ABSTRACT
Healthy dietary patterns such as the Mediterranean diet (MeDi), Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) have been evaluated for their potential association with health outcomes. However, the lack of standardisation in scoring methodologies can hinder reproducibility and meaningful cross-study comparisons. Here we provide a reproducible workflow for generating the MeDi, DASH and MIND dietary pattern scores from frequently used dietary assessment tools including the 24-h recall tool and two variations of FFQ. Subjective aspects of the scoring process are highlighted and have led to a recommended reporting checklist. This checklist enables standardised reporting with sufficient detail to enhance the reproducibility and comparability of their outcomes. In addition to these aims, valuable insights in the strengths and limitations of each assessment tool for scoring the MeDi, DASH and MIND diet can be utilised by researchers and clinicians to determine which dietary assessment tool best meets their needs.
Subject(s)
Diet, Healthy , Dietary Approaches To Stop Hypertension , Mental Recall , Humans , Diet Surveys/standards , Diet Surveys/methods , Diet, Mediterranean , Dietary Approaches To Stop Hypertension/methods , Dietary Patterns , Reproducibility of Results , Surveys and Questionnaires , WorkflowABSTRACT
Inflammation is repressed by interleukin 10 (IL10), a potent anti-inflammatory cytokine, and unchecked inflammation can have detrimental effects on cognition. In healthy older adults enrolled in the Australian Research Council Longevity Intervention (ARCLI) cohort we explored whether a known functional single nucleotide polymorphism (SNP) in the promoter region of IL10, -1082 G/A (rs1800896), was associated with reaction times on computerized cognitive testing that included elements of processing speed (i.e., reaction time). Participants were aged 60-75 years (240 females, 158 males), free of dementia and psychiatric disorders, and provide a blood sample. Processing speed was measured using the Swinburne University Computerized Cognitive Assessment Battery (SUCCAB), which includes measures of reaction time (in milliseconds, ms) on six tasks. Blood-derived DNA was genotyped for the IL10 rs1800896 SNP and presence of the APOE E4 allele. General linear models for each SUCCAB subtest were fitted, with age, sex, education (years), APOE E4 carrier status, and IL10 genotype as independent variables. Carriers of the IL10 AA genotype had significantly slower reaction times on multiple tests compared to carriers of the minor allele (AG, GG) and lower IL10 serum levels. Although IL10 SNPs have not been detected in Alzheimer's disease genome-wide associated studies, these results support further exploration of IL10 mechanisms as a possible resilience factor.
Subject(s)
Interleukin-10 , Processing Speed , Male , Female , Humans , Aged , Interleukin-10/genetics , Independent Living , Australia , Polymorphism, Single Nucleotide/genetics , Genotype , Promoter Regions, Genetic/genetics , Inflammation/genetics , Apolipoproteins E/genetics , Genetic Predisposition to DiseaseABSTRACT
BACKGROUND: Several clinical trials have examined diet and physical activity lifestyle changes as mitigation strategies for risk factors linked to cognitive decline and dementias such as Alzheimer's disease. However, the ability to modify these behaviors longer term, to impact cognitive health has remained elusive. OBJECTIVE: The MedWalk trial's primary aim is to investigate whether longer-term adherence to a Mediterranean-style diet and regular walking, delivered through motivational interviewing and cognitive-behavioral therapy (MI-CBT), can reduce age-associated cognitive decline and other dementia risk factors in older, independently living individuals without cognitive impairment. METHODS: MedWalk, a one-year cluster-randomized controlled trial across two Australian states, recruited 60-90-year-old people from independent living retirement villages and the wider community. Participants were assigned to either the MedWalk intervention or a control group (maintaining their usual diet and physical activity). The primary outcome is 12-month change in visual memory and learning assessed from errors on the Paired Associates Learning Task of the Cambridge Neuropsychological Test Automated Battery. Secondary outcomes include cognition, mood, cardiovascular function, biomarkers related to nutrient status and cognitive decline, MI-CBT effectiveness, Mediterranean diet adherence, physical activity, quality of life, cost-effectiveness, and health economic evaluation.Progress and Discussion:Although COVID-19 impacts over two years necessitated a reduced timeline and sample size, MedWalk retains sufficient power to address its aims and hypotheses. Baseline testing has been completed with 157 participants, who will be followed over 12 months. If successful, MedWalk will inform interventions that could substantially reduce dementia incidence and ameliorate cognitive decline in the community. TRIAL REGISTRATION: Registered on the Australia New Zealand Clinical Trials Registry ANZCTR 12620000978965 (https://www.anzctr.org.au).
Subject(s)
COVID-19 , Cognitive Dysfunction , Dementia , Diet, Mediterranean , Humans , Aged , Aged, 80 and over , Quality of Life , Australia/epidemiology , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/prevention & control , Walking , Cognition , Dementia/epidemiology , Dementia/prevention & control , Randomized Controlled Trials as TopicABSTRACT
The use of omega-3 polyunsaturated fatty acid (ω-3 PUFA) supplements is increasingly common among middle-aged and older adults. Users of ω-3 PUFA supplements often report using such supplements to support cognitive health, despite mixed findings reported within the ω-3 PUFA literature. To date, very few studies have explored cognitive effects in distinctly middle-aged (40 to 60 years) adults, and none have examined the acute effects (in the hours following a single dose) on cognitive performance. The current study evaluated whether a single dose of ω-3 PUFA (4020 mg docosahexaenoic acid and 720 mg eicosapentaenoic acid) influences cognitive performance and cardiovascular function in middle-aged males. Cognitive performance and cardiovascular function were assessed before and 3.5-4 h after consumption of a high dose of ω-3 PUFA (DHA + EPA) or placebo, incorporated into a standardized meal (i.e., single serve of Greek yogurt). In this study of middle-aged males, no significant differential treatment effects were observed for cognitive performance. However, a significant reduction in aortic systolic blood pressure (pre-dose to post-dose) was apparent following consumption of the ω-3 PUFA (DHA + EPA) treatment (mean difference = -4.11 mmHg, p = 0.004) but not placebo (mean difference = -1.39 mmHg, p = 0.122). Future replication in a sample comprising females, as well as patients with hypertension, is merited.
Subject(s)
Docosahexaenoic Acids , Fatty Acids, Omega-3 , Humans , Male , Middle Aged , Blood Pressure , Cognition , Docosahexaenoic Acids/pharmacology , Fatty Acids, Omega-3/pharmacology , Pilot Projects , Powders , AdultABSTRACT
INTRODUCTION: Early identification and management of physical and mental illness is vital to maintain quality of life as we age. Markers of peripheral inflammation and liver function show elevations with aging, and are also associated with depression symptoms, suggesting a similar pattern in both aging and clinical groups. METHODS: The current study examined the relationship between such markers and measures of depression/negative mood in 284 healthy older adults using data from the Australian Research Council Longevity Intervention (ARCLI). Baseline data in adults aged 60-75 included mood symptoms via Profile of Mood States and Beck Depression Inventory II, and peripheral inflammatory (TNF-α, IL-6, hs-CRP) and liver markers (GGT, ALT, AST, AST:ALT ratio) derived from blood samples. RESULTS: The inflammation and liver enzyme relationship significantly predicted mood symptoms scores. Results showed that a significant relationship between C-reactive protein (CRP) and negative mood scores on Total Mood Disturbance and four of the six subscales (all p < .01) was dependent upon higher levels of gamma-glutamyl transferase (GGT). DISCUSSION: Higher levels of normal-range liver metabolic and peripheral inflammatory markers are observed with negative mood in a healthy older sample experiencing the biological impact of aging, but in the absence of clinical depression symptoms, suggesting a possible role of oxidative stress or other biological mechanisms occurring with aging in depression etiology. Lifestyle interventions are discussed.
Subject(s)
Depression , Quality of Life , Humans , Aged , Australia , Liver/metabolism , Biomarkers , Inflammation/metabolism , C-Reactive Protein/analysis , gamma-GlutamyltransferaseABSTRACT
[This corrects the article DOI: 10.3389/fnut.2022.862475.].
ABSTRACT
BACKGROUND: As the global population ages, there has been a growing incidence of neurodegenerative diseases such as Alzheimer's. More recently, studies exploring the relationship between dietary patterns and neuroimaging outcomes have received particular attention. This systematic literature review provides a structured overview of the association between dietary and nutrient patterns on neuroimaging outcomes and cognitive markers in middle-aged to older adults. A comprehensive literature search was conducted to find relevant articles published from 1999 to date using the following databases Ovid MEDLINE, Embase, PubMed, Scopus and Web of Science. The inclusion criteria for the articles comprised studies reporting on the association between dietary patterns and neuroimaging outcomes, which includes both specific pathological hallmarks of neurodegenerative diseases such as Aß and tau and nonspecific markers such as structural MRI and glucose metabolism. The risk of bias was evaluated using the Quality Assessment tool from the National Heart, Lung, and Blood Institute of the National Institutes of Health. The results were then organized into a summary of results table, collated based on synthesis without meta-analysis. After conducting the search, 6050 records were extracted and screened for eligibility, with 107 eligible for full-text screening and 42 articles ultimately being included in this review. The results of the systematic review indicate that there is some evidence suggesting that healthy dietary and nutrient patterns were associated with neuroimaging measures, indicative of a protective influence on neurodegeneration and brain ageing. Conversely, unhealthy dietary and nutrient patterns showed evidence pointing to decreased brain volumes, poorer cognition and increased Aß deposition. Future research should focus on sensitive neuroimaging acquisition and analysis methods, to study early neurodegenerative changes and identify critical periods for interventions and prevention. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no, CRD42020194444).
Subject(s)
Brain , Magnetic Resonance Imaging , United States , Humans , Aged , Middle Aged , Brain/diagnostic imaging , Brain/pathology , Neuroimaging/methods , Nutrients , Positron-Emission TomographyABSTRACT
Given the rise in worldwide chronic diseases, supplemented by an aging population, the volume of global major surgeries, encompassing cardiac and orthopedic procedures is anticipated to surge significantly. Surgical trauma can be accompanied by numerous postoperative complications and metabolic changes. The present review summarized the results from studies assessing the effects of orthopedic and cardiovascular surgery on vitamin concentrations, in addition to exploring the possible mechanisms associated with changes in concentrations. Studies have revealed a potentially severe depletion in plasma/serum concentrations of numerous vitamins following these surgeries acutely. Vitamins C, D and B1 appear particularly vulnerable to significant depletions, with vitamin C and D depletions consistently transpiring into inadequate and deficient concentrations, respectively. The possible multifactorial mechanisms impacting postoperative vitamin concentrations include changes in hemodilution and vitamin utilization, redistribution, circulatory transport and absorption. For a majority of vitamins, there has been a lack of investigation into the effects of both, cardiac and orthopedic surgery. Additionally, studies were predominantly restricted to short-term postoperative investigations, primarily performed within the first postoperative week of surgery. Overall, results indicated that further examination is necessary to determine the severity and clinical significance of the possible depletions in vitamin concentrations that ensue cardiovascular and orthopedic surgery.
Subject(s)
Orthopedic Procedures , Vitamins , Dietary Supplements , Vitamin A , Ascorbic AcidABSTRACT
Background: Previous randomized controlled trials examining cognitive and mood effects of combination multivitamin supplements in healthy, non-clinical adults have reported mixed results. One purported explanation for this is that the dietary status of participants at the start of supplement interventions may influence the magnitude of the effect of supplementation. Methods: In this study, we evaluated the effect of a multinutrient formula containing B group vitamins, Bacopa monniera and Ginkgo biloba on memory, attention, mood and biochemical markers of nutrient status in middle-aged adults (M = 52.84 years, n = 141) with 'optimal' and 'sub-optimal' diets over 12 weeks. We hypothesised that active supplementation would differentially improve memory and attention in those with a 'sub-optimal' diet. Results: Mixed model, repeated measures analysis revealed that, in comparison to placebo, active treatment was associated with significant increases in B vitamin status (B1, B6, B12). Regarding behavioural outcomes there was no significant benefit to memory (F(1, 113.51) = 0.53, p = 0.470) nor attention (F(1,113.77) = 1.89, p = 0.171) in the whole cohort. Contrary to our hypothesis, there was a significant beneficial effect of supplementation on attentional performance in individuals with an 'optimal' diet prior to supplementation (F(1,57.25) = 4.94, p = 0.030). In the absence of a main effect of supplementation across the entire cohort, there were also a number of significant three-way interactions (treatment by time by diet group) detected in secondary outcomes including lower state anxiety and mental fatigue in those with an 'optimal' diet. Conclusion: These findings suggest that the cognitive benefit of B vitamin and herbal supplementation may be dependent on diet quality, supporting the concepts of 'co-nutrient optimisation' and interdependency of nutrients. This warrants further investigation. This study advocates characterising the diet of participants prior to supplementation as it may influence the effect of a nutraceutical intervention.
Subject(s)
Bacopa , Vitamin B Complex , Humans , Middle Aged , Biomarkers , Cognition , Diet , Dietary Supplements , Double-Blind MethodABSTRACT
BACKGROUND: Homocysteine, a methionine metabolite, is a recognized risk factor for accelerated age-related cognitive decline and dementia. OBJECTIVE: In the light of studies indicating increases in brain activity and brain functional connectivity in the early stages of age-related cognitive decline, we undertook a study to examine the relationship between plasma homocysteine levels and brain functional connectivity in a group of late middle-aged males at risk of cognitive decline due to high body mass index and a sedentary lifestyle. METHODS: Brain functional connectivity was measured using the steady state visual evoked potential event related partial coherence while 38 participants performed a memory task where each trial comprised an object recognition task followed by a location memory task. RESULTS: We observed a significant transient peak in the correlation between plasma homocysteine levels and fronto-parietal brain functional connectivity immediately before the presentation of the memory location component of the task. Significantly, this correlation was only apparent if the participant pool included individuals with homocysteine concentrations above 11µmole/L. CONCLUSION: Our findings suggest that the increased brain functional connectivity observed in the earlier stages of age-related cognitive decline reflects pathognomonic changes in brain function and not compensatory changes engaged to enhance task performance. Our findings also suggest that homocysteine interferes with the inhibition of cortical networks where this inhibition is necessary for optimum task performance. Finally, we observed that the effect of homocysteine on brain functional connectivity is only apparent at concentrations above 11µmol/L.
Subject(s)
Evoked Potentials, Visual , Homocysteine , Male , Humans , Middle Aged , Magnetic Resonance Imaging , Brain , Memory/physiology , Brain Mapping , Neural Pathways/physiologyABSTRACT
Adherence to different dietary patterns has been linked to the development of cognitive decline; yet little is known about whether this relationship is present in middle age. The current study aimed to explore the relationship between different dietary patterns, cognitive performance, and potential cardio-metabolic mechanisms for this relationship. Participants were recruited using a diet screening tool to ensure that the cohort had a range of diet quality ranging from relatively poor to relatively healthy. In a sample of 141 middle-aged adults (age: M = 52.84 years, SD = 6.87 years), multiple 24 h diet recalls were collected and used to score adherence to the Mediterranean diet, dietary approaches to stop hypertension (DASH) diet, and Mediterranean-DASH diet intervention for neurodegenerative delay (MIND) diet. Metabolic risk was assessed using the metabolic syndrome severity score (MetSSS) and arterial stiffness. Cognitive performance was assessed using the Swinburne University Computerized Cognitive Assessment Battery (SUCCAB). Adherence to the MIND diet was significantly related to Stroop Processing domain (ß = 0.19, p = 0.035). None of the dietary patterns were significantly related to MetSSS or arterial stiffness. However, adherence to the DASH diet was significantly associated with two cardio-metabolic measures including lower augmentation index (ß = -0.17, p = 0.032) and lowered cholesterol (ß = -0.18, p = 0.041). Interestingly, two cardio-metabolic risk factors were also associated with better cognitive performance: MetSSS (ß = 0.21, p = 0.010) and waist circumference (ß = 0.22, p = 0.020). Together these findings suggest that diet in middle age may be important for cognitive functioning and cardio-metabolic risk. However, more research is needed in the form of randomized controlled trials to confirm the direction of these relationships.
ABSTRACT
BACKGROUND: Cognitive decline is influenced by various factors including diet, cardiovascular disease, and glucose control. However, the combined effect of these risk factors on cognitive performance is yet to be fully understood. OBJECTIVE: The current study aimed to explore the inter-relationship between these risk factors and cognitive performance in older adults at risk of future cognitive decline. METHODS: The sample comprised 163 (Age: Mâ=â65.23 years, SDâ=â6.50) participants. Food Frequency Questionnaire data was used to score diet quality and adherence to the Western Style Diet (WSD) and Prudent Style Diet (PSD). Glucose control was gauged by serum levels of glycated hemoglobin (HbA1c) and arterial stiffness was measured using carotid to femoral pulse wave velocity. Cognitive performance was assessed using two subtests of the Swinburne University Computerized Cognitive Assessment Battery (SUCCAB) and Rey's Verbal Learning Test (RVLT). RESULTS: Diet quality, adherence to the WSD or PSD, and glucose control were not significantly related to cognitive outcomes. However, a significant negative association was found between arterial stiffness and the spatial working memory subtest of SUCCAB (ß=â-0.21, pâ<â0.05). Arterial stiffness also significantly interacted with the PSD to impact total recall (F change (1,134)â=â5.37, pâ<â0.05) and the composite score of RVLT (F change (1,134)â=â4.03, pâ<â0.05). CONCLUSION: In this sample of older adults at risk of cognitive decline, diet alone was not found to predict cognitive performance; however, it was found to moderate the relationship between arterial stiffness and cognition.
Subject(s)
Cognitive Aging/physiology , Cognitive Dysfunction/physiopathology , Diet , Vascular Stiffness/physiology , Aged , Cognitive Dysfunction/etiology , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Pulse Wave Analysis , Risk FactorsABSTRACT
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.
Subject(s)
Cognitive Dysfunction , Diet, Mediterranean , Aged , Cognitive Dysfunction/epidemiology , Cross-Sectional Studies , Health Status , Humans , Middle Aged , Prospective StudiesABSTRACT
BACKGROUND: Post-operative cognitive function has recently become an area of focus for researchers. The most commonly reported perioperative neurocognitive disorders include delirium and longer-lasting post-operative cognitive dysfunctions. The contributing pathophysiology to these complications remains unclear. A number of studies have systematically revealed a significant post-operative plasma vitamin C depletion. Recent insights have also exhibited a link between plasma vitamin C and numerous biological roles in brain function, with deficiencies potentially compromising cognitive function. AIM: The present prospective, observational study will investigate whether there is a possible link between post-operative plasma vitamin C depletion and cognitive dysfunction. METHODS: The cohort will consist of surgical patients, between the ages of 65 and 85 years, undergoing hip replacement surgery or a control group not exposed to surgical trauma. Participants will have their plasma vitamin C concentrations tested alongside a battery of computer-based cognitive assessments and paper and pen based cognitive tests. Further assessments will include dietary nutritional intake, serum vitamin B12 concentrations, cardiovascular biomarkers, wound healing, sleep quality, pain, mood and inflammatory cytokines. Participants will be tested at baseline (1-2 weeks prior to surgery) and subsequent testing sessions will be performed within 1 week, 4-6 weeks, 3 months and 6 months following surgery. CONCLUSIONS: Findings from this observational study will provide insight into whether there is a concomitant depletion in post-operative plasma vitamin C concentrations and cognition function. Extrapolated results may prompt future, extensive randomized controlled trials to assess whether vitamin C supplementation can alleviate or even prevent post-operative cognitive complications.
Subject(s)
Ascorbic Acid , Cognition , Aged , Aged, 80 and over , Humans , Observational Studies as Topic , Prospective Studies , VitaminsABSTRACT
Many researchers have identified the issue of self-selection bias hindering the ability to detect nutrient effects in healthy populations. However, it appears that no effort has been made to mitigate this potential design flaw. By recruiting individuals on the basis of pre-trial dietary intake, the Memory and Attention Supplementation Trial aimed to capture a cohort of participants with a wide variety of dietary intake, thus increasing the likelihood of a diverse range of nutrient status. This perspective specifically examines the profile of these trial volunteers and in doing so, we present the first empirical evidence of self-selection bias when recruiting healthy volunteers for a randomized controlled trial of a nutrient-based supplement. These findings support the anecdotal proposal that traditional recruitment methods inherently attract trial volunteers who are vastly unrepresentative of the population and threatens the generalizability of this field of research. Alternative approaches to recruitment, including a-priori screening for baseline diet quality and nutrient status, are discussed as essential design recommendations to ensure accurate interpretation of nutrient effects within the context of baseline participant characteristics.
ABSTRACT
Evidence for diet quality representing a modifiable risk factor for age-related cognitive decline and mood disturbances has typically come from retrospective, cross-sectional analyses. Here a diet screening tool (DST) was used to categorize healthy middle-aged volunteers (n = 141, 40-65 years) into "optimal" or "sub-optimal" diet groups to investigate cross-sectional associations between diet quality, cognitive function, and mood. The DST distinguished levels of nutrient intake as assessed by Automated Self-Administered 24-h dietary recall and nutrient status, as assessed by blood biomarker measures. Compared with the "sub-optimal" group, the "optimal" diet group showed significantly higher intake of vitamin E (p = 0.007), magnesium (p = 0.001), zinc (p = 0.043) and fiber (p = 0.015), higher circulating levels of vitamin B6 (p = 0.030) and red blood cell folate (p = 0.026) and lower saturated fatty acids (p = 0.012). Regarding psychological outcomes, the "optimal" diet group had significantly better Stroop processing than those with a "sub-optimal" diet (p = 0.013). Regression analysis revealed that higher DST scores were associated with fewer mood disturbances (p = 0.002) and lower perceived stress (p = 0.031), although these differences were not significant when comparing "optimal" versus "sub-optimal" as discrete groups. This study demonstrates the potential of a 20-item diet screen to identify both nutritional and psychological status in an Australian setting.
Subject(s)
Affect , Cognition , Diet Surveys/methods , Diet, Healthy/statistics & numerical data , Nutritional Status , Adult , Aged , Australia , Biomarkers/blood , Cross-Sectional Studies , Diagnostic Self Evaluation , Diet, Healthy/psychology , Eating/psychology , Energy Intake , Female , Healthy Volunteers , Humans , Male , Middle Aged , Nutrients/blood , Nutritive Value , Regression Analysis , Self Report , Stress, Psychological/etiology , Stroop TestABSTRACT
There is increasing evidence that sex differences in the brain may contribute to gender-related behavioral differences, including cognitive function. Literature has revealed gender dimorphisms in cognitive function between males and females. Additionally, several risk factors associated with cognitive decline depend on chronological age. It is well recognized that the process of aging is associated with a decline in cognitive ability and brain function. Various explanations may account for these gender-related cognitive differences and age-associated cognitive changes. Recent investigations have highlighted the importance of vitamin C in maintaining brain health and its association with cognitive function in both cognitively intact and impaired cohorts. The present review explores previous literature that has evaluated differences in plasma/brain vitamin C between genders and during aging. It then assesses whether these age and gender-related differences may affect the relationship between plasma/brain vitamin C and cognition. The purpose of this review was to examine the evidence for a link between plasma/brain vitamin C and cognition and the impact of gender and age on this relationship. Epidemiological studies have frequently shown higher vitamin C plasma concentrations in women. Similarly, aging has been systematically associated with reductions in plasma vitamin C levels. A range of animal studies has demonstrated potential gender and age-related differences in vitamin C brain distribution and utilization. The reviewed literature suggests that gender differences in plasma and brain vitamin C may potentially contribute to differences in gender-associated cognitive ability, particularly while females are pre-menopausal. Additionally, we can propose that age-associated differences in plasma and brain vitamin C may be potentially linked to age-associated cognitive differences, with older cohorts appearing more vulnerable to experience declines in plasma vitamin C concentrations alongside compromised vitamin C brain regulation. This review encourages future investigations to take into account both gender and age when assessing the link between plasma vitamin C concentrations and cognitive function. Further large scale investigations are required to assess whether differences in cognitive function between genders and age groups may be causally attributed to plasma vitamin C status and brain distribution and utilization.
ABSTRACT
Extra virgin olive oil (EVOO) is suggested to be cardioprotective, partly due to its high phenolic content. We investigated the effect of extra virgin high polyphenol olive oil (HPOO) versus low polyphenol olive oil (LPOO) on blood pressure (BP) and arterial stiffness in healthy Australian adults. In a double-blind, randomized, controlled cross-over trial, 50 participants (age 38.5 ± 13.9 years, 66% female) were randomized to consume 60 mL/day of either HPOO (360 mg/kg polyphenols) or LPOO (86 mg/kg polyphenols) for three weeks. Following a two-week washout period, participants crossed over to consume the alternate oil. Anthropometric data, peripheral BP, central BP and arterial stiffness were measured at baseline and follow up. No significant differences were observed in the changes from baseline to follow up between the two treatments. However, a significant decrease in peripheral and central systolic BP (SBP) by 2.5 mmHg (95% CI: -4.7 to -0.3) and 2.7 mmHg (95% CI: -4.7 to -0.6), respectively, was observed after HPOO consumption. Neither olive oil changed diastolic BP (DBP) or measures of arterial stiffness. The reductions in SBP after HPOO consumption provide evidence for a potentially widely accessible dietary intervention to prevent cardiovascular disease in a multiethnic population. Longer intervention studies and/or higher doses of EVOO polyphenols are warranted to elucidate the potential effect on DBP and arterial stiffness.
Subject(s)
Blood Pressure/drug effects , Dietary Supplements , Olive Oil/chemistry , Polyphenols/pharmacology , Vascular Stiffness/drug effects , Adult , Australia , Cardiovascular Diseases/prevention & control , Cross-Over Studies , Double-Blind Method , Female , Healthy Volunteers , Heart Disease Risk Factors , Humans , Male , Middle AgedABSTRACT
Post-operative neurocognitive disorders are becoming well-documented conditions, with their pathogenesis remaining unclear. Vitamin C is a molecule that has recently demonstrated both a potential link with cognitive function and a significant post-operative decline. Here, we present a case study of a 72-year-old male who underwent total knee replacement surgery. The patient demonstrated a substantial decline in plasma vitamin C concentrations, indicative of a severe deficiency, during the first post-operative week (post-operative Days 3 and 7). Similarly, at these time points, a number of validated paper and pen tests revealed a substantial decline in cognition on tasks relating to total recall, delayed recall, motor speed, recognition and motor speed, with no signs of delirium. These results provide the justification for larger, cohort studies to determine whether post-operative plasma vitamin C depletions could contribute to cognitive deficits post-operatively.