RESUMO
Sufficient vitamin D status is crucial for successful pregnancy and fetal development. The assessment of 25-hydroxyvitamin D (25(OH)D) concentrations is commonly used to evaluate vitamin D status. Our objective was to examine the interrelated biodynamics of maternal and neonatal total, free and bioavailable 25(OH)D in maternal-neonatal dyads at birth and their associations with homeostasis and neonatal birth anthropometry. We analysed a cohort of seventy full-term mother-child pairs. We found positive associations between all neonatal measures of vitamin D status. Maternal forms exhibited a similar pattern of association, except for the bioavailable maternal form. In multivariate analysis, both total and free maternal 25(OH)D concentrations were correlated with all neonatal forms (neonatal total 25(OH)D: 1·29 (95 % CI, 1·12, 1·46) for maternal total 25(OH)D, 10·89 (8·16, 13·63) for maternal free 25(OH)D), (neonatal free 25(OH)D: 0·15 for maternal total 25(OH)D, 1·28 (95 % CI, 0·89, 1·68) for maternal free 25(OH)D) and (0·13 (95 % CI, 0·10, 0·16), 1·06 (95 % CI, 0·68, 1·43) for maternal free 25(OH)D), respectively, with the exclusion of the bioavailable maternal form. We observed no significant interactions within or between groups regarding maternal and neonatal vitamin D parameters and maternal calcium and parathyroid hormone concentrations, and neonatal birth anthropometry. Our study indicates that bioavailable maternal and neonatal 25(OH)D have no significant effects on vitamin D equilibrium, Ca homeostasis and neonatal anthropometry at birth. However, we observed an interaction between maternal and neonatal total and free 25(OH)D concentrations at the maternal-neonatal interface, with no associations observed with other calciotropic or anthropometric outcomes.
Assuntos
Cálcio , Deficiência de Vitamina D , Vitamina D/análogos & derivados , Gravidez , Recém-Nascido , Feminino , Humanos , Calcifediol , Vitaminas , Cálcio da Dieta , Antropometria , Relações Mãe-FilhoRESUMO
Vitamin D, known for its essential role in calcium and bone homeostasis, has multiple effects beyond the skeleton, including regulation of immunity and modulation of autoimmune processes. Several reports have shown suboptimal serum 25 hydroxyvitamin D [25(OH)D] levels in people with different inflammatory and autoimmune rheumatic conditions, and an association between 25(OH)D levels, disease activity and outcomes. Although most available data pertain to adults, insights often are extended to children. Juvenile rheumatic diseases (JRDs) are a significant health problem during growth because of their complex pathogenesis, chronic nature, multisystemic involvement, and long-term consequences. So far, there is no definitive or clear evidence to confirm the preventive or therapeutic effect of vitamin D supplementation in JRDs, because results from randomized controlled trials (RCTs) have produced inconsistent outcomes. This review aims to explore and discuss the potential role of vitamin D in treating selected JRDs. Medline/PubMed, EMBASE, and Scopus were comprehensively searched in June 2023 for any study on vitamin D supplementary role in treating the most common JRDs. We used the following keywords: "vitamin D" combined with the terms "juvenile idiopathic arthritis", "juvenile systemic scleroderma", "juvenile systemic lupus erythematosus", "juvenile inflammatory myopathies", "Behcet disease", "periodic fever syndromes" and "juvenile rheumatic diseases". Observational studies have found that serum 25(OH)D concentrations are lower in juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, juvenile systemic scleroderma, Behcet disease and proinflammatory cytokine concentrations are higher. This suggests that vitamin D supplementation might be beneficial, however, current data are insufficient to confirm definitively the complementary role of vitamin D in the treatment of JRDs. Considering the high prevalence of vitamin D deficiency worldwide, children and adolescents should be encouraged to supplement vitamin D according to current recommendations. More interventional studies, especially well-designed RCTs, assessing the dose-response effect and adjuvant effect in specific diseases, are needed to determine the potential significance of vitamin D in JRDs treatment.
Assuntos
Artrite Juvenil , Lúpus Eritematoso Sistêmico , Doenças Reumáticas , Escleroderma Sistêmico , Deficiência de Vitamina D , Adolescente , Criança , Humanos , Artrite Juvenil/complicações , Lúpus Eritematoso Sistêmico/complicações , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/complicações , Escleroderma Sistêmico/complicações , Vitaminas/uso terapêuticoRESUMO
The genomic era continues to revolutionize our understanding of the evolution of biodiversity. In phycology, emphasis remains on assembling nuclear and organellar genomes, leaving the full potential of genomic datasets to answer long-standing questions about the evolution of biodiversity largely unexplored. Here, we used whole-genome sequencing (WGS) datasets to survey species diversity in the kelp genus Alaria, compare phylogenetic signals across organellar and nuclear genomes, and specifically test whether phylogenies behave like trees or networks. Genomes were sequenced from across the global distribution of Alaria (including Alaria crassifolia, A. praelonga, A. crispa, A. marginata, and A. esculenta), representing over 550 GB of data and over 2.2 billion paired reads. Genomic datasets retrieved 3,814 and 4,536 single-nucleotide polymorphisms (SNPs) for mitochondrial and chloroplast genomes, respectively, and upwards of 148,542 high-quality nuclear SNPs. WGS revealed an Arctic lineage of Alaria, which we hypothesize represents the synonymized taxon A. grandifolia. The SNP datasets also revealed inconsistent topologies across genomic compartments, and hybridization (i.e., phylogenetic networks) between Pacific A. praelonga, A. crispa, and putative A. grandifolia, and between some lineages of the A. marginata complex. Our analysis demonstrates the potential for WGS data to advance our understanding of evolution and biodiversity beyond amplicon sequencing, and that hybridization is potentially an important mechanism contributing to novel lineages within Alaria. We also emphasize the importance of surveying phylogenetic signals across organellar and nuclear genomes, such that models of mixed ancestry become integrated into our evolutionary and taxonomic understanding.
Assuntos
Genoma de Cloroplastos , Genoma Mitocondrial , Kelp , Sequência de Bases , Hibridização Genética , Kelp/classificação , Kelp/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sequenciamento Completo do GenomaRESUMO
One of the major drivers of amphibian population declines is Batrachochytrium dendrobatidis (Bd). We sought to identify the major environmental drivers of Bd prevalence in Texas, USA, by drawing results from museum specimens. We sampled one of the largest museum collections in Texas, the Biodiversity Research and Teaching Collections at Texas A&M University. Our sampling focused on the 9 amphibian species with the widest geographical distribution within the state, where we sub-sampled 30% of each species per decade from 1930 to present via skin swabs, totaling 1501 independent sampling events, and used quantitative real-time PCR (qPCR) to detect pathogen presence. We analyzed several geo-referenced variables describing climatic conditions to identify potential factors influencing the likelihood of presence of Bd using boosted regression trees. Our final model suggests the most influential variables are mean temperature of driest quarter, annual mean temperature, temperature annual range, and mean diurnal range. The most likely suitable range for Bd is currently found in the Blackland Prairie and Cross Timbers ecoregions. Results of our future (to the year 2040) projections suggest that Bd could expand its current distribution. Our model could play an important role when developing an integrated conservation plan through (1) focusing future field work on locations with a high likelihood of presence, (2) assisting in the choice of locations for restoration, and (3) developing future research plans including those necessary for projecting reactions to climate change. Our model also could integrate new presence data of Bd when they become available to enhance prediction precision.
Assuntos
Quitridiomicetos , Anfíbios , Animais , Batrachochytrium , Mudança Climática , Texas/epidemiologiaRESUMO
Development of the Pasture and Cattle Management (PCM) method is a priority to control the cattle tick, Rhipicephalus australis, in New Caledonia. The PCM method provides the foundation for sustainable integrated tick control because approximately 95% of cattle ticks in infested pastures are off the host in the non-parasitic life stages, and the practice of treating cattle intensely with chemical acaricides is a risk for the emergence of resistance to these active ingredients in commercial acaricidal products available for veterinary use. Here, we report the findings of an assessment survey to document the utility of the PCM method. Analyses of questionnaire data provided by 21 beef cattle producers describing their management of 37 herds informed how to (1) assess the ability of PCM to reduce acaricide use and (2) prioritize best practices and define recommendations to breeders promoting efficient tick control with minimum acaricide use. Boosted regression tree analysis showed a significant (p = 0.002) reduction of ≈33% in the number of acaricide treatments from 7.9 to 5.3 per year by using PCM. Of the 24 factors identified as potentially affecting acaricide use, six factors accounted for ≈86% of the variability in number of acaricide treatments applied annually. The six most influential factors involved farm characteristics as well as pasture and herd management recommendations. These results demonstrated the usefulness of PCM for integrated control of R. australis infestations while reducing acaricide use to improve cattle production in New Caledonia.
Assuntos
Acaricidas , Doenças dos Bovinos , Rhipicephalus , Controle de Ácaros e Carrapatos , Infestações por Carrapato , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Nova Caledônia , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterináriaRESUMO
System-of-systems approaches for integrated assessments have become prevalent in recent years. Such approaches integrate a variety of models from different disciplines and modeling paradigms to represent a socio-environmental (or social-ecological) system aiming to holistically inform policy and decision-making processes. Central to the system-of-systems approaches is the representation of systems in a multi-tier framework with nested scales. Current modeling paradigms, however, have disciplinary-specific lineage, leading to inconsistencies in the conceptualization and integration of socio-environmental systems. In this paper, a multidisciplinary team of researchers, from engineering, natural and social sciences, have come together to detail socio-technical practices and challenges that arise in the consideration of scale throughout the socio-environmental modeling process. We identify key paths forward, focused on explicit consideration of scale and uncertainty, strengthening interdisciplinary communication, and improvement of the documentation process. We call for a grand vision (and commensurate funding) for holistic system-of-systems research that engages researchers, stakeholders, and policy makers in a multi-tiered process for the co-creation of knowledge and solutions to major socio-environmental problems.
RESUMO
Charcot neuroarthropathy is a degenerative disorder that significantly impairs a patient's functional capacity. It has been reported that a Charcot patient's quality of life is significantly impacted by the disease state. The aim of this study is to compare measured energy expenditure to a patient's perceived quality of life and physical ability. The study enrolled 43 patients by set inclusion and exclusion criteria. Patients' total energy expenditure was measured with doubly labeled water. The patients also completed 2 quality of life assessments: 36-Item Short Form Survey (SF-36) and International Physical Activity Questionnaire-Long Form (IPAQ-LF). The measured energy expenditure was then compared to the patient's perceived functional capacity. Scores reaching statistical significance included general health (60 ± 21; pâ¯=â¯.011), pain (62 ± 27; pâ¯=â¯.025), emotional (61 ± 40; p < .017), physical limitation (45 ± 39; p < .0001), and physical function (50 ± 29; p < .001). SF-36 survey variables that did not reach statistical significance included mental (73 ± 26; pâ¯=â¯.690), energy (55 ± 21; pâ¯=â¯.205), and social (74 ± 26; pâ¯=â¯.105). The IPAQ-LF and physical activity level (PAL) were compared. No identified variation was noted between the 2 test methods (pâ¯=â¯.57). The patients' PAL was measured at 1.4 ± 0.42, which is comparable to the general population. Data from this study identify the Charcot population as comparable to the general population. The inferences taken from this study indicate that this population suffers from poor health outlooks compared with the general population but may be overestimating the level of perceived disability.
Assuntos
Esclerose Lateral Amiotrófica , Exercício Físico , Qualidade de Vida , Esclerose Lateral Amiotrófica/fisiopatologia , Humanos , Inquéritos e QuestionáriosRESUMO
The tick Rhipicephalus australis, formerly known as Rhipicephalus microplus, is the most economically important ectoparasite of livestock in New Caledonia, affecting cattle health and production. Decades of control attempts based on the application of chemical acaricides have exerted a strong selective pressure on R. australis populations, some of which have evolved resistance to these treatments. Research to develop integrated tick control programs is now focused on decreasing applications of chemicals. This study reports the implementation of a method of pasture and herd management involving minimal strategic use of long-acting acaricides, here defined as those having substantial efficacy against larvae for several weeks. Diverse parameters concerning the utilization of long-acting acaricides in association with pasture and herd management on 21 New Caledonian farms over a 5-year period were analyzed to optimize their strategic use. Longer larval acaricidal effect was achieved with a commercial pour-on formulation of fluazuron than with a commercial injectable (subcutaneous) formulation containing 3.15% ivermectin. Pasture and herd management allowed an increase in the delay between a long-lasting acaricide application and the subsequent acaricide treatment from 11.0 weeks to 17.7 weeks. However, if ticks were detected and reported by producers on the day of a long-acting acaricide application, the delay to the following treatment was reduced from 18.5 weeks to 11.2 weeks. The impact of a long-acting acaricide treatment on larval populations in pastures was greatest with a stocking rate of 5 animals per hectare grazing during 1 week. These results provide science-based evidence to cattle producers for adaptive integrated tick management in order to delay the development of acaricide resistance.
Assuntos
Acaricidas , Doenças dos Bovinos , Rhipicephalus , Infestações por Carrapato , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Nova Caledônia , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterináriaRESUMO
Rangelands cover one third of the earth's land area, provide livelihoods for one billion persons, and most have been degraded by overgrazing of domestic livestock. Recent debate about best management practices often has centered on comparison of continuous grazing and rotational grazing. Resolution to this debate may lie in viewing rangelands as complex adaptive systems. We describe a spatially-structured, individual-based model of rangelands that embodies this perspective, and simulate forage dynamics and cattle production under semi-arid rangeland conditions typical of the southern Great Plains of the USA employing both continuous and rotational grazing. Relative "success" of simulated grazing schemes depended primarily on the evaluation metric used (e.g., rangeland ecological condition, sale weight of cattle, secondary production efficiency) and the particular manage scheme employed, and neither continuous nor rotational grazing schemes were uniformly more successful. Our results demonstrate that solution of the grazing systems debate is unlikely to be found in a single group of grazing schemes, but, rather, in adaptive management of feedbacks among system components. The present work provides an example of how modeling rangelands as complex adaptive systems can aid in the evaluation of management schemes.
Assuntos
Gado , Animais , BovinosRESUMO
Mechanisms underlying the loss of ecological resilience and a shift to an alternate regime with lower ecosystem service provisioning continues to be a leading debate in ecology, particularly in cases where evidence points to human actions and decision-making as the primary drivers of resilience loss and regime change. In this paper, we introduce the concept of coerced resilience as a way to explore the interplay among social power, ecological resilience, and fire management, and to better understand the unintended and undesired regime changes that often surprise ecosystem managers and governing officials. Philosophically, coercion is the opposite of freedom, and uses influence or force to gain compliance among local actors. The coercive force imposed by societal laws and policies can either enhance or reduce the potential to manage for essential structures and functions of ecological systems and, therefore, can greatly alter resilience. Using a classical fire-dependent regime shift from North America (tallgrass prairie to juniper woodland), and given that coercion is widespread in fire management today, we quantify relative differences in resilience that emerge in a policy-coerced fire system compared to a theoretical, policy-free fire system. Social coercion caused large departures in the fire conditions associated with alternative grassland and juniper woodland states, and the potential for a grassland state to emerge to dominance became increasingly untenable with fire as juniper cover increased. In contrast, both a treeless, grassland regime and a co-dominated grass-tree regime emerged across a wide range of fire conditions in the absence of policy controls. The severe coercive forcing present in fire management in the Great Plains, and corresponding erosion of grassland resilience, points to the need for transformative environmental governance and the rethinking of social power structures in modern fire policies.
Assuntos
Ecossistema , Incêndios , Ecologia , Florestas , Humanos , América do NorteAssuntos
Cálcio , Neoplasias , Feminino , Humanos , Seguimentos , Causas de Morte , Incidência , Vitamina D , Cálcio da Dieta , Saúde da Mulher , Neoplasias/epidemiologia , Suplementos NutricionaisRESUMO
OBJECTIVE: Computerized tomography (CT) is often employed to diagnose or rule out certain suspected abdominal pathologies. The aim of this study is to compare emergency physicians' estimated post-test disease probabilities to the probabilities obtained for similar diagnostic tests as reported in the literature. METHODS: Physicians were asked to estimate pre and posttest probabilities before and after CT scan results in patients with nontraumatic abdominal and pelvic pain. The actual post-test probability was calculated using published likelihood ratios and compared to physician judgment. RESULTS: 210 patient encounters were included. In the negative CT group, physicians' median pre-test probability was 40% with a post-test probability of 0%, while the actual post-test probability is 4.2% (p<0.001). Physicians' median pre-test probability for a positive CT was 70% with a post-test probability of 100%, while the actual post-test probability is 98% (p<0.001). The diverticulitis subgroup had no significant differences between physician and actual post-test probabilities. The post-op abscess subgroup had significant differences in post-test probabilities in both the negative CT (30% difference, p=0.028) and positive CT subgroups (-37% difference, p=0.003). CONCLUSIONS: When applying the probability theory of disease, physicians tend to overestimate the power of CT scanning. The difference in physician and actual post-test probabilities may be small or not clinically significant in diseases with good positive and negative likelihood ratios such as in diverticulitis; however, this difference may be large and clinically significant in diseases with poor likelihood ratios such as in post-op abscess.
Assuntos
Dor Abdominal/diagnóstico por imagem , Compreensão , Médicos/psicologia , Tomografia Computadorizada por Raios X , Dor Abdominal/etiologia , Dor Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Centros de Atenção Terciária , Adulto JovemAssuntos
Doenças Cardiovasculares , Ácidos Graxos Ômega-3 , Neoplasias , Ácidos Graxos , Humanos , Prevenção Primária , Vitamina DRESUMO
Global cancer incidence and mortality rates are high and increasing. Thus, it is imperative to find novel solutions to preventing cancer incidence and treating it at an affordable yet efficacious manner. The solar UVB-vitamin D-cancer hypothesis was first proposed in 1980 based on a geographical ecological study. Since then, numerous ecological and observational studies as well as studies of mechanisms have provided support for the hypothesis. However, observational studies have not provided consistent support, in part due to using a single blood draw from any season to use for serum 25-hydroxyvitamin D [25(OH)D] concentration in prospective studies with long follow-up times. Case-controls studies, in which blood is drawn near time of diagnosis, and prospective studies in which blood is drawn in the sunnier half of the year, are more likely to find significant inverse relations between 25(OH)D and cancer incidence. Three vitamin D plus calcium clinical trials have found significant reduction in all-cancer incidence. This paper reviews the evidence for vitamin D in reducing incidence of and increasing survival from breast, colorectal, lung, ovarian, pancreatic, and prostate cancer. The epidemiological evidence provides strong support for all of these types of cancer except for non-aggressive prostate cancer. Studies of the cellular mechanisms of vitamin D action in different cancer cell types, strongly indicate that vitamin D can exert protective and anti-tumorigenic activities that would retard cellular transformation, hyperplasia and cancer progression. Based on the scientific evidence reviewed in this paper, individuals and health providers can consider increasing 25(OH)D concentrations through sensible sun exposure and/or vitamin D supplementation to reduce risk of and, in conjunction with standard care, treat cancer. Public health acceptance of vitamin D for cancer prevention and treatment requires stronger support from vitamin D clinical trials.
Assuntos
Ensaios Clínicos como Assunto , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/prevenção & controle , Raios Ultravioleta , Vitamina D/fisiologia , Ensaios Clínicos como Assunto/métodos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Humanos , Incidência , Masculino , Neoplasias/mortalidade , Fatores de Risco , Luz SolarRESUMO
Increasing evidence suggests that vitamin D exerts multiple effects beyond bone and calcium metabolism. Vitamin D seems to play a role in pancreatic disease, including type 1 and type 2 diabetes mellitus as well as pancreatic cancer. Vitamin D's immune-modulatory action suggests that it could help prevent type 1 diabetes. In type 2 diabetes, vitamin D may influence ß-cell function, insulin sensitivity, and systematic inflammation-all characteristic pathways of that disease. Data from observational studies correlated vitamin D deficiency with risk of type 1 and type 2 diabetes. Prospective and ecological studies of pancreatic cancer incidence generally support a beneficial effect of higher 25-hydroxyvitamin D concentration as well as inverse correlations between UVB dose or exposure and incidence and/or mortality rate of pancreatic cancer. This review discusses the literature regarding vitamin D's role in risk of diabetes and pancreatic cancer. The results to date generally satisfy Hill's criteria for causality regarding vitamin D and incidence of these pancreatic diseases. However, large randomized, blinded, prospective studies are required to more fully evaluate the potential therapeutic role of vitamin D in preventing pancreatic diseases.
Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Neoplasias Pancreáticas/epidemiologia , Luz Solar , Vitamina D/biossíntese , Vitamina D/uso terapêutico , Diabetes Mellitus Tipo 2/prevenção & controle , Humanos , Neoplasias Pancreáticas/prevenção & controle , Estudos Prospectivos , Deficiência de Vitamina D , VitaminasRESUMO
BACKGROUND: Anatomy is a subject essential to medical practice, yet time committed to teaching is on the decline, and resources required to teach anatomy is costly, particularly dissection. Advances in technology are a potential solution to the problem, while maintaining the quality of teaching required for eventual clinical application. AIM: To identify methods used to teach anatomy, including those demonstrated to enhance knowledge acquisition and retention. METHODS: PubMed, CINAHL, ERIC, Academic OneFile, ProQuest, SAGE journals and Scopus were search from the earliest entry of each database to 31 August 2015. All included articles were assessed for methodological quality and low quality articles were excluded from the study. Studies were evaluated by assessment scores, qualitative outcomes where included as well as a modified Kirkpatrick model. RESULTS: A total of 17,820 articles were initially identified, with 29 included in the review. The review found a wide variety of teaching interventions represented in the range of studies, with CAI/CAL studies predominating in terms of teaching interventions, followed by simulation. In addition to this, CAI/CAL and simulation studies demonstrated better results overall compared to traditional teaching methods and there is evidence to support CAI/CAL as a partial replacement for dissection or a valuable tool in conjunction with dissection. CONCLUSIONS: This review provides evidence in support of the use of alternatives to traditional teaching methods in anatomy, in particular, the use of CAI/CAL with a number of high quality, low risk of bias studies supporting this.
Assuntos
Anatomia/educação , Aprendizagem , Ensino , Competência Clínica , HumanosRESUMO
UNLABELLED: Rates of Alzheimer's disease (AD) are rising worldwide. The most important risk factors seem to be linked to diet. For example, when Japan made the nutrition transition from the traditional Japanese diet to the Western diet, AD rates rose from 1% in 1985 to 7% in 2008. Foods protective against AD include fruits, vegetables, grains, low-fat dairy products, legumes, and fish, whereas risk factors include meat, sweets, and high-fat dairy products. The evidence comes from ecological and observational studies as well as investigations of the mechanisms whereby dietary factors affect risk. The mechanisms linking dietary risk factors to AD are fairly well known and include increased oxidative stress from metal ions such as copper as well as from advanced glycation end products associated with high-temperature cooking, increased homocysteine concentrations, and cholesterol and its effects on amyloid beta, insulin resistance, and obesity. Lower 25-hydroxyvitamin D concentrations also are associated with increased risk of AD. In addition to reviewing the journal literature, a new ecological study was conducted using AD prevalence from 10 countries (Brazil, Chile, Cuba, Egypt, India, Mongolia, Nigeria, Republic of Korea, Sri Lanka, and the United States) along with dietary supply data 5, 10, and 15 years before the prevalence data. Dietary supply of meat or animal products less milk 5 years before AD prevalence had the highest correlations with AD prevalence in this study. Thus, reducing meat consumption could significantly reduce the risk of AD as well as of several cancers, diabetes mellitus type 2, stroke, and, likely, chronic kidney disease. TEACHING POINTS: ⢠Single-country ecological data can be used to find links between diet and AD because the national diet changes, such as during the nutrition transition to a Western diet. ⢠Multicountry ecological studies can be used to find links between dietary factors and risk of AD. ⢠Prospective observational studies are useful in linking dietary components and patterns to risk of AD. ⢠The most important dietary link to AD appears to be meat consumption, with eggs and high-fat dairy also contributing. ⢠Diets high in grains, fruits, vegetables, and fish are associated with reduced risk of AD, but these factors cannot counter the effects of meat, eggs, and high-fat dairy. ⢠Higher vitamin D status is associated with reduced risk of AD.