Dietary Mineral Intake and Risk of Mild Cognitive Impairment: The PATH through Life Project

Lifestyle, Environment, and Dietary Measures Impacting Cognitive Impairment: The Evidence Base for Cognitive Subtypes

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Cognition includes all phases of valid functions and processes, e.g., sensitivity, judgment, assessment, and decision-making. Thinking is also a cognitive procedure since it involves considering potential opportunities. There are various types of cognition. Hot cognition involves mental procedures where emotion plays a role, while cold cognition includes mental processes that do not include feelings or emotions. Cognitive memories of various types include sensor memory, sensing touch, smell, and sight; short-term memory allows one to recall, e.g., what one had for lunch a few days ago; working memory includes remembering telephone numbers or directions to a destination; and long-term memory comprises of major milestones in life and recalling one’s childhood events. These are further classified as episodic, e.g., the first day in primary school, and semantic memories, such as recalling the capital city of a country and filling out crossword puzzles. Declarative memories include remembering significant past events, such as global information. Cognition is affected by factors, such as nutrition, aging, addiction, environment, mental health, physical activity, smoking, and keeping the brain active. Consumption of plant- based foods plays a prominent role in the prevention of cognitive memory. Playing games and instruments, reading books, and being socially active make life more satisfying, thus assisting in the preservation of mental function and slowing mental decline.

Cross-sectional and longitudinal associations of magnesium intake and cognition in the Healthy Aging Longitudinal Study in Taiwan

PURPOSE

Previous cross-sectional studies have shown that higher magnesium intake is associated with better cognitive function, particularly in individuals with sufficient vitamin D status. The aim of this study was to evaluate the longitudinal associations between magnesium intake and cognitive impairment in a community-based cohort study in Taiwan.

METHODS

The study population included 5663 community-dwelling adults aged ≥ 55 years old recruited from 2009 to 2013 and followed up from 2013 to 2020. Magnesium intake was evaluated from a validated food frequency questionnaire at baseline. Cognitive performance was measured at baseline and follow-up for participants' Mini-Mental Status Examination (MMSE), Digit Symbol Substitution Test (DSST), and Clock-Drawing Test (CDT), and impairment was defined as MMSE < 24, DSST < 21, and CDT < 3, respectively. Multivariate logistic regression models were used to examine the associations and were stratified by sex and plasma vitamin D levels (≥ 50 or < 50 nmol/L).

RESULTS

Higher baseline magnesium intake was associated with lower odds of a poor performance on the MMSE in both men and women (4th vs. 1st. quartile: OR = 0.43, 95% CI = 0.23-0.82, ptrend < 0.01 in men and OR = 0.53, 95% CI = 0.29-0.97, ptrend = 0.12 in women) and on the DSST in men (OR = 0.23, 95% CI = 0.09-0.61, ptrend < 0.01) at follow-up. Inverse associations between baseline magnesium intake and a poor performance on the MMSE or DSST were observed in men regardless of vitamin D status.

CONCLUSION

Our study suggested that higher magnesium intake was associated with the development of cognitive impairment in men in a median follow-up period of 6 years.

Magnesium (Mg) and Neurodegeneration: A Comprehensive Overview of Studies on Mg Levels in Biological Specimens in Humans Affected Some Neurodegenerative Disorders with an Update on Therapy and Clinical Trials Supplemented with Selected Animal Studies

Neurodegenerative diseases, characterized by neuron loss, are a group of neurological disorders that adversely affect the lives of millions of people worldwide. Although several medicines have been approved for managing neurodegenerative diseases, new therapies allowing for a significant slowdown in the progression of neurodegenerative syndromes are constantly being sought. Magnesium (Mg), a crucial mineral necessary for the functioning of organisms, is important to normal central nervous system (CNS) activity. Although the effects of this bioelement on the CNS are relatively well recognized, its role in the pathophysiology of neurological disorders in humans is not yet well characterized. Therefore, the main goal of this review is to collect data about a possible association between Mg and neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's Disease (PD), and Amyotrophic lateral sclerosis (ALS) in humans. Hence, the levels of Mg in blood, cerebrospinal fluid (CSF), urine, and hair from subjects with AD, PD, and ALS are compiled to detect possible variations in the levels of this mineral in the biological specimens of people with neurodegenerative illnesses. Additionally, the findings from an animal model are summarized to offer the reader a deeper insight into studies on Mg in the context of neuroprotection and neurodegeneration. Data provided in the present review indicate that Mg, due to its neuroprotective, antioxidant, anti-inflammatory, and mitochondrial-supportive properties, could be a potential therapeutic agent for AD, PD, and ALS. However, more epidemiological studies with standardized methods of dietary assessment and Mg measurement are necessary to recognize its exact role in neurodegenerative disorders. Moreover, extensive well-designed clinical trials are also needed to establish definitive therapeutic protocols and optimal dosages, and to ensure long-term safety of this mineral supplementation in AD, PD, and ALS patients.

High Blood Pressure and Impaired Brain Health: Investigating the Neuroprotective Potential of Magnesium

High blood pressure (BP) is a significant contributor to the disease burden globally and is emerging as an important cause of morbidity and mortality in the young as well as the old. The well-established impact of high BP on neurodegeneration, cognitive impairment, and dementia is widely acknowledged. However, the influence of BP across its full range remains unclear. This review aims to explore in more detail the effects of BP levels on neurodegeneration, cognitive function, and dementia. Moreover, given the pressing need to identify strategies to reduce BP levels, particular attention is placed on reviewing the role of magnesium (Mg) in ageing and its capacity to lower BP levels, and therefore potentially promote brain health. Overall, the review aims to provide a comprehensive synthesis of the evidence linking BP, Mg and brain health. It is hoped that these insights will inform the development of cost-effective and scalable interventions to protect brain health in the ageing population.

Micronutrient Deficiencies in Older Adults in Latin America: A Narrative Review

BACKGROUND

The population in Latin America and Caribbean (LAC) has experienced a major demographic transition with increased numbers of older adults (OA). This change brings opportunities in the public health sector to implement health prevention interventions and delay the onset of geriatric syndromes. Micronutrients play an important role in the maintenance of biological function which contributes to longevity. Micronutrient deficiencies (MD) in OA increase the risk for onset of chronic comorbidities and geriatric syndromes.

AIM

To review and summarize the existing data on micronutrient status in OA in the LAC region and discuss the gaps and challenges in public health approaches to address deficiencies.

METHODS

Literature review in Medline for records describing nutritional biomarkers in older adults (≥ 60y) from community dwelling and population-based studies in LAC.

RESULTS

Few countries (including Chile, Ecuador, Costa Rica, Brazil, and Mexico) have documented one or more nutritional deficiencies for OA in national health surveys, however across the entire region, evidence of micronutrient levels is scarce. Some surveys have documented a high prevalence and large heterogeneity in the prevalence of vitamin D followed by B12 deficiency, being the 2 MDs most studied due their effects on cognition, frailty, and bone mineral density in the OA population. Other MD including C, E, A, copper, zinc, iron, and selenium have also been reported.

CONCLUSION

Information on the micronutrient status in OA from LAC is poorly documented. Research and capacity building initiatives in the region are crucial to develop tailored strategies that address the specific nutritional needs and challenges faced by the ageing population in Latin America.

Prevalence and Factors Associated With Healthy Aging in a Large Representative Community Sample of Older Ethiopians

Objectives: To examine the prevalence and predictors of healthy aging among community-dwelling older adults living in Bahir Dar, Ethiopia. Methods: A community-based cross-sectional study included older adults aged 60 and above (n = 845; Mage = 71 years; 56.4% females). Poisson regression estimated the Relative Risk (RR) of factors associated with healthy aging status. Results: 36.7% of respondents were classified as healthy agers. Factors associated with an increased likelihood of healthy aging included reporting not being lonely, adequate nutrition, no multimorbidity, good self-rated health, financial independence, and engaging in at least 1 hour of moderate physical activity per week. Discussion: The proportion of healthy agers in this study was substantially lower compared to developed countries but comparable to the prevalence reported in similar developing nations. Enhancing physical activity, ensuring proper nutrition, interventions to foster social participation engagement, and networking, and managing chronic diseases were identified as promising strategies to promote healthy aging.

Brain of miyoshi myopathy/dysferlinopathy patients presents with structural and metabolic anomalies

Miyoshi myopathy/dysferlinopathy (MMD) is a rare muscle disease caused by DYSF gene mutations. Apart from skeletal muscles, DYSF is also expressed in the brain. However, the impact of MMD-causing DYSF variants on brain structure and function remains unexplored. To investigate this, we utilized magnetic resonance (MR) modalities (MR volumetry and 31P MR spectroscopy) in a family with seven children, four of whom have the illness. The MMD siblings showed distinct differences from healthy controls: (1) a significant (p < 0.001) right-sided volume asymmetry (+ 232 mm3) of the inferior lateral ventricles; and (2) a significant (p < 0.001) decrease in [Mg2+], along with a modified energy metabolism profile and altered membrane turnover in the hippocampus and motor and premotor cortices. The patients' [Mg2+], energy metabolism, and membrane turnover measures returned to those of healthy relatives after a month of 400 mg/day magnesium supplementation. This work is the first to describe anatomical and functional abnormalities characteristic of neurodegeneration in the MMD brain. Therefore, we call for further examination of brain functions in larger cohorts of MMD patients and testing of magnesium supplementation, which has proven to be an effective corrective approach in our study.

Modifiable risk factors for mild cognitive impairment among cognitively normal community-dwelling older adults: A systematic review and meta-analysis

Although numerous studies have investigated modifiable risk factors for mild cognitive impairment (MCI) among community-dwelling seniors, no meta-analysis has summarized these findings. Five databases were searched from January 1, 2000, to December 30, 2023. The protocol was registered with PROSPERO. Data were extracted and reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant meta-analyses of modifiable risk factors were performed. The evidence of each factor was assessed by the GRADE for cohort studies. Of 16,651 citations, 87 studies involving 225,584 community-dwelling seniors were included. Fourteen meta-analyses involving 20 studies with 44,199 participants were performed. The analyses revealed low-to-moderate-quality evidence supporting that diabetes, 2 or more comorbidities, anxiety, apathy, depressive symptoms, and physical frailty were risk factors for incident MCI in older adults. Conversely, hypertension, agitation, and irritability might not be risk factors. Additionally, moderate-quality evidence supports the protective effect of engaging in cognitive-demanding activities on the onset of MCI. Collectively, this study constitutes the first extensive compilation of evidence regarding the various risk factors for the development of MCI in older adults. Our findings hold significant potential to guide the formulation of prevention and management strategies to either prevent or potentially reverse the onset of MCI.

Association between dietary magnesium intake, inflammation, and neurodegeneration

BACKGROUND

Consistent evidence shows that magnesium (Mg) intake is associated with lower blood pressure (BP), and that lower BP is associated with improved cerebral health. However, recent findings indicate that the positive effect of dietary Mg intake on cerebral health is not mediated by a decrease in BP. As Mg's anti-inflammatory action is a plausible alternative mechanism, the objective of this study was to investigate the associations between Mg intake and inflammation to determine whether it mediates any neuroprotective effect.

METHODS

Participants from the UK Biobank (n = 5775, aged 40-73 years, 54.7% female) were assessed for dietary magnesium using an online food questionnaire, brain and white matter lesion (WML) volumes were segmented with FreeSurfer software, and inflammation markers including high-sensitivity C-reactive protein (hs-CRP), leukocyte, erythrocyte count, and Glycoprotein acetylation (GlycA) were measured using specific laboratory techniques such as immunoturbidimetry, automated cell counting, and nuclear magnetic resonance. Hierarchical linear regression models were performed to investigate the association between dietary Mg, and inflammatory markers and between dietary Mg, brain and WMLs volumes. Mediation analysis was performed to test a possible mediation role of inflammation on the association between dietary Mg and brain and WMLs volumes.

RESULTS

Higher dietary Mg intake was associated with lower inflammation: hs-CRP level (- 0.0497%; 95% confidence interval [CI] - 0.0497%,  - 0.0199%) leukocytes count (- 0.0015%; 95%CI - 0.00151%,  - 0.0011%), and GlycA (- 0.0519%; 95%CI - 0.1298%,  - 0.0129%). Moreover, higher dietary Mg intake was associated with larger grey matter volume (0.010%; 95%CI 0.004%, 0.017%), white matter volume (0.012%; 95%CI 0.003,  0.022) and right hippocampal volume (0.002%; 95%CI 0.0007, -0.0025%). Lower hs-CRP levels mediated the positive association between higher dietary Mg intake and larger grey matter volume.

CONCLUSIONS

The anti-inflammatory effects of dietary Mg intake in the general population, appears to mediate its neuroprotective effect.

Comparison of Eating Habits, Body Composition and Densitometric Parameters between Subjects with Normal Cognitive Function and Mild Cognitive Impairment: An Observational Study

The role of nutrition in the ageing process of the brain is pivotal. Therefore, the study aimed to compare eating habits, body composition and densitometric parameters between subjects with normal cognitive function (NCF) and mild cognitive impairment (MCI). A total of 95 subjects with NCF (74% of women) and 95 individuals with MCI (77% of women) aged 50-70 years were studied. Densitometric parameters were evaluated using dual-energy X-ray absorptiometry methods. Eating habits were assessed using the food frequency questionnaire and 3-day diary records, and advanced glycation end products (AGEs) intake was calculated. Significant differences between groups were detected for the %fat in the right arm (NCF vs. MCI: 38.4 (30.4-46.8) vs. 43.5 (35.5-49.2)%, p = 0.0407). Moreover, the MCI group had a significantly lower intake of calcium (p = 0.0010), phosphor (p = 0.0411), vitamins B2 (p = 0.0138) and B12 (p = 0.0024) compared to the NCF group, with both groups also differing in the frequency of butter (p = 0.0191) and fermented milk beverages (p = 0.0398) intake. Analysis restricted to women showed significant differences between groups in right arm %fat, VAT mass, calcium, vitamins B2, B12, butter and fermented milk products intake, while in men, differences were detected in the intake of calcium, iodine, vitamin B1, water and AGEs. In conclusion, subjects with NCF and MCI have comparable densitometric variables but differ significantly in some body composition parameters and the intake of some food groups and nutrients.

Adequate dietary magnesium intake may protect females but not males older than 55 years from cognitive impairment

BACKGROUND

Magnesium is an essential nutrient required to maintain brain health throughout life, and adequate magnesium intake is positively associated with cognitive performance in older adults. However, sex differences in magnesium metabolism have not been adequately assessed in humans.

OBJECTIVES

We investigated sex differences in the effect of dietary magnesium intake and the risk of different types of cognitive impairment in older Chinese adults.

METHODS

We collected and assessed dietary data and cognitive function status in people aged 55 years and older in northern China who participated in the Community Cohort Study of Nervous System Diseases from 2018 to 2019 to explore the relationship between dietary magnesium intake and the risk of each type of mild cognitive impairment (MCI) in sex-specific cohorts of older adults.

RESULTS

The study included 612 people: 260 (42.5%) men and 352 (57.5%) women. Logistic regression results showed that for the total sample and women's sample, high dietary magnesium intake reduced the risk of amnestic MCI (ORtotal = 0.300; ORwomen = 0.190) and multidomain amnestic MCI (ORtotal = 0.225; ORwomen = 0.145). The results of restricted cubic spline analysis showed that the risk of amnestic MCI (ptotal = 0.0193; pwomen = 0.0351) and multidomain amnestic MCI (ptotal = 0.0089; pwomen = 0.0096) in the total sample and women's sample gradually decreased with increasing dietary magnesium intake.

CONCLUSIONS

The results suggest that adequate magnesium intake may have a preventive effect against the risk of MCI in older women.

Mineral Supplements in Ageing

With advancing age, achievement of dietary adequacy for all nutrients is increasingly difficult and this is particularly so for minerals. Various factors impede mineral acquisition and absorption including reduced appetite, depressed gastric acid production and dysregulation across a range of signalling pathways in the intestinal mucosa. Minerals are required in sufficient levels since they are critical for the proper functioning of metabolic processes in cells and tissues, including energy metabolism, DNA and protein synthesis, immune function, mobility, and skeletal integrity. When uptake is diminished or loss exceeds absorption, alternative approaches are required to enable individuals to maintain adequate mineral levels. Currently, supplementation has been used effectively in populations for the restoration of levels of some minerals like iron, zinc, and calcium, but these may not be without inherent challenges. Therefore, in this chapter we review the current understanding around the effectiveness of mineral supplementation for the minerals most clinically relevant for the elderly.

Association between Mineral Intake and Cognition Evaluated by Montreal Cognitive Assessment (MoCA): A Cross-Sectional Study

BACKGROUND

Mineral intake may protect against cognitive impairment (CI) and all-cause dementia, which affects a large number of adults worldwide. The aim of this study was to investigate the association between mineral intake and Montreal Cognitive Assessment (MoCA), which is a sensitive and specific test.

METHODS

In total, 201 adults were included in a cross-sectional study. They completed a three-day dietary record to estimate their average daily intake of minerals. Contributions to dietary reference intakes (DRIs) were also calculated. The participants were divided into tertiles according to their mineral intake. CI classifications were determined via the MoCA (score < 26). Apolipoprotein E (APOE) genotyping was carried out, and the patients' anthropometric measurements and physical activity, health and personal data were collected.

RESULTS

The prevalence of CI in this selective sample was 54.2% (34.3% females and 19.9% males). In women, being in the third tertiles of iron and manganese intake was associated with lower odds of having CI (OR [95% CI]: 0.32 [0.11 ± 0.93]; 0.33 [0.12 ± 0.93], p < 0.05). No significant differences were observed for any of the nutrients studied in men.

CONCLUSIONS

These findings suggest that a low mineral intake, especially low iron and manganese intake in women, is associated with a worse cognition as assessed by MoCA.

Relationship between Whole-Blood Magnesium and Cognitive Performance among Chinese Adults

OBJECTIVE

To explore the association between magnesium levels and the odds of mild cognitive impairment (MCI).

METHOD

In this cross-sectional study of 1006 participants (≥55 years) from China, whole-blood magnesium concentration was measured using inductively coupled plasma mass spectrometry. MCI was diagnosed according to Petersen criteria using self-reported cognitive decline and a neuropsychological test battery, including the trail-making test-part B (TMT-B), auditory verbal learning test (AVLT), digit symbol substitution test (DSST), and verbal fluency test (VFT), which measured the assessment of executive, memory, attention, and language functioning, respectively. A logistic regression was used to assess the relationship between magnesium levels and MCI, and linear regression analyses were performed for the association between magnesium and cognitive function score.

RESULTS

The MCI group had a significantly lower concentration of magnesium compared to the Non-MCI group (34.7 ± 9.8 vs. 36.7 ± 9.7, p = 0.017). After adjusting for covariates, a negative association was observed between magnesium levels and MCI. Compared with the lowest quartile (median: 25.4 mg/L), the odds ratio for MCI was 0.53 (95%CI 0.32-0.90) for the highest quartile (median: 48.4 mg/L), and there was an inverse dose-response relationship (p for trend = 0.009). In addition, higher levels of magnesium were positively correlated with VFT scores (β = 0.37, 95%CI = 0.11-0.62) and DSST scores (β = 0.50, 95%CI = 0.01~0.98) and negatively correlated with TMT scores (β = -1.73, 95%CI = -3.40--0.07) in the middle-aged and older adults.

CONCLUSIONS

Whole-blood magnesium was inversely associated with the occurrence of MCI and positively associated with performance in neuropsychological tests assessing attention, executive, and language ability in middle-aged and older adults.

Metals in Alzheimer's Disease

The role of metals in the pathogenesis of Alzheimer's disease (AD) is still debated. Although previous research has linked changes in essential metal homeostasis and exposure to environmental heavy metals to the pathogenesis of AD, more research is needed to determine the relationship between metals and AD. In this review, we included human studies that (1) compared the metal concentrations between AD patients and healthy controls, (2) correlated concentrations of AD cerebrospinal fluid (CSF) biomarkers with metal concentrations, and (3) used Mendelian randomization (MR) to assess the potential metal contributions to AD risk. Although many studies have examined various metals in dementia patients, understanding the dynamics of metals in these patients remains difficult due to considerable inconsistencies among the results of individual studies. The most consistent findings were for Zn and Cu, with most studies observing a decrease in Zn levels and an increase in Cu levels in AD patients. However, several studies found no such relation. Because few studies have compared metal levels with biomarker levels in the CSF of AD patients, more research of this type is required. Given that MR is revolutionizing epidemiologic research, additional MR studies that include participants from diverse ethnic backgrounds to assess the causal relationship between metals and AD risk are critical.

Dietary magnesium intake is related to larger brain volumes and lower white matter lesions with notable sex differences

PURPOSE

To examine the association between dietary magnesium (Mg) intake and brain volumes and white matter lesions (WMLs) in middle to early old age.

METHODS

Participants (aged 40-73 years) from UK Biobank (n = 6001) were included and stratified by sex. Dietary Mg was measured using an online computerised 24 h recall questionnaire to estimate daily Mg intake. Latent class analysis and hierarchical linear regression models were performed to investigate the association between baseline dietary Mg, Mg trajectories, and brain volumes and WMLs. Associations between baseline Mg, and baseline blood pressure (BP) measures, and baseline Mg, Mg trajectories and BP changes (between baseline and wave 2) were also investigated to assess whether BP mediates the link between Mg intake and brain health. All analyses controlled for health and socio-demographic covariates. Possible interactions between menopausal status and Mg trajectories in predicting brain volumes and WMLs were also investigated.

RESULTS

On average, higher baseline dietary Mg intake was associated with larger brain volumes (gray matter [GM]: 0.001% [SE = 0.0003]; left hippocampus [LHC]: 0.0013% [SE = 0.0006]; and right hippocampus [RHC]: 0.0023% [SE = 0.0006]) in both men and women. Latent class analysis of Mg intake revealed three classes: "high-decreasing" (men = 3.2%, women = 1.9%), "low-increasing" (men = 1.09%, women = 1.62%), and "stable normal" (men = 95.71%, women = 96.51%). In women, only the "high-decreasing" trajectory was significantly associated with larger brain volumes (GM: 1.17%, [SE = 0.58]; and RHC: 2.79% [SE = 1.11]) compared to the "normal-stable", the "low-increasing" trajectory was associated with smaller brain volumes (GM: - 1.67%, [SE = 0.30]; white matter [WM]: - 0.85% [SE = 0.42]; LHC: - 2.43% [SE = 0.59]; and RHC: - 1.50% [SE = 0.57]) and larger WMLs (1.6% [SE = 0.53]). Associations between Mg and BP measures were mostly non-significant. Furthermore, the observed neuroprotective effect of higher dietary Mg intake in the "high-decreasing" trajectory appears to be greater in post-menopausal than pre-menopausal women.

CONCLUSIONS

Higher dietary Mg intake is related to better brain health in the general population, and particularly in women.

Revisiting the Role of Vitamins and Minerals in Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia that affects millions of individuals worldwide. It is an irreversible neurodegenerative disorder that is characterized by memory loss, impaired learning and thinking, and difficulty in performing regular daily activities. Despite nearly two decades of collective efforts to develop novel medications that can prevent or halt the disease progression, we remain faced with only a few options with limited effectiveness. There has been a recent growth of interest in the role of nutrition in brain health as we begin to gain a better understanding of what and how nutrients affect hormonal and neural actions that not only can lead to typical cardiovascular or metabolic diseases but also an array of neurological and psychiatric disorders. Vitamins and minerals, also known as micronutrients, are elements that are indispensable for functions including nutrient metabolism, immune surveillance, cell development, neurotransmission, and antioxidant and anti-inflammatory properties. In this review, we provide an overview on some of the most common vitamins and minerals and discuss what current studies have revealed on the link between these essential micronutrients and cognitive performance or AD.

Dietary Intake Levels of Iron, Copper, Zinc, and Manganese in Relation to Cognitive Function: A Cross-Sectional Study

Background: Previous studies have related circulating levels of trace metal elements, of which dietary intake is the major source, to cognitive outcomes. However, there are still relatively few studies evaluating the associations of dietary intake levels of iron, copper, zinc, and manganese with cognitive function (CF). Methods: We leveraged the data of 6863 participants (mean [standard deviation] age = 66.7 [10.5] years) in the Health and Retirement Study (2013/2014). Dietary intake levels of iron, copper, zinc, and manganese were calculated from a semi-quantitative food frequency questionnaire. CF was assessed using the 27-point modified Telephone Interview for Cognitive Status (TICS). We used linear regression models to calculate the mean differences in global CF scores by quintiles of dietary intake levels of trace metal elements. Results: Among the study participants, the mean (SD) values of daily dietary intake were 13.3 (6.3) mg for iron, 1.4 (0.7) mg for copper, 10.7 (4.6) mg for zinc, and 3.3 (1.6) mg for manganese. Compared with the lowest quintile of dietary iron intake (<8.1 mg), the highest quintile (≥17.7 mg) was associated with a lower cognitive score (-0.50, -0.94 to -0.06, P-trend = 0.007). Higher dietary copper was significantly associated with poorer CF (P-trend = 0.002), and the mean difference in cognitive score between extreme quintiles (≥1.8 vs. <0.8 mg) was -0.52 (95% confidence interval: -0.94 to -0.10) points. We did not observe significant associations for dietary intake of zinc (P-trend = 0.785) and manganese (P-trend = 0.368). Conclusion: In this cross-sectional study, higher dietary intake of iron and copper was related to worse CF, but zinc and manganese intake levels were not significantly associated with CF.

The Association between Dietary Iron Intake and Incidence of Dementia in Adults Aged 60 Years or over in the UK Biobank

Background Several studies have investigated the association between dietary iron intake and cognitive impairment, but little is known about the relationship between iron intake and dementia incidence. Objectives This study explored the association between dietary iron intake and incident dementia in males and females. Whether this association was modified by factors such as age and medical diseases was also examined. Methods We included 41,213 males and 48,892 females aged 60 years or over, from the UK-Biobank cohort. Dietary iron intake was measured using a web-based 24-h dietary recall questionnaire from between 2009 and 2012. Incident dementia was ascertained using hospital inpatient records and death registers until April 2021. Cox proportional regression models examined the association between iron intake and incident dementia, and hazard ratio curves were constructed with knots from the analysis indicating insufficient or excessive iron intake. Results During a mean follow-up of 11.8 years, 560 males and 492 females developed dementia. A non-linear relationship between iron intake and incident dementia was observed in both males and females. The lowest incidence rates were observed in the higher iron intake quintile (Q4: ≥15.73, <17.57 mg/day) for males, and the intermediate iron intake quintile (Q3: ≥12.4, <13.71 mg/day) for females. Among those aged 60 and above, all-cause dementia in males was associated with deficient iron intake (Q1 versus Q4: Hazard ratio [HR]: 1.37, 95% Confidence interval [95%CI]: 1.01−1.86, p = 0.042) and excessive iron intake (Q5 versus Q4: HR: 1.49, 95%CI: 1.14−1.96, p = 0.003), whilst significant associations between all-cause dementia and deficient iron intake were only observed in females without hypertension. Smoking status was a significant moderator (p-value for trend = 0.017) for dementia in males only. Conclusions Excessive iron intake (≥17.57 mg/day) is associated with a higher incidence of all-cause dementia in males and smoking status modified this association amongst males. Deficient iron intake (<10.93 mg/day) was associated with a higher incidence of all-cause dementia in females without a history of hypertension.

Micro- and Macronutrient Intake and Food Group Frequency Consumed by Subjects with Cognitive Impairment and Dementia in Latin America: A Systematic Review

BACKGROUND

Nutrition has relevant role in the pathogenesis of dementia. However, in Latin American Countries (LAC), it is unknown which type of diet the subjects with dementia and cognitive dysfunction have.

OBJECTIVE

The main purpose of this study was to determine micro- and macronutrients and food frequency intake among the LAC population with mild cognitive impairment (MCI) and dementia.

METHODS

A systematic review using PubMed, Cochrane, Lilacs, and Scielo databases. Energy intake as well as micro- and macronutrients intake were analyzed using a random-effect model and presented in a forest plot.

RESULTS

Nine articles were included, an estimated energy intake of 1598.47 kcal (95% CI 1351.07-1845.88) was obtained. A daily consumption of 73.64 g/day (95% CI 64.07-83.2) of protein; 262.17 g/day (95% CI 214.51-309.93) of carbohydrates, and 57.91 g/day (95% CI 49.16-66.66) of fats were reported. A micronutrients daily intake consumption of 201.35μg/day of vitamin B9 (95% CI 125.32-277.38); 5.61μg/day of vitamin B12 (95% CI 2.53-8.70), and 139.67 mg/day of vitamin C (95% CI 59.33-220.02). Mineral intake of 637.32 mg/day of calcium (95% CI 288.54-986.11) and 9 mg/day of iron (95% CI 2.28-15.71) was obtained. A low intake of fruits and vegetables was found.

CONCLUSION

Individuals with MCI and dementia from LAC have a nutritional deficiency characterized by a lower intake of fruits and vegetables, a high consumption of carbohydrates and protein, adequate fats intake and vitamins B12, vitamin C, and iron consumption, but a low intake of vitamin B9 and calcium.

Dietary calcium and magnesium intake and risk for incident dementia: The Shanghai Aging Study

Introduction

Calcium (Ca), magnesium (Mg), or the calcium to magnesium (Ca:Mg) ratio may affect the risk of dementia via complex mechanisms. The aim of this study was to evaluate the association of dietary Ca, Mg, and Ca:Mg ratio with dementia risk at the prospective phase of the Shanghai Aging Study.

Methods

We analyzed data from 1565 dementia-free participants living in an urban community who had measurements of dietary Ca and Mg intake derived from a food frequency questionnaire at baseline and incident dementia during follow-up.

Results

Over the 5-year follow-up, 162 (10.4%) participants were diagnosed with incident dementia by Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria. Participants with the lowest tertile of dietary Ca (<339.1 mg/day) and Mg (<202.1 mg/day) had the highest incidence rates of dementia (3.3/100 person-years for Ca, 3.3/100 person-years for Mg) compared to those with higher Ca and Mg intake. In the subgroup with Ca:Mg ratios ≤ 1.69, Mg intake >267.5 mg/day was related to an increased risk for dementia (adjusted hazard ratio: 3.97, 95% confidence interval: 1.29-12.25).

Conclusions

Our findings suggest that high dietary intake of Mg is associated with an increased risk of dementia mainly among older adults with low Ca:Mg intake ratios. Proper balance of Ca to Mg in the diet may be critical to the relationship between Mg intake and risk of dementia.

Highlights

Participants with the lowest tertile of dietary calcium (Ca) and magnesium (Mg) had the highest incidence rates of dementia.In the subgroup with Ca:Mg ratios ≤1.69, Mg intake >267.5 mg/day was related to an increased risk for dementia.Balance of Ca to Mg in diet may be critical to the relationship between Mg intake and risk of dementia.

Meta-analysis of sugar-sweetened beverage intake and the risk of cognitive disorders

BACKGROUND

Previous epidemiological studies revealed inconsistent associations between sugar-sweetened beverage (SSB) consumption and cognitive disorders, but there have been no meta-analyses of the pooled results. Thus, a meta-analysis was performed to determine the association between SSB consumption and cognitive disorders.

METHODS

A systematic search of the literature prior to May 20, 2022 was performed using the PubMed and Web of Science databases. Random effects models were used to calculate and combine odds ratios (ORs) depending on the degree of heterogeneity.

RESULTS

13 studies met the inclusion criteria. A total of 242,014 participants (2752 in three cross-sectional studies and 239,262 in ten cohort studies) were included. A random effects meta-analysis, according to the comprehensive analysis of SSB consumption, was associated with a greater prevalence of cognitive disorders (OR = 1.17, 95 % CI = 1.05-1.29; I² = 90.1 %). Subgroup analyses of study design, type of SSB, or cognitive disorders outcome was performed. In subgroup analyses, we found that SSB intake was associated with a higher prevalence of cognitive disorders in cohort studies, middle-aged and elderly population, and participants with sugar-sweetened soft drinks. However, no significant association was found in other subgroups.

CONCLUSION

Our results indicate that SSB intake is positively associated with the prevalence of cognitive disorders. Therefore, attention should be paid to reducing SSB intake as an early intervention for cognitive disorders.

Effects of magnesium valproate adjuvant therapy on patients with dementia: A systematic review and meta-analysis

BACKGROUND

Current research has found contradictory results on the treatment of magnesium valproate (VPM) in patients with dementia (PwD).

OBJECTIVES

Here, we conducted a meta-analysis to evaluate the efficacy and safety of VPM in the adjuvant treatment of PwD.

PURPOSE

Current research has found contradictory results on the treatment of VPM in PwD. Here, we conducted a meta-analysis to evaluate the efficacy and safety of VPM in the adjuvant treatment of PwD.

METHODS

MEDLINE via PubMed, Cochrane Library, EBSCO, Embase, China National Knowledge (CNKI), and Wan Fang databases were researched to gather relevant data on magnesium valproate assistant therapy for patients with dementia (PwD) by using medical subject headings and term words.

RESULTS

After the final screening, 22 RCT studies (a total of 1899 participants) were included in this meta-analysis, which compared VPM adjuvant treatment with antidementia or psychotropic drug monotherapy. Significant differences were found in the scores on mini-mental state examination (P = .028), Alzheimer disease assessment scale cognitive subscale (P < .05), Bech-Rafaelsen Mania Rating Scale (P < .05), behavioral pathology in Alzheimer disease rating scale (P = .001), activities of daily living (P < .05), and Pittsburgh Sleep Quality Index (P < .05). Besides, the levels of inflammatory factors including IL-1β, IL-6, and TNF-α were significantly lower than those in the monotherapy group (P < .05). While there was no increase in the incidence of adverse events (P = .383), VPM as an assistant therapy is generally well tolerated in PwD.

CONCLUSION

By meta-analysis, evidence was found to support VPM additional used for the treatment of cognitive function, psychiatric symptoms, or disease improvement in PwD. VPM may be a potential drug to aid in the treatment of dementia patients. However, there was lack of enough evidence to classification of dementia severity in our inclusion study. More research is still needed, including clinical trials evaluating VPM as a complementary therapy.

Association between magnesium intake and cognition in US older adults: National Health and Nutrition Examination Survey (NHANES) 2011 to 2014

INTRODUCTION

Identifying nutrition- and modifiable lifestyle-based risk factors for cognitive decline and dementia may contribute future primary prevention strategies. This study aimed to evaluate the associations between magnesium intake and cognition in older adults in the United States.

METHODS

Based on the National Health and Nutrition Survey (NHANES) between 2011 and 2014, the study included 2508 participants aged 60 years and older. Linear regression models were used to examine the association of total magnesium intake with cognition.

RESULTS

After adjusted demographic and other confounding factors, intakes of energy and total calcium, and serum vitamin D level, higher intake of total magnesium was independently associated with 0.15 higher global cognitive z-score (95% confidence interval, 0.02 to 0.28 for highest vs. lowest quartile, P trend = .037). The positive association of total magnesium intake with global cognition was primarily presented among women, non-Hispanic Whites, and those with sufficient serum vitamin D levels (≥50 nmol/L), although interactions were not significant. There were no clear linear associations for global cognition with serum vitamin D level.

DISCUSSIONS

Our findings suggest that high magnesium intake alone may improve cognition in older adults, particularly among non-Hispanic Whites and subjects with sufficient levels of serum vitamin D. Further studies are needed to confirm the findings.

Association of Circulating Magnesium Levels in Patients With Alzheimer's Disease From 1991 to 2021: A Systematic Review and Meta-Analysis

Alzheimer's disease (AD) remains a medical and social challenge worldwide. Magnesium (Mg) is one of the most frequently evaluated essential minerals with diverse biological functions in human body. However, the association between circulating Mg levels and AD remains controversial. We conducted a meta-analysis of 21 studies published between 1991 and 2021 to determine whether the Mg levels in the blood and cerebrospinal fluid (CSF) are abnormal in AD. Literatures were searched in PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang Data without language limitations. A pooled subject sample including 1,112 AD patients and 1,001 healthy controls (HCs) was available to assess Mg levels in serum and plasma; 284 AD patients and 117 HCs were included for Mg levels in CSF. It was found that serum and plasma levels of Mg were significantly reduced in AD patients compared with HCs (standardized mean difference [SMD] = -0.89; 95% confidence interval [CI] [-1.36, -0.43]; P = 0.000). There was statistically non-significant for Mg level in CSF between AD and HCs, whereas a decreased tendency were detected (SMD = -0.16; 95% CI [-0.50, 0.18]; P = 0.364). .In addition, when we analyzed the Mg levels of serum, plasma and CSF together, the circulating Mg levels in AD patients was significantly lower (SMD = -0.74, 95% CI [-1.13; -0.35]; P = 0.000). These results indicate that Mg deficiency may be a risk factor of AD and Mg supplementation may be a potentially valuable adjunctive treatment for AD. Systematic Review Registration: www.crd.york.ac.uk/PROSPERO/, registration number CRD42021254557.

Sex-Specific Associations of Dietary Iron Intake with Brain Iron Deposition on Imaging and Incident Dementia: A Prospective Cohort Study

OBJECTIVES

The study aimed to evaluate the association of dietary iron intake with incident dementia and brain iron deposition.

DESIGN/SETTING/PARTICIPANTS

We included dementia-free participants from the UK Biobank who completed at least one 24-hour dietary recall at study baseline (2009-2012) and were followed up to 2021. Incident dementia was determined through linkage to medical records and death registries. Brain MRI was conducted in a subgroup of participants since 2014, with T2* measurements being used as indicators of brain iron deposition.

MEASUREMENTS

Cox proportional hazard models were used to assess the associations of high (top quintile) and low (bottom quintile) versus medium (quintile 2 to 4) level of dietary iron intake with incident dementia, respectively. Linear regression was applied to assess the relations between dietary iron intake and brain T2* measurements.

RESULTS

During follow-up (mean = 9.5 years), a total of 1,454 participants (650 women and 804 men) developed dementia among 191,694 participants (55.0% female; mean age, 56.2 years). When adjusted for sociodemographic, lifestyle, and other dietary factors, participants with low dietary iron intake (< 10.05 mg/day) had a significantly higher dementia risk (hazard ratio [HR], 1.50, 95% confidence interval [CI], 1.19-1.89), while the relation for high intake (> 16.92 mg/day) was non-significant (HR, 1.16, 95% CI, 0.92-1.46). A significant gender difference (P-interaction < 0.001) was observed, with a U-shaped association in male participants (HR for low vs. medium, 1.56, 95% CI, 1.14-2.13; HR for high vs. medium, 1.39, 95% CI, 1.03 - 1.88; P-nonlinearity < 0.001) and no significant association in females, regardless of their menopause status. In general, dietary iron intake was not related to T2* measurements of iron deposition in most brain regions.

CONCLUSION

Our findings suggested a U-shape relationship between dietary iron intake and risk of dementia among males, but not females.

Protocol of the Healthy Brain Study: An accessible resource for understanding the human brain and how it dynamically and individually operates in its bio-social context

The endeavor to understand the human brain has seen more progress in the last few decades than in the previous two millennia. Still, our understanding of how the human brain relates to behavior in the real world and how this link is modulated by biological, social, and environmental factors is limited. To address this, we designed the Healthy Brain Study (HBS), an interdisciplinary, longitudinal, cohort study based on multidimensional, dynamic assessments in both the laboratory and the real world. Here, we describe the rationale and design of the currently ongoing HBS. The HBS is examining a population-based sample of 1,000 healthy participants (age 30–39) who are thoroughly studied across an entire year. Data are collected through cognitive, affective, behavioral, and physiological testing, neuroimaging, bio-sampling, questionnaires, ecological momentary assessment, and real-world assessments using wearable devices. These data will become an accessible resource for the scientific community enabling the next step in understanding the human brain and how it dynamically and individually operates in its bio-social context. An access procedure to the collected data and bio-samples is in place and published on https://www.healthybrainstudy.nl/en/data-and-methods/access.

Trail registration:https://www.trialregister.nl/trial/7955.

Association between serum iron concentrations and cognitive impairment in older adults aged 60 years and older: A dose-response analysis of National Health and Nutrition Examination Survey

Epidemiological evidence on peripheral iron and cognitive impairment in older adults is sparse and limited. Results on serum iron and cognitive impairment in older adults from the National Health and Nutrition Examination Survey have not been reported. Data on serum iron and cognitive impairment from individuals ≥ 60 years of age were obtained from the 2011–2014 NHANES (N = 3,131). Serum iron concentrations were determined with DcX800 method. Cognitive impairment was assessed with four cognitive tests: the Digit Symbol Substitution Test (DSST), the Animal Fluency (AF), the Consortium to Establish a Registry for Alzheimer’s Disease Delayed Recall (CERAD-DR) and Word Learning (CERAD-WL) tests. Logistic regression and restricted cubic splines were adopted to explore the dose-response relationship between serum iron concentrations and cognitive impairment. Comparing the highest to lowest tertile of serum iron concentrations, the multivariate-adjusted odds ratios of scoring low on the DSST were 0.70 (0.49–1.00), 0.88 (0.65–1.20) for CERAD-WL, 0.65 (0.48–0.88) for CERAD-DR, and 0.78 (0.53–1.15) for AF. Stratified analyses by sex showed that the above-mentioned associations were mainly found in men; however, the interaction with sex was not significant. Dose-response analysis showed that relationships between serum iron and cognitive impairment evaluated by DSST and CERAD-DR were linear, respectively.

The Association of Essential Metals with APOE Genotype in Alzheimer's Disease

BACKGROUND

The major confirmed genetic risk factor for late-onset, sporadic Alzheimer's disease (AD) is variant ɛ4 of apolipoprotein E gene (APOE). It is proposed that ApoE, a protein involved in transport of cholesterol to neurons can cause neurodegeneration in AD through interaction with metals. Previous studies mostly associated copper, iron, zinc, and calcium with ApoE4-mediated toxicity.

OBJECTIVE

To test the association of essential metals with APOE genotype.

METHODS

We compared plasma and cerebrospinal fluid (CSF) levels of copper, zinc, iron, sodium, magnesium, calcium, cobalt, molybdenum, manganese, boron, and chromium, and CSF ferritin levels among AD, mild cognitive impairment (MCI) patients, and healthy controls (HC) with different APOE genotype.

RESULTS

Sodium, copper, and magnesium levels were increased in carriers of ɛ4 allele. Additionally, the increase in sodium, calcium and cobalt plasma levels was observed in carriers of ɛ4/ɛx genotype. The decrease in boron plasma levels was observed in carriers of ɛ4 allele and ɛ4/ɛ4 genotype. Additionally, CSF zinc levels as well as plasma sodium levels were increased in AD patients compared to HC.

CONCLUSION

These results indicate that the molecular underpinnings of association of essential metals and metalloids with APOE should be further tested and clarified in vivo and in vitro.

Associations between vitamin E, oxidative stress markers, total homocysteine levels, and physical activity or cognitive capacity in older adults

This study examined the associations between vitamin E, oxidative stress markers, total homocysteine levels, and physical activity or cognitive capacity in older adults. One hundred and six older adults (62 men, 44 women) within the age range of 56-81 years participated. The Global Physical Activity Questionnaire and the Loewenstein Occupational Therapy Cognitive Assessment were used to assess physical activity and cognitive function, respectively. Vitamin E (e.g., α-tocopherol and γ-tocopherol), oxidative stress markers (e.g., total antioxidant capacity and nitric oxide), and total homocysteine were estimated. There were significant associations between physical activity (high versus moderate versus poor) and all biomarkers (all p = 0.000, and p = 0.010 for γ-tocopherol). While total homocysteine and total antioxidant capacity were significantly associated with cognitive capacity (p = 0.000), vitamin E levels (e.g., α-tocopherol and γ-tocopherol) and nitric oxide (p = 0.354, 0.103 and 0.060, respectively) were not related to cognitive capacity in older adults. This study concludes that physical activity was associated with Vitamin E, oxidative stress markers, total homocysteine, and cognitive capacity in older adults. Although cognitive capacity was associated with total homocysteine and total antioxidant capacity, it was unrelated to vitamin E levels and nitric oxide in older adults.

Plasma Concentrations of Magnesium and Risk of Dementia: A General Population Study of 102 648 Individuals

BACKGROUND

Low and high concentrations of plasma magnesium are associated with increased risk of future all-cause dementia; however, the underlying reasons remain elusive. The magnesium ion is an important electrolyte serving as a cofactor in many enzymatic processes in the human organism. Magnesium affects both neuronal and vascular functions. We investigated the associations of plasma concentrations of magnesium associate with common subtypes of dementia as Alzheimer dementia and non-Alzheimer dementia, and potential pathways by which magnesium may affect risk of dementia.

METHODS

Plasma concentrations of magnesium were measured in 102 648 individuals from the Copenhagen General Population Study. Cox regression and natural effects mediation analyses evaluated associations with either Alzheimer dementia or non-Alzheimer dementia.

RESULTS

Multifactorially adjusted hazard ratios for non-Alzheimer dementia were 1.50(95% confidence interval (CI):1.21-1.87) for the lowest and 1.34(1.07-1.69) for the highest vs the fourth quintile (reference) of plasma magnesium concentrations. Diabetes, cumulated smoking, stroke, and systolic blood pressure mediated 10.4%(3.1-22.8%), 6.8%(1.2-14.0%), 1.3%(0.1-3.6%), and 1.0%(0.2-2.6%), respectively, in the lowest quintile, whereas stroke mediated 3.2%(0.4-11.9%) in the highest quintile. No associations were observed for Alzheimer dementia.

CONCLUSIONS

Low and high plasma magnesium concentrations were associated with high risk of vascular-related non-Alzheimer dementia, with the lowest risk observed at a concentration of 2.07 mg/dL (0.85 mmol/L). No association was observed for Alzheimer dementia. Mediation analysis suggested that diabetes may be in the causal pathway between low plasma magnesium concentrations and high risk of non-Alzheimer dementia, while cumulated smoking, stroke, and systolic blood pressure played minor mediating roles.

A Fundamental Role for Oxidants and Intracellular Calcium Signals in Alzheimer's Pathogenesis-And How a Comprehensive Antioxidant Strategy May Aid Prevention of This Disorder

Oxidative stress and increased cytoplasmic calcium are key mediators of the detrimental effects on neuronal function and survival in Alzheimer's disease (AD). Pathways whereby these perturbations arise, and then prevent dendritic spine formation, promote tau hyperphosphorylation, further amplify amyloid β generation, and induce neuronal apoptosis, are described. A comprehensive program of nutraceutical supplementation, comprised of the NADPH oxidase inhibitor phycocyanobilin, phase two inducers, the mitochondrial antioxidant astaxanthin, and the glutathione precursor N-acetylcysteine, may have important potential for antagonizing the toxic effects of amyloid β on neurons and thereby aiding prevention of AD. Moreover, nutraceutical antioxidant strategies may oppose the adverse impact of amyloid β oligomers on astrocyte clearance of glutamate, and on the ability of brain capillaries to export amyloid β monomers/oligomers from the brain. Antioxidants, docosahexaenoic acid (DHA), and vitamin D, have potential for suppressing microglial production of interleukin-1β, which potentiates the neurotoxicity of amyloid β. Epidemiology suggests that a health-promoting lifestyle, incorporating a prudent diet, regular vigorous exercise, and other feasible measures, can cut the high risk for AD among the elderly by up to 60%. Conceivably, complementing such lifestyle measures with long-term adherence to the sort of nutraceutical regimen outlined here may drive down risk for AD even further.

Association of magnesium intake and vitamin D status with cognitive function in older adults: an analysis of US National Health and Nutrition Examination Survey (NHANES) 2011 to 2014

PURPOSE

Reduced cognitive function associated with aging has gained increasing attention as the US population ages. Magnesium plays a critical role in vitamin D biosynthesis and metabolism; and deficiencies in magnesium and vitamin D show associations with poor cognition. However, no study has examined their interaction. This study aimed to evaluate the associations of magnesium intake and serum 25-hydroxyvitamin D (25(OH)D) concentrations, indicating vitamin D status, with cognition, and interaction between these nutrients in older adults.

METHODS

Based on the National Health and Nutrition Survey (NHANES) 2011-2014, the study included 2466 participants aged ≥ 60 years who completed the Digit Symbol Substitution Test (DSST) and had data available on serum 25(OH)D and magnesium intake. Cognitive impairment was defined as a DSST score lower than the lowest quartile. Serum 25(OH)D concentrations were measured by HPLC-tandem mass spectrometry.

RESULTS

Higher total magnesium intake was independently associated with higher DSST scores (highest quartile vs lowest: β = 4.34, 95% CI 1.14-7.54). The association of total magnesium intake with high DSST score was primarily observed among women, non-Hispanic whites, physically active participants and those with sufficient vitamin D status, although the interactions were not significant. The odds of cognitive impairment was reduced with increasing intake of total magnesium (p trend < 0.01) and higher level of serum 25(OH)D (p trend = 0.05).

CONCLUSIONS

Findings suggest that high magnesium intake alone may improve cognitive function in older adults, and the association may be stronger among subjects with sufficient vitamin D status. Further studies are needed to confirm these findings.

Magnesium in Aging, Health and Diseases

Several changes of magnesium (Mg) metabolism have been reported with aging, including diminished Mg intake, impaired intestinal Mg absorption and renal Mg wasting. Mild Mg deficits are generally asymptomatic and clinical signs are usually non-specific or absent. Asthenia, sleep disorders, hyperemotionality, and cognitive disorders are common in the elderly with mild Mg deficit, and may be often confused with age-related symptoms. Chronic Mg deficits increase the production of free radicals which have been implicated in the development of several chronic age-related disorders. Numerous human diseases have been associated with Mg deficits, including cardiovascular diseases, hypertension and stroke, cardio-metabolic syndrome and type 2 diabetes mellitus, airways constrictive syndromes and asthma, depression, stress-related conditions and psychiatric disorders, Alzheimer's disease (AD) and other dementia syndromes, muscular diseases (muscle pain, chronic fatigue, and fibromyalgia), bone fragility, and cancer. Dietary Mg and/or Mg consumed in drinking water (generally more bioavailable than Mg contained in food) or in alternative Mg supplements should be taken into consideration in the correction of Mg deficits. Maintaining an optimal Mg balance all through life may help in the prevention of oxidative stress and chronic conditions associated with aging. This needs to be demonstrated by future studies.

Serum Magnesium and Cognitive Function Among Qatari Adults

Background: Previous studies found that low blood magnesium increases the risk of several diseases such as cardiovascular diseases (CVD), diabetes, and hypertension. These ailments are associated with declined cognitive function.

Objective: We aimed to examine the association between serum magnesium and cognitive function among Qatari adults. In addition, we assessed the interaction relation between low serum magnesium, hypertension, and diabetes in relation to cognitive function.

Method: Data from 1,000 Qatari participants aged ≥20 years old who participated in the Qatar Biobank (QBB) Study were analyzed. Serum magnesium was measured by an automated calorimetric method and suboptimal magnesium was characterized by <0.85 mmol/l. Cognitive function was determined by measuring the mean reaction time (MRT) based on a computer-based, self-administered test. Multivariable linear regression was used to examine the relation between serum magnesium concentrations and cognitive function.

Results: The prevalence of suboptimal magnesium was 57.1%. Across the four quartiles of serum magnesium from the lowest to the highest, the regression coefficients (95% CI) for MRT were 0 (reference), −17.8, −18.3, and −31.9 (95% CI 2.4–3.1; p for trend 0.05). The presence of hypertension and diabetes significantly increased the MRT. Women with suboptimal magnesium and hypertension had the highest MRT.

Conclusion: The prevalence of suboptimal magnesium is high in Qatar. There was a direct association between serum magnesium and cognitive function. Low magnesium concentrations were associated with a longer MRT.

Lifestyle Modifications and Nutritional Interventions in Aging-Associated Cognitive Decline and Alzheimer's Disease

Alzheimer's disease (AD) is a type of incurable neurodegenerative disease that is characterized by the accumulation of amyloid-β (Aβ; plaques) and tau hyperphosphorylation as neurofibrillary tangles (NFTs) in the brain followed by neuronal death, cognitive decline, and memory loss. The high prevalence of AD in the developed world has become a major public health challenge associated with social and economic burdens on individuals and society. Due to there being limited options for early diagnosis and determining the exact pathophysiology of AD, finding effective therapeutic strategies has become a great challenge. Several possible risk factors associated with AD pathology have been identified; however, their roles are still inconclusive. Recent clinical trials of the drugs targeting Aβ and tau have failed to find a cure for the AD pathology. Therefore, effective preventive strategies should be followed to reduce the exponential increase in the prevalence of cognitive decline and dementia, especially AD. Although the search for new therapeutic targets is a great challenge for the scientific community, the roles of lifestyle interventions and nutraceuticals in the prevention of many metabolic and neurodegenerative diseases are highly appreciated in the literature. In this article, we summarize the molecular mechanisms involved in AD pathology and the possible ameliorative action of lifestyle and nutritional interventions including diet, exercise, Calorie restriction (CR), and various bioactive compounds on cognitive decline and dementia. This article will provide insights into the role of non-pharmacologic interventions in the modulation of AD pathology, which may offer the benefit of improving quality of life by reducing cognitive decline and incident AD.

Seeds

A wide variety of plant species provide edible seeds. Seeds are the dominant source of human calories and protein. The most important and popular seed food sources are cereals, followed by legumes and nuts. Their nutritional content of fiber, protein, and monounsaturated/polyunsaturated fats make them extremely nutritious. They are important additions to our daily food consumption. When consumed as part of a healthy diet, seeds can help reduce blood sugar, cholesterol, and blood pressure.

Dairy, soy, and calcium consumption and risk of cognitive impairment: the Singapore Chinese Health Study

PURPOSE

It is unclear if midlife consumption of dairy and soy food intake, and their components of calcium and isoflavones (in soy), is related to cognitive impairment in elderly.

METHODS

We used baseline data on lifestyle and habitual diet of 16,948 participants collected during their recruitment into the Singapore Chinese Health Study from 1993 to 1998, and data on their cognitive function, measured using a 30-item Singapore modified Mini-Mental State Examination, during follow-up interviews from 2014 to 2016. We used multivariable logistic regression models to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for developing cognitive impairment.

RESULTS

Higher dairy intake was associated with a lower risk of cognitive impairment in a dose-dependent manner (P for trend = 0.009). Compared to the lowest quartile of dairy intake, ORs (95% CIs) were 0.93 (0.81-1.07) for the second, 0.88 (0.76-1.01) for the third, and 0.82 (0.72-0.94) for the fourth quartiles of intake. Similar results were found for dairy calcium intake (P for trend = 0.008). However, there was no statistically significant association for intake of soy (OR comparing extreme quartiles 0.99, 95% CI 0.87-1.14, P for trend = 0.92), isoflavones (OR 1.01, 95% CI 0.88-1.15, P for trend = 0.90) or non-dairy calcium (OR 1.06, 95% CI 0.86-1.30, P for trend = 0.81) with risk of cognitive impairment.

CONCLUSIONS

Dairy intake at midlife could have a protective association against cognitive impairment that may not be attributed to its calcium content alone, while soy or isoflavone intake was not associated with the cognition of elderly in our study.

Serum Potassium Is Associated with Cognitive Decline in Patients with Lewy Body Dementia

BACKGROUND

Epidemiological studies link serum potassium (K+) to cognitive performance, but whether cognitive prognosis in dementia is related to K+ levels is unknown.

OBJECTIVE

To determine if K+ levels predict cognitive prognosis in dementia and if this varies according to diagnosis or neuropathological findings.

METHODS

This longitudinal cohort study recruited 183 patients with mild Alzheimer's disease or Lewy body dementia (LBD). Serum K+ and eGFR were measured at baseline and medications which could affect K+ registered. The Mini-Mental State Examination (MMSE) was measured annually over 5 years, and mortality registered. Association between K+ and √(30 -MMSE) was estimated overall, and according to diagnosis (joint model). Associations between MMSE-decline and K+ were assessed in two subgroups with neuropathological examination (linear regression) or repeated measurements of K+ over 3 years (mixed model).

RESULTS

Serum K+ at baseline was associated with more errors on MMSE over time (Estimate 0.18, p = 0.003), more so in LBD (p = 0.048). The overall association and LBD interaction were only significant in the 122 patients not using K+ relevant medication. Repeated K+ measures indicated that the association with MMSE errors over time was due to a between-person effect (p < 0.05, n = 57). The association between the annual MMSE decline was stronger in patients with autopsy confirmed LBD and more α-synuclein pathology (all: p < 0.05, n = 41).

CONCLUSION

Higher serum K+ predicts poorer cognitive prognosis in demented patients not using medications which affect K+, likely a between-person effect seen mainly in LBD.

Mineral Nutrition and the Risk of Chronic Diseases: A Mendelian Randomization Study

We applied Mendelian randomization analyses to investigate the potential causality between blood minerals (calcium, magnesium, iron, copper, and zinc) and osteoporosis (OP), gout, rheumatoid arthritis (RA), type 2 diabetes (T2D), Alzheimer’s disease (AD), bipolar disorder (BD), schizophrenia, Parkinson’s disease and major depressive disorder. Single nucleotide polymorphisms (SNPs) that are independent (r² < 0.01) and are strongly related to minerals (p < 5 × 10⁻⁸) are selected as instrumental variables. Each standard deviation increase in magnesium (0.16 mmol/L) is associated with an 8.94-fold increase in the risk of RA (p = 0.044) and an 8.78-fold increase in BD (p = 0.040) but a 0.10 g/cm² increase in bone density related to OP (p = 0.014). Each per-unit increase in copper is associated with a 0.87-fold increase in the risk of AD (p = 0.050) and BD (p = 0.010). In addition, there is suggestive evidence that calcium is positively correlated (OR = 1.36, p = 0.030) and iron is negatively correlated with T2D risk (OR = 0.89, p = 0.010); both magnesium (OR = 0.26, p = 0.013) and iron (OR = 0.71, p = 0.047) are negatively correlated with gout risk. In the sensitivity analysis, causal estimation is not affected by pleiotropy. This study supports the long-standing hypothesis that magnesium supplementation can increase RA and BD risks and decrease OP risk and that copper intake can reduce AD and BD risks. This study will be helpful to address some controversial debates on the relationships between minerals and chronic diseases.

More evidence is needed. Iron, incident cognitive decline and dementia: a systematic review

Background

Our aim was to systematically review the relationship between iron and incident cognitive decline or dementia from midlife onwards.

Methods

Systematic review of eligible studies using Medline, Embase and PsycINFO^® for the period from 1 January 1986 to 2 December 2016 (CRD42016023800), where study populations had a mean age of over 50 years and were free of cognitive impairment or dementia at baseline. Two authors independently extracted data according to eligibility criteria and assessed study characteristics, quality and outcomes. Disagreement was resolved by discussion.

Results

A total of 1185 relevant records were identified with 12 full-text articles eligible for review. Six studies were excluded, leaving six texts to be included. Sample size ranged from 90 to 7173, with an average follow up of approximately 11.5 years. Baseline iron measures included brain iron (n = 2), iron-related biomarkers in blood and plasma (n = 2), and iron intake estimates from dietary records (n = 2). Outcomes were dementia incidence (n = 2) and longitudinal outcomes on neuropsychological tests (n = 4). Bias was evident across studies in one or more of the following: recruitment, iron exposure, outcome assessments, potential confounders, missing data or attrition.

Conclusions

Diversity across the small number of identified studies precludes conclusions regarding the role of iron in cognitive decline or dementia. Our review highlights substantial gaps in the evidence base and the need for more comprehensive, higher quality studies in this area.

The Role of Magnesium in Neurological Disorders

Magnesium is well known for its diverse actions within the human body. From a neurological standpoint, magnesium plays an essential role in nerve transmission and neuromuscular conduction. It also functions in a protective role against excessive excitation that can lead to neuronal cell death (excitotoxicity), and has been implicated in multiple neurological disorders. Due to these important functions within the nervous system, magnesium is a mineral of intense interest for the potential prevention and treatment of neurological disorders. Current literature is reviewed for migraine, chronic pain, epilepsy, Alzheimer’s, Parkinson’s, and stroke, as well as the commonly comorbid conditions of anxiety and depression. Previous reviews and meta-analyses are used to set the scene for magnesium research across neurological conditions, while current research is reviewed in greater detail to update the literature and demonstrate the progress (or lack thereof) in the field. There is strong data to suggest a role for magnesium in migraine and depression, and emerging data to suggest a protective effect of magnesium for chronic pain, anxiety, and stroke. More research is needed on magnesium as an adjunct treatment in epilepsy, and to further clarify its role in Alzheimer’s and Parkinson’s. Overall, the mechanistic attributes of magnesium in neurological diseases connote the macromineral as a potential target for neurological disease prevention and treatment.

The Link between Potassium and Mild Cognitive Impairment in Mexican-Americans

Background

Recent evidence suggests that increasing dietary intake of minerals reduces the risk of dementia. This study aimed to examine the relationship between potassium and diagnosis of mild cognitive impairment (MCI) in a sample of older Mexican-Americans from rural and urban populations.

Methods

The sample was formed of a total of 139 participants with MCI and 371 normal controls from two independent cohorts: a rural cohort (Facing Rural Obstacles to Healthcare Now through Intervention, Education and Research [Project FRONTIER]) and an urban cohort (the Health and Aging Brain among Latino Elders [HABLE] study). Serum electrolytes examined were sodium and potassium. Age and education were entered in the model as covariates.

Results

Across both cohorts, the Project FRONTIER (OR = 3.1; p = 0.01) and the HABLE Project (OR = 2.0; p = 0.04), the results indicated that serum potassium levels significantly increased the risk of diagnosis of MCI.

Conclusion

Our finding suggested a link between serum potassium levels and a diagnosis of MCI in Mexican-Americans. The results of this study support a previous research which has suggested that the risk factors for MCI may vary by ethnicity.

Dietary Sodium/Potassium Intake Does Not Affect Cognitive Function or Brain Imaging Indices

BACKGROUND

Dietary sodium may influence cognitive function through its effects on cerebrovascular function and cerebral blood flow.

METHODS

The aim of this study was to evaluate the association of dietary sodium intake with cognitive decline in community-dwelling older adults. We also evaluated the associations of dietary potassium and sodium:potassium intake with cognitive decline, and associations of these nutrients with micro- and macro-structural brain magnetic resonance imaging (MRI) indices. In all, 1,194 participants in the Health Aging and Body Composition study with measurements of dietary sodium intake (food frequency questionnaire [FFQ]) and change in the modified Mini Mental State Exam (3MS) were included.

RESULTS

The age of participants was 74 ± 3 years with a mean dietary sodium intake of 2,677 ± 1,060 mg/day. During follow-up (6.9 ± 0.1 years), 340 (28%) had a clinically significant decline in 3MS score (≥1.5 SD of mean decline). After adjustment, dietary sodium intake was not associated with odds of cognitive decline (OR 0.96, 95% CI 0.50-1.84 per doubling of sodium). Similarly, potassium was not associated with cognitive decline; however, higher sodium:potassium intake was associated with increased odds of cognitive decline (OR 2.02 [95% CI 1.01-4.03] per unit increase). Neither sodium or potassium alone nor sodium:potassium were associated with micro- or macro-structural brain MRI indices. These results are limited by the use of FFQ.

CONCLUSIONS

In community-dwelling older adults, higher sodium:potassium, but not sodium or potassium intake alone, was associated with decline in cognitive function, with no associations observed with micro- and macro-structural brain MRI indices. These findings do not support reduction dietary sodium/increased potassium intake to prevent cognitive decline with aging.

Nutrition and risk of dementia: overview and methodological issues

After two decades of research on nutrition and dementia there is strong evidence for preventive effects of vitamin E, B vitamins, and n-3 fatty acids and deleterious effects of saturated fat on dementia. Among specific foods with evidence of neuroprotection are green leafy vegetables, other vegetables, berries, and seafood. A number of studies have examined dietary patterns, particularly the Mediterranean diet and DASH (Dietary Approaches to Stop Hypertension), neither of which is tailored to the specific foods and nutrients that have been identified as neuroprotective. A new diet called MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) incorporates many elements of the Mediterranean diet and DASH but with modifications that reflect current evidence for brain neuroprotection. The evidence in support of the relation of various nutrients and the Mediterranean diet to dementia has been inconsistent. The inconsistencies may be explained by inattention to nutrient/food intake levels in the interpretation of study findings and trial design, including a shifting metric among studies for scoring adherence to the Mediterranean diet. Future studies should pay particular attention to levels of intake in the design and analyses of nutritional studies.

Magnesium Status in Alzheimer's Disease: A Systematic Review

The interest in poor magnesium (Mg) status as risk factor for Alzheimer's disease (AD) is increasing due to its antioxidant and neuroprotective properties. A systematic PubMed literature search of studies investigating Mg status was undertaken comparing AD to healthy controls (HCs) or patients with medical illness (medical controls [MCs]). Standardized mean differences (SMDs) ± 95% confidence intervals (CIs) were calculated for all outcomes. Of 192 potentially eligible studies, 13 were included (559 patients with AD, 381 HCs, and 126 MCs). Compared to HCs, patients with AD had significantly lower Mg in cerebrospinal fluid (2 studies; SMD = -0.35;P= .02) and in hair (2 studies; SMD = -0.75;P= .0001). No differences between AD and controls were evident for serum Mg. In conclusion, AD seems to be associated with a lower Mg status when compared to HCs, while the scarcity of studies limited the findings about MCs.

Magnesium in Prevention and Therapy

Magnesium is the fourth most abundant mineral in the body. It has been recognized as a cofactor for more than 300 enzymatic reactions, where it is crucial for adenosine triphosphate (ATP) metabolism. Magnesium is required for DNA and RNA synthesis, reproduction, and protein synthesis. Moreover, magnesium is essential for the regulation of muscular contraction, blood pressure, insulin metabolism, cardiac excitability, vasomotor tone, nerve transmission and neuromuscular conduction. Imbalances in magnesium status—primarily hypomagnesemia as it is seen more common than hypermagnesemia—might result in unwanted neuromuscular, cardiac or nervous disorders. Based on magnesium’s many functions within the human body, it plays an important role in prevention and treatment of many diseases. Low levels of magnesium have been associated with a number of chronic diseases, such as Alzheimer’s disease, insulin resistance and type-2 diabetes mellitus, hypertension, cardiovascular disease (e.g., stroke), migraine headaches, and attention deficit hyperactivity disorder (ADHD).

Dietary Patterns Derived by Cluster Analysis are Associated with Cognitive Function among Korean Older Adults

The objective of this study was to investigate major dietary patterns among older Korean adults through cluster analysis and to determine an association between dietary patterns and cognitive function. This is a cross-sectional study. The data from the Korean Multi-Rural Communities Cohort Study was used. Participants included 765 participants aged 60 years and over. A quantitative food frequency questionnaire with 106 items was used to investigate dietary intake. The Korean version of the MMSE-KC (Mini-Mental Status Examination-Korean version) was used to assess cognitive function. Two major dietary patterns were identified using K-means cluster analysis. The "MFDF" dietary pattern indicated high consumption of Multigrain rice, Fish, Dairy products, Fruits and fruit juices, while the "WNC" dietary pattern referred to higher intakes of White rice, Noodles, and Coffee. Means of the total MMSE-KC and orientation score of the participants in the MFDF dietary pattern were higher than those of the WNC dietary pattern. Compared with the WNC dietary pattern, the MFDF dietary pattern showed a lower risk of cognitive impairment after adjusting for covariates (OR 0.64, 95% CI 0.44-0.94). The MFDF dietary pattern, with high consumption of multigrain rice, fish, dairy products, and fruits may be related to better cognition among Korean older adults.