional support, and calorie-controlled diets play a protective effect against cognitive decline, Alzheimer's disease (AD), Parkinson disease (PD) while malnutrition and insulin resistance represent significant risk factors. Malnutrition activates also the gut-microbiota-brain axis dysfunction that exacerbate neurogenerative process. Omega-3 and -6, and the vitamins supplementation seem to be less effective in protecting neuron degeneration. Insulin activity is a prevalent factor contributing to brain health while malnutrition correlated with the higher development of dementia and mortality.

The Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) Diets Are Associated with Less Cognitive Decline and a Lower Risk of Alzheimer's Disease-A Review

As there is currently no cure for dementia, there is an urgent need for preventive strategies. The current review provides an overview of the existing evidence examining the associations of the Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets and their dietary components with cognitive decline, dementia, and Alzheimer's disease (AD). A systematic search was conducted within Ovid Medline for studies published up to 27 March 2019 and reference lists from existing reviews and select articles were examined to supplement the electronic search results. In total, 56 articles were included. Higher adherence to the Mediterranean diet was associated with better cognitive scores in 9 of 12 cross-sectional studies, 17 of 25 longitudinal studies, and 1 of 3 trials. Higher adherence to the DASH diet was associated with better cognitive function in 1 cross-sectional study, 2 of 5 longitudinal studies, and 1 trial. Higher adherence to the MIND diet was associated with better cognitive scores in 1 cross-sectional study and 2 of 3 longitudinal studies. Evidence on the association of these dietary patterns with dementia in general was limited. However, higher adherence to the Mediterranean diet was associated with a lower risk of AD in 1 case-control study and 6 of 8 longitudinal studies. Moreover, higher adherence to the DASH or MIND diets was associated with a lower AD risk in 1 longitudinal study. With respect to the components of these dietary patterns, olive oil may be associated with less cognitive decline. In conclusion, current scientific evidence suggests that higher adherence to the Mediterranean, DASH, or MIND diets is associated with less cognitive decline and a lower risk of AD, where the strongest associations are observed for the MIND diet.

Mediterranean diet adherence and cognitive function in older UK adults: the European Prospective Investigation into Cancer and Nutrition-Norfolk (EPIC-Norfolk) Study

BACKGROUND

In Mediterranean countries, adherence to a traditional Mediterranean dietary pattern (MedDiet) is associated with better cognitive function and reduced dementia risk. It is unclear if similar benefits exist in non-Mediterranean regions.

OBJECTIVES

The aims of this study were to examine associations between MedDiet adherence and cognitive function in an older UK population and to investigate whether associations differed between individuals with high compared with low cardiovascular disease (CVD) risk.

METHODS

We conducted an analysis in 8009 older individuals with dietary data at Health Check 1 (1993-1997) and cognitive function data at Health Check 3 (2006-2011) of the European Prospective Investigation into Cancer and Nutrition-Norfolk (EPIC-Norfolk). Associations were explored between MedDiet adherence and global and domain-specific cognitive test scores and risk of poor cognitive performance in the entire cohort, and when stratified according to CVD risk status.

RESULTS

Higher MedDiet adherence defined by the Pyramid MedDiet score was associated with better global cognition (β ± SE = -0.012 ± 0.002; P < 0.001), verbal episodic memory (β ± SE = -0.009 ± 0.002; P < 0.001), and simple processing speed (β ± SE = -0.002 ± 0.001; P = 0.013). Lower risk of poor verbal episodic memory (OR: 0.784; 95% CI: 0.641, 0.959; P = 0.018), complex processing speed (OR: 0.739; 95% CI: 0.601, 0.907; P = 0.004), and prospective memory (OR: 0.841; 95% CI: 0.724, 0.977; P = 0.023) was also observed for the highest compared with the lowest Pyramid MedDiet tertiles. The effect of a 1-point increase in Pyramid score on global cognitive function was equivalent to 1.7 fewer years of cognitive aging. MedDiet adherence defined by the Mediterranean Diet Adherence Screener (MEDAS) score (mapped through the use of both binary and continuous scoring) showed similar, albeit less consistent, associations. In stratified analyses, associations were evident in individuals at higher CVD risk only (P < 0.05).

CONCLUSIONS

Higher adherence to the MedDiet is associated with better cognitive function and lower risk of poor cognition in older UK adults. This evidence underpins the development of interventions to enhance MedDiet adherence, particularly in individuals at higher CVD risk, aiming to reduce the risk of age-related cognitive decline in non-Mediterranean populations.

The Interplay of Diet Quality and Alzheimer's Disease Genetic Risk Score in Relation to Cognitive Performance Among Urban African Americans

We examined the interactive associations of poor diet quality and Alzheimer’s Disease (AD) genetic risk with cognitive performance among 304 African American adults (mean age~57 years) from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. In this cross-sectional study, selected participants had complete predictors and covariate data with 13 cognitive test scores as outcomes. Healthy Eating Index-2010 (HEI-2010), Dietary Approaches to Stop Hypertension (DASH), and mean adequacy ratio (MAR) were measured. A genetic risk score for AD in HANDLS (hAlzScore) was computed from 12 selected single nucleotide polymorphisms (SNPs). Our key hypotheses were tested using linear regression models. The hAlzScore was directly associated with poor performance in verbal memory (−0.4 ± 0.2, 0.01) and immediate visual memory (0.4 ± 0.2, 0.03) measured in seconds, in women only. The hAlzScore interacted synergistically with poorer diet quality to determine lower cognitive performance on a test of verbal fluency. Among numerous SNP × diet quality interactions for models of cognitive performance as outcomes, only one passed correction for multiple testing, namely verbal fluency. Our results suggest that improved diet quality can potentially modify performance on cognitive tests of verbal fluency among individuals with higher AD genetic risk.

The Mediterranean Diet and 2-Year Change in Cognitive Function by Status of Type 2 Diabetes and Glycemic Control

OBJECTIVE

To determine associations of a Mediterranean diet score (MeDS) with 2-year change in cognitive function by type 2 diabetes and glycemic control status and contrast it against other diet quality scores.

RESEARCH DESIGN AND METHODS

We used data from the longitudinal Boston Puerto Rican Health Study (n = 913; 42.6% with type 2 diabetes at 2 years). Glycemic control at baseline was categorized as uncontrolled (hemoglobin A1c ≥7% [53 mmol/mol]) versus controlled. Two-year change in glycemic control was defined as stable/improved versus poor/declined. We defined MeDS, Healthy Eating Index, Alternate Healthy Eating Index, and Dietary Approaches to Stop Hypertension scores. Adjusted mixed linear models assessed 2-year change in global cognitive function z score, executive and memory function, and nine individual cognitive tests.

RESULTS

Higher MeDS, but no other diet quality score, was associated with higher 2-year change in global cognitive function in adults with type 2 diabetes (β ± SE = 0.027 ± 0.011; P = 0.016) but not in those without (P = 0.80). Similar results were noted for Mini-Mental State Examination, word recognition, digit span, and clock drawing tests. Results remained consistent for individuals under glycemic control at baseline (0.062 ± 0.020; P = 0.004) and stable/improved over 2 years (0.053 ± 0.019; P = 0.007), but not for individuals with uncontrolled or poor/declined glycemic control. All diet quality scores were associated with higher 2-year memory function in adults without type 2 diabetes.

CONCLUSIONS

Both adhering to a Mediterranean diet and effectively managing type 2 diabetes may support optimal cognitive function. Healthy diets, in general, can help improve memory function among adults without type 2 diabetes.

Mediterranean Diet in Preventing Neurodegenerative Diseases

PURPOSE OF REVIEW

We reviewed the most recent literature examining the associations between the Mediterranean-style diet (MD), neurodegenerative diseases, and markers and mechanisms of neurodegeneration.

RECENT FINDINGS

Most, but not all, epidemiologic studies report a protective association between MD adherence, cognitive impairment, and brain health. Data from clinical trials supporting these observational findings are also emerging. Limited evidence suggests that MD adherence may be protective for Parkinson's disease risk. Mechanistically, plant polyphenols may activate similar molecular pathways as caloric restriction diets, which helps explain the neuroprotective properties of the MD. Evidence for cognitive disorders is abundant, but there is a dearth of literature for other neurodegenerative disorders and for markers of neurodegeneration. Further research is needed to elucidate the protective role of MD on neurodegeneration, the most salient components of the MD, and the most sensitive time periods over the lifecourse at which the MD may exert its effects.

A systematic review of existing peripheral biomarkers of cognitive aging: Is there enough evidence for biomarker proxies in behavioral modification interventions?: An initiative in association with the nutrition, exercise and lifestyle team of the Canadian Consortium on Neurodegeneration in Aging

Peripheral biomarkers have shown significant value in predicting brain health and may serve as a useful proxy measurement in the assessment of evidence-based lifestyle behavior modification programs, including physical activity and nutrition programs, that aim to maintain cognitive function in late life. The aim of this systematic review was to elucidate which peripheral biomarkers are robustly associated with cognitive function among relatively healthy non-demented older adults. Following the standards for systematic reviews (PICO, PRIMSA), and employing MEDLINE and Scopus search engines, 222 articles were included in the review. Based on the review of biomarker proxies of cognitive health, it is recommended that a comprehensive biomarker panel, or biomarker signature, be developed as a clinical end point for behavior modification trials aimed at enhancing cognitive function in late life. The biomarker signature should take a multisystemic approach, including lipid, immune/inflammatory, and metabolic biomarkers in the biological signature index of cognitive health.

Lower Plasma Vitamin B-6 is Associated with 2-Year Cognitive Decline in the Boston Puerto Rican Health Study

BACKGROUND

Despite its important role in cognitive development and regulation of nervous system function, vitamin B-6 has been under-studied in relation to cognitive aging.

OBJECTIVE

We investigated whether plasma pyridoxal-5'-phosphate (PLP, vitamin B-6) concentrations were associated with cognitive function and subsequent cognitive decline.

METHODS

In a longitudinal study of 949 participants (aged 45-75 y at baseline; 70% women) from the Boston Puerto Rican Health Study cohort, we examined the association between baseline plasma PLP and baseline cognitive function and 2-y cognitive decline. Cognitive function was assessed with an in-person 7-test cognitive battery, at baseline and 2-y follow-up. We also used logistic regression to estimate the odds of major 2-y decline in global cognitive function (defined as decline ≥1 SD below the mean), as well as decline in executive function and memory. We also used multivariable linear regression to calculate adjusted mean differences in cognitive scores, and 95% CIs, across tertiles of plasma PLP at baseline, as well as cross-sectional and longitudinal associations with individual test scores.

RESULTS

In analyses adjusted for potential confounders, the OR of having a major 2-y decline in global cognitive function was 2.46 (95% CI: 1.49, 4.05; P-trend: 0.001) among participants in the lowest tertile of PLP compared with those in the top tertile of PLP. The association of PLP with cognition was stronger in participants older than 55 y at baseline (OR for bottom to top tertile: 4.58; 95% CI: 2.02, 10.35; P-interaction: 0.01) compared with those 55 y old or younger, as well as in ever smokers (OR for bottom to top tertile: 2.99; 95% CI: 1.45, 6.19; P-interaction: 0.02) compared with never smokers.

CONCLUSIONS

Lower baseline plasma PLP was associated with increased odds of 2-y cognitive decline in a cohort of Boston area Puerto Ricans. The association was stronger among older participants and among ever smokers.

Serum vitamin D and cognition in a cohort of Boston-area Puerto Ricans

Background: Vitamin D has been suggested as a protective factor for cognitive health, however results of prior studies have been mixed. To examine whether serum 25(OH)D concentration is related to cognition and cognitive decline in a study of Boston Area Puerto Ricans. Methods: We examined the association between serum 25(OH)D, cognitive function and cognitive decline in a longitudinal study of 967 Boston Area Puerto Rican adults. Results: In analyses adjusted for potential confounders, participants in the bottom quintile of 25(OH)D had similar cognitive function at baseline, as measured by a global cognitive score (mean difference: 0.09 (95% CI: -0.02, 0.19); p-trend: 0.18), and similar 2-year rates of cognitive decline (mean difference: -0.01 (95% CI: -0.09, 0.07), p-trend: 0.61) as those in the top 25(OH)D quintile. No significant associations were observed between baseline serum 25(OH)D concentration and 2-year change in individual cognitive test scores or change in executive function or memory domains. Conclusions: We observed no significant association between serum 25(OH)D and cognition in this cohort of Boston Area Puerto Ricans.

Dietary Acculturation among Puerto Rican Adults Varies by Acculturation Construct and Dietary Measure

Background

The role of acculturation in dietary behaviors among Hispanics/Latinos in the United States remains unclear. Discrepancies may be explained by variations in acculturation constructs or ethnicity-specific dynamics.

Objective

We aimed to compare relations between 3 different acculturation constructs with dietary quality and patterns among Puerto Ricans in the mainland United States.

Methods

We analyzed cross-sectional data with 1194-1380 Puerto Ricans, aged 45-75 y. Acculturation was measured with the use of a language-based scale (0-100; higher score denotes more English use), a psychological-based scale (0-50; higher score denotes stronger US orientation), and years living in the mainland United States. Diet quality scores (higher scores denote healthier diet) were defined with the use of the Alternate Healthy Eating Index-2010 (AHEI) and the Mediterranean Diet Score (MeDS). Three dietary patterns were previously derived with the use of principal components analysis. Adjusted multivariable regression models tested the association of each acculturation construct with diet quality score or pattern. Interaction terms were included for income or education status.

Results

Psychological-based acculturation, but not the other constructs, was positively associated with AHEI (β ± SE: 0.013 ± 0.004; P = 0.002) and MeDS (0.009 ± 0.005; P = 0.041). Income, but not education, moderated this association (P = 0.03), with higher diet quality observed with higher income (>$25,000) and stronger US orientation. All constructs were inversely associated with a traditional dietary pattern, with the language-based scale being stronger (z score β ± SE: -0.160 ± 0.032; P < 0.0001) than the psychological-based scale (-0.097 ± 0.028; P = 0.001) or years living in the mainland United States (-0.058 ± 0.028; P = 0.041). No associations were observed for the Western or sweets/desserts patterns.

Conclusions

In Puerto Rican adults, stronger psychological US orientation was associated with higher diet quality, particularly with higher income. More Spanish use, stronger psychological Puerto Rican orientation, and shorter length of mainland-US residency were associated with traditional dietary patterns. Appropriate diet-related acculturation constructs should be carefully considered among Hispanics/Latinos. This trial was registered at clinicaltrials.gov as NCT01231958.

Food Insecurity and Odds of High Allostatic Load in Puerto Rican Adults: The Role of Participation in the Supplemental Nutrition Assistance Program During 5 Years of Follow-Up

OBJECTIVE

Limited evidence demonstrates pathways linking food insecurity (FI) to chronic disease. Allostatic load (AL) may elucidate potential pathways, capturing both primary (neuroendocrine, inflammation) and secondary (metabolic, cardiovascular) physiological disturbances. We examined the longitudinal association of FI with 5-year AL and primary and secondary subsystem dysregulation and tested moderation by Supplemental Nutrition Assistance Program (SNAP) participation.

METHODS

We analyzed data from the longitudinal Boston Puerto Rican Health Study among 733 adults aged 45 to 75 years. Participants categorized as food insecure (assessed by US survey module) experienced FI at baseline and/or year 5. AL score comprised 11 biological components (5 primary, 6 secondary). We classified participants as having high scores for AL (≥6 dysregulated components), primary system (≥3), and secondary system (≥4). Multivariate models estimated odds ratios (OR), adjusting for baseline AL, sociodemographic, cultural, and behavioral characteristics.

RESULTS

By study end, 33.8% had experienced FI, 65.5% had participated in SNAP, and 37.5% had high AL. In adjusted models, FI was not associated with AL (OR [95% confidence intervals] = 1.07 [0.70-1.64]) or secondary system (0.82 [0.48-1.40]) scores, but was associated with high primary system scores (1.71 [1.25-2.36]). SNAP participation seemed to moderate the FI-primary system relationship (p = .06); food-insecure participants never receiving SNAP (mean (SE) = 2.06 (0.14)) had higher scores than food-secure participants receiving (1.72 (0.06], p = .02) or never receiving SNAP (1.64 (0.10), p = .01) and food-insecure participants receiving SNAP (1.80 (0.07), p = .08).

CONCLUSIONS

FI is associated with dysregulated components of the primary AL system, and this relationship may be stronger for those not receiving SNAP. Research is needed in additional populations to test AL as a plausible pathway connecting FI to chronic disease and SNAP as a moderator.

Prospective Associations of Erythrocyte Composition and Dietary Intake of n-3 and n-6 PUFA with Measures of Cognitive Function

Polyunsaturated fatty acid (PUFA) consumption is recommended as part of a healthy diet, but evidence of the impact of individual species and biological concentrations on cognitive function is limited. We examined prospective associations of PUFA erythrocyte composition and dietary intake with measures of cognitive function among participants of the Boston Puerto Rican Health Study (aged 57 years). Erythrocyte and dietary PUFA composition were ascertained at baseline and associated with 2-year scores on the Mini-Mental State Exam (MMSE) (n = 1032) and cognitive domain patterns derived from a battery of tests (n = 865), as well as with incidence of cognitive impairment. Erythrocyte and dietary n-3 PUFA were not significantly associated with MMSE score. However, total erythrocyte and dietary n-3 very-long-chain fatty acids (VLCFA), and intake of individual species, were associated with better executive function (P-trend < 0.05, for all). There was evidence that greater erythrocyte n-6 eicosadienoic acid concentration was associated with lower MMSE and executive function scores (P-trend = 0.02). Only erythrocyte arachidonic acid (ARA) concentration predicted cognitive impairment (Odds Ratio = 1.26; P = 0.01). Among Puerto Rican adults, we found that n-3 VLCFA consumption may beneficially impact executive function. Further, these findings provide some evidence that n-6 metabolism favoring greater ARA tissue incorporation, but not necessarily dietary intake, could increase the risk of cognitive impairment.

Hidden Hunger: Solutions for America's Aging Populations

The global population, including the United States, is experiencing a demographic shift with the proportion of older adults (aged ≥ 65 years) growing faster than any other age group. This demographic group is at higher risk for developing nutrition-related chronic conditions such as heart disease and diabetes as well as infections such as influenza and pneumonia. As a result, an emphasis on nutrition is instrumental for disease risk reduction. Unfortunately, inadequate nutrient status or deficiency, often termed hidden hunger, disproportionately affects older adults because of systematic healthcare, environmental, and biological challenges. This report summarizes the unique nutrition challenges facing the aging population and identifies strategies, interventions, and policies to address hidden hunger among the older adults, discussed at the scientific symposium "Hidden Hunger: Solutions for America's Aging Population", on March 23, 2018.

Dietary Patterns and Cognitive Function among Older Community-Dwelling Adults

Diet may be an important modifiable risk factor for maintenance of cognitive health in later life. This study aimed at examining associations between common dietary indices and dietary patterns defined by factor analysis and cognitive function in older community-dwelling adults. Dietary information for 1499 participants from the Rancho Bernardo Study was collected in 1988–1992 and used to calculate the alternate Mediterranean diet score, Alternate Healthy Eating Index (AHEI)-2010 score and factor scores derived from factor analysis of nutrients. Global cognitive function, executive function, verbal fluency and episodic memory were assessed at approximate four-year intervals from 1988–2016. Linear mixed models were used to examine associations between dietary patterns and cognitive trajectories. Estimates for the highest vs. lowest tertile in models adjusting for age, sex, education, energy intake, lifestyle variables and retest effect showed greater adherence to the Mediterranean score was associated with better baseline global cognitive function (β (95% CI) = 0.33 (0.11, 0.55)). The AHEI-2010 score was not significantly associated with cognitive performance. Higher loading on a plant polyunsaturated fatty acid (PUFA)/vitamin E factor was associated with better baseline global cognitive function and executive function (β = 0.22 (0.02, 0.42) and β = −7.85 (−13.20, −2.47)). A sugar/low protein factor was associated with poorer baseline cognitive function across multiple domains. Dietary patterns were not associated with cognitive decline over time. Adherence to a healthy diet with foods high in PUFA and vitamin E and a low sugar to protein ratio, as typified by a Mediterranean diet, may be beneficial for cognitive health in late life.

Mediterranean Diet and Cardiometabolic Diseases in Racial/Ethnic Minority Populations in the United States

The Mediterranean diet (MedDiet) has been recommended to the general population by many scientific organizations as a healthy dietary pattern, based on strong evidence of association with improved cardiometabolic health, including lower risk of cardiovascular disease, diabetes, and obesity. However, most studies have been conducted in Mediterranean or European countries or among white populations in the United States (US), while few exist for non-Mediterranean countries or racial/ethnic minority populations in the US. Because most existing studies evaluating adherence to the MedDiet use population-specific definitions or scores, the reported associations may not necessarily apply to other racial/ethnic populations that may have different distributions of intake. Moreover, racial/ethnic groups may have diets that do not comprise the typical Mediterranean foods captured by these scores. Thus, there is a need to determine if similar positive effects from following a MedDiet are observed in diverse populations, as well as to identify culturally-relevant foods reflected within Mediterranean-like patterns, that can facilitate implementation and promotion of such among broader racial/ethnic groups. In this narrative review, we summarize and discuss the evidence from observational and intervention studies on the MedDiet and cardiometabolic diseases in racial/ethnic minority populations in the US, and offer recommendations to enhance research on MedDiet for such populations.

The relationship between obesity and cognitive health and decline

The relationship between obesity and cognitive impairment is important given the globally ageing population in whom cognitive decline and neurodegenerative disorders will carry grave individual, societal and financial burdens. This review examines the evidence for the link between obesity and cognitive function in terms of both the immediate effects on cognitive performance, and effects on the trajectory of cognitive ageing and likelihood of dementia. In mid-life, there is a strong association between obesity and impaired cognitive function. Anthropometric measures of obesity are also associated with reduced neural integrity (e.g. grey and white matter atrophy). Increasing age coupled with the negative metabolic consequences of obesity (e.g. type 2 diabetes mellitus) are likely to significantly contribute to cognitive decline and incidence of dementia. Stress is identified as a potential risk factor promoting abdominal obesity and contributing to impaired cognitive function. However, the potentially protective effects of obesity against cognitive decline in older age require further examination. Finally, surgical and whole diet interventions, which address obesity may improve cognitive capacity and confer some protection against later cognitive decline. In conclusion, obesity and its comorbidities are associated with impaired cognitive performance, accelerated cognitive decline and neurodegenerative pathologies such as dementia in later life. Interventions targeting mid-life obesity may prove beneficial in reducing the cognitive risks associated with obesity.

Diet quality is associated with reduced incidence of cancer and self-reported chronic disease: Observations from Alberta's Tomorrow Project

The objective of this study was to assess diet quality using the Healthy Eating Index-2005 Canada (HEI-2005-Canada) and its association with risk of cancer and chronic disease in a sample of Alberta's Tomorrow Project (ATP) participants. Food frequency questionnaires completed by 25,169 participants (38% men; mean age 50.3 (9.2)) enrolled between 2000 and 2008 were used to calculate HEI-2005-Canada scores. Data from a subset of participants (n=10,735) who reported no chronic disease at enrollment were used to investigate the association between HEI-2005-Canada score and development of self-reported chronic disease at follow-up (2008). Participants were divided into HEI-2005-Canada score quartiles. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for cancer and chronic disease incidence. In this cohort, mean HEI-2005-Canada scores for men and women were 50.9 and 55.5 (maximum range 0-100), respectively. In men, higher HEI-2005-Canada score (Q4 vs. Q1) was associated with lower cancer risk (HR (95% CI) 0.63 (0.49-0.83)) over the course of follow-up (mean (SD)=10.4 (2.3) years); the same was not observed in women. In contrast, higher overall HEI-2005-Canada score (Q4 vs. Q1) was associated with lower risk of self-reported chronic disease (0.85 (0.75-0.97)) in both men and women over follow-up (4.2 (2.3) years). In conclusion, in this cohort better diet quality was associated with a lower risk of cancer in men and lower risk of chronic disease in both sexes. Future studies with longer follow-up and repeated measures of diet may be helpful to elucidate sex-specific associations between dietary quality and disease outcomes.

The Association between the Mediterranean Dietary Pattern and Cognitive Health: A Systematic Review

The ageing population is accompanied by increased rates of cognitive decline and dementia. Not only does cognitive decline have a profound impact on an individual's health and quality of life, but also on that of their caregivers. The Mediterranean diet (MD) has been known to aid in reducing the risk of cardiovascular diseases, cancer and diabetes. It has been recently linked to better cognitive function in the elderly population. The purpose of this review was to compile evidence based data that examined the effect of adherence to the MD on cognitive function and the risk of developing dementia or Alzheimer's disease. This review followed PRISMA guidelines and was conducted using four databases and resulted in 31 articles of interest. Cross-sectional studies and cohort studies in the non-Mediterranean region showed mixed results. However, cohort studies in the Mediterranean region and randomized controlled trials showed more cohesive outcomes of the beneficial effect of the MD on cognitive function. Although more standardized and in-depth studies are needed to strengthen the existing body of evidence, results from this review indicate that the Mediterranean diet could play a major role in cognitive health and risk of Alzheimer's disease and dementia.

Association of Adherence to a Healthy Diet with Cognitive Decline in European and American Older Adults: A Meta-Analysis within the CHANCES Consortium

AIM

To examine the association between a healthy diet, assessed by the Healthy Diet Indicator (HDI), and cognitive decline in older adults.

METHODS

Data from 21,837 participants aged ≥55 years from 3 cohorts (Survey in Europe on Nutrition and the Elderly, a Concerted Action [SENECA], Rotterdam Study [RS], Nurses' Health Study [NHS]) were analyzed. HDI scores were based on intakes of saturated fatty acids, polyunsaturated fatty acids, mono- and disaccharides, protein, cholesterol, fruits and vegetables, and fiber. The Telephone Interview for Cognitive Status in NHS and Mini-Mental State Examination in RS and SENECA were used to assess cognitive function from multiple repeated measures. Using multivariable-adjusted, mixed linear regression, mean differences in annual rates of cognitive decline by HDI quintiles were estimated.

RESULTS

Multivariable-adjusted differences in rates in the highest versus the lowest HDI quintile were 0.01 (95% CI -0.01, 0.02) in NHS, 0.00 (95% CI -0.02, 0.01) in RS, and 0.00 (95% CI -0.05, 0.05) in SENECA with a pooled estimate of 0.00 (95% CI -0.01, 0.01), I2 = 0%.

CONCLUSIONS

A higher HDI score was not related to reduced rates of cognitive decline in European and American older adults.

Comparison of Dietary Quality Among Puerto Ricans Living in Massachusetts and Puerto Rico

Puerto Ricans are burdened by nutrition-related diseases, with greater disease prevalence among Puerto Ricans residing in the continental U.S. compared to those in Puerto Rico (PR). However, little is known about diet quality of these two groups. To compare diet quality of Puerto Ricans in Massachusetts (MA) and PR. Puerto Rican patients from health centers in MA (n = 42) and PR (n = 52) completed a food frequency questionnaire. Diet quality was assessed with the Healthy Eating Index-2010 (HEI). Analysis included Mann-Whitney, Chi square and logistic and quantile regressions. 57.1 % of participants in MA and 19.6 % in PR had a poor diet. Adjusting for age and education, participants in MA were more likely to have a poor diet (OR 3.4; p = 0.02) and lower HEI scores than participants in PR. Diet quality among Puerto Ricans is poor, and is worse among mainland Puerto Ricans compared to islanders.