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1.
Global Health ; 17(1): 119, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627303

RESUMO

The major threat to human societies posed by undernutrition has been recognised for millennia. Despite substantial economic development and scientific innovation, however, progress in addressing this global challenge has been inadequate. Paradoxically, the last half-century also saw the rapid emergence of obesity, first in high-income countries but now also in low- and middle-income countries. Traditionally, these problems were approached separately, but there is increasing recognition that they have common drivers and need integrated responses. The new nutrition reality comprises a global 'double burden' of malnutrition, where the challenges of food insecurity, nutritional deficiencies and undernutrition coexist and interact with obesity, sedentary behaviour, unhealthy diets and environments that foster unhealthy behaviour. Beyond immediate efforts to prevent and treat malnutrition, what must change in order to reduce the future burden? Here, we present a conceptual framework that focuses on the deeper structural drivers of malnutrition embedded in society, and their interaction with biological mechanisms of appetite regulation and physiological homeostasis. Building on a review of malnutrition in past societies, our framework brings to the fore the power dynamics that characterise contemporary human food systems at many levels. We focus on the concept of agency, the ability of individuals or organisations to pursue their goals. In globalized food systems, the agency of individuals is directly confronted by the agency of several other types of actor, including corporations, governments and supranational institutions. The intakes of energy and nutrients by individuals are powerfully shaped by this 'competition of agency', and we therefore argue that the greatest opportunities to reduce malnutrition lie in rebalancing agency across the competing actors. The effect of the COVID-19 pandemic on food systems and individuals illustrates our conceptual framework. Efforts to improve agency must both drive and respond to complementary efforts to promote and maintain equitable societies and planetary health.


Assuntos
Previsões , Saúde Global/tendências , Desnutrição/epidemiologia , Desnutrição/prevenção & controle , Humanos
2.
Am J Clin Nutr ; 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591100

RESUMO

BACKGROUND: Maternal nutrition is associated with epigenetic and cardiometabolic risk factors in offspring. Research in humans has primarily focused on assessing the impact of individual nutrients. OBJECTIVE: We sought to assess the collective impact of maternal dietary monounsaturated (MUFA), polyunsaturated (PUFA), and saturated fat (SFA) on epigenetic aging and cardiometabolic risk markers in healthy newborn infants using a geometric framework approach. DESIGN: Body fatness (n = 162), aortic intima-media thickness (n = 131), heart rate variability (n = 118), and epigenetic age acceleration (n = 124) were assessed in newborn infants. Maternal dietary intake was cross-sectionally assessed in the immediate postpartum period via a validated 80-item self-administered food-frequency questionnaire. Generalized additive models were used to explore interactive associations of nutrient intake, with results visualized as response surfaces. RESULTS: After adjustment for total energy intake, maternal age, gestational age, and sex there was a 3-way interactive association of MUFA, PUFA, and SFA (P = 0.001) with newborn epigenetic aging. This suggests that the nature of each fat class association depends upon one another. Response surfaces revealed MUFA was positively associated with newborn epigenetic age acceleration only at proportionately lower intakes of SFA or PUFA. We also demonstrate a potential beneficial association of omega-3 PUFA with newborn epigenetic age acceleration (P = 0.008). There was no significant association of fat class with newborn aortic intima-media thickness, heart rate variability, or body fatness. CONCLUSIONS: In this study, we demonstrate an association between maternal dietary fat class composition and epigenetic aging in newborns. Future research should consider other characteristics such as the source of maternal dietary fatty acids.

3.
J Agric Food Chem ; 69(40): 11890-11899, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34586803

RESUMO

Naringin, a natural flavonoid mainly found in citrus fruit, has been reported to exert a positive effect on improving skeletal muscle health. However, the effects and potential mechanisms of naringin on skeletal muscle fiber switching is still unclear. Here, we discovered that oral administration of naringin increased the low-speed running time, four-limb hanging time, body oxygen consumption in mice, enhanced aerobic enzyme activity, MyHC I expression, and slow-twitch fiber percentage in mice skeletal muscle. By contrast, naringin decreased α-GPDH enzyme activity, MyHC IIb expression, and fast-twitch fiber percentage. Moreover, naringin increased the concentration of serum adiponectin and activated the expression of AdipoR1, APPL1, AMPK, and PGC-1α. Furthermore, by the in vitro experiment and AdipoR1 knockdown, we found that inhibition of the AdipoR1 signaling pathway significantly reduced the effect of naringin on slow-twitch fiber-/fast-twitch fiber-related gene and protein expression. In conclusion, our results indicated that naringin could induce skeletal muscle fiber transition from fast twitch to slow twitch via the AdipoR1 signaling pathway. This study may provide new strategy for improving exercise endurance and slow muscle fiber deficiency-related diseases.

4.
Nutrients ; 13(7)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371932

RESUMO

BACKGROUND: There are numerous guidelines developed for bone health. Yet, it is unclear whether the differences in guideline development methods explain the variability in the recommendations for vitamin D and calcium intake. The objective of this systematic review was to collate and compare recommendations for vitamin D and calcium across bone health guidelines, assess the methods used to form the recommendations, and explore which methodological factors were associated with these guideline recommendations. METHODS: We searched MEDLINE, EMBASE, CINAHL, and other databases indexing guidelines to identify records in English between 2009 and 2019. Guidelines or policy statements on bone health or osteoporosis prevention for generally healthy adults aged ≥40 years were eligible for inclusion. Two reviewers independently extracted recommendations on daily vitamin D and calcium intake, supplement use, serum 25 hydroxyvitamin D [25(OH)D] level, and sunlight exposure; assessed guideline development methods against 25 recommended criteria in the World Health Organization (WHO) handbook for guideline development; and, identified types identified types of evidence underpinning the recommendations. RESULTS: we included 47 eligible guidelines from 733 records: 74% of the guidelines provided vitamin D (200~600-4000 IU/day) and 70% provided calcium (600-1200 mg/day) recommendations, 96% and 88% recommended vitamin D and calcium supplements, respectively, and 70% recommended a specific 25(OH)D concentration. On average, each guideline met 10 (95% CI: 9-12) of the total of 25 methodological criteria for guideline development recommended by the WHO Handbook. There was uncertainty in the association between the methodological criteria and the proportion of guidelines that provided recommendations on daily vitamin D or calcium. Various types of evidence, including previous bone guidelines, nutrient reference reports, systematic reviews, observational studies, and perspectives/editorials were used to underpin the recommendations. CONCLUSIONS: There is considerable variability in vitamin D and calcium recommendations and in guideline development methods in bone health guidelines. Effort is required to strengthen the methodological rigor of guideline development and utilize the best available evidence to underpin nutrition recommendations in evidence-based guidelines on bone health.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Cálcio/administração & dosagem , Suplementos Nutricionais , Guias de Prática Clínica como Assunto/normas , Recomendações Nutricionais , Vitamina D/administração & dosagem , Adulto , Osso e Ossos/fisiopatologia , Cálcio/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Medicina Baseada em Evidências/normas , Feminino , Nível de Saúde , Disparidades em Assistência à Saúde/normas , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Osteoporose/prevenção & controle , Vitamina D/efeitos adversos
5.
Adv Nutr ; 12(5): 1751-1767, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34117485

RESUMO

While sodium and potassium are individually important for blood pressure (BP) regulation, the relative contribution of sodium to potassium intake has not been sufficiently investigated. This study aimed to evaluate the association between urinary sodium to potassium ratio (UNa: K) and systolic and diastolic BP in adults. A systematic review (PROSPERO; CRD42016035296) was conducted and was reported according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Three scientific databases (MEDLINE, Scopus, Web of Science) were searched to March 2020 while reference lists of included articles were further hand-searched. Randomized controlled trials (RCT), cohort and cross-sectional studies that assessed 24-h urinary excretion in adults were included. Data from eligible studies were extracted and summarized. Random effects meta-analysis was conducted on RCT data to assess standardized mean differences (SMD) in systolic and diastolic BP according to 24-h UNa: K. Thirty-nine studies were included. Meta-analysis of 5 RCTs found a lower UNa: K ratio to be associated with a significantly greater reduction in systolic and diastolic BP compared with a higher UNa: K ratio [SMD: -1.09 (95% CI: -1.91, -0.28) mmHg and -1.42 (95% CI: -2.24, -0.59) mmHg, respectively]. Heterogeneity between RCTs was observed in systolic and diastolic BP (I2 = 97%, P < 0.0001 and I2 = 98%, P < 0.0001, respectively). The current body of evidence demonstrates that a lower 24-h UNa: K ratio is associated with lower BP in adults. Dietary strategies to achieve an increase in potassium while at the same time lowering sodium would be beneficial in lowering BP.


Assuntos
Hipertensão , Potássio , Adulto , Pressão Sanguínea , Dieta , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sódio
6.
Nutrients ; 13(5)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069005

RESUMO

The food environment in New Caledonia is undergoing a transition, with movement away from traditional diets towards processed and discretionary foods and beverages. This study aimed to develop an up-to-date food composition database that could be used to analyze food and nutritional intake data of New Caledonian children and adults. Development of this database occurred in three phases: Phase 1, updating and expanding the number of food items to represent current food supply; Phase 2, refining the database items and naming and assigning portion size images for food items; Phase 3, ensuring comprehensive nutrient values for all foods, including saturated fat and total sugar. The final New Caledonian database comprised a total of 972 food items, with 40 associated food categories and 25 nutrient values and 615 items with portion size images. To improve the searchability of the database, the names of 593 food items were shortened and synonyms or alternate spelling were included for 462 foods. Once integrated into a mobile app-based multiple-pass 24-h recall tool, named iRecall.24, this country-specific food composition database would support the assessment of food and nutritional intakes of families in New Caledonia, in a cross-sectional and longitudinal manner, and with translational opportunities for use across the wider Pacific region.


Assuntos
Gerenciamento de Dados , Bases de Dados Factuais , Ingestão de Alimentos , Aplicativos Móveis , Avaliação Nutricional , Adulto , Bebidas , Criança , Estudos Transversais , Dieta , Carboidratos da Dieta , Eletrônica , Ingestão de Energia , Abastecimento de Alimentos , Humanos , Melanesia , Nova Caledônia , Nutrientes , Polinésia , Tamanho da Porção
7.
Nat Metab ; 3(6): 810-828, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34099926

RESUMO

Reduced protein intake, through dilution with carbohydrate, extends lifespan and improves mid-life metabolic health in animal models. However, with transition to industrialised food systems, reduced dietary protein is associated with poor health outcomes in humans. Here we systematically interrogate the impact of carbohydrate quality in diets with varying carbohydrate and protein content. Studying 700 male mice on 33 isocaloric diets, we find that the type of carbohydrate and its digestibility profoundly shape the behavioural and physiological responses to protein dilution, modulate nutrient processing in the liver and alter the gut microbiota. Low (10%)-protein, high (70%)-carbohydrate diets promote the healthiest metabolic outcomes when carbohydrate comprises resistant starch (RS), yet the worst outcomes were with a 50:50 mixture of monosaccharides fructose and glucose. Our findings could explain the disparity between healthy, high-carbohydrate diets and the obesogenic impact of protein dilution by glucose-fructose mixtures associated with highly processed diets.


Assuntos
Dieta , Carboidratos da Dieta/metabolismo , Proteínas na Dieta/metabolismo , Metabolismo Energético , Homeostase , Animais , Glucose/metabolismo , Nível de Saúde , Masculino , Camundongos , Obesidade/etiologia , Obesidade/metabolismo , Amido/metabolismo
8.
Am J Primatol ; 83(7): e23269, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34002861

RESUMO

Primate foraging is influenced by the spatial and temporal distribution of foods, which may facilitate or constrain optimal nutrient intakes. Chimpanzees are frugivorous primates that mainly subsist on ripe fruit that is typically low in available protein (AP) and high in easily digestible carbohydrates. Because chimpanzees prefer ripe fruit and often eat it in large quantities compared with other foods, we hypothesized that protein intake would be tightly regulated while non-protein energy (NPE) would vary with fruit intake. To test this hypothesis, we conducted all-day follows on female chimpanzees, recorded all types of food consumed (i.e., drupes, figs, and non-fruit foods), estimated the nutritional contributions of these foods to daily NPE and AP intake and investigated how the ratio of NPE to AP varied due to changes in the types of foods consumed. Although the proportions of drupes, figs, and non-fruit foods varied in their diets, female chimpanzees maintained a relatively stable intake of AP while intake of NPE varied depending on the daily diet, demonstrating that like other frugivorous primates studied to date, chimpanzees prioritize protein. The mean daily ratio of NPE to AP was 7:1, which is similar to that of other frugivorous primates studied. Our results support the hypothesis that frugivorous animals may generally prioritize AP, while maximizing NPE intake within that constraint, and could shed light on aspects of human dietary evolution.

9.
Nutrients ; 13(4)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924065

RESUMO

Increased consumption of unhealthy processed foods, particularly those high in sodium, is a major risk factor for cardiovascular diseases. Nutrition information on packaged foods can help guide consumers toward products with less sodium, however the availability of nutrition information on foods sold in Kenya is currently unknown. The aims of this study were to estimate the proportion of packaged foods and beverages displaying nutrition information for sodium and determine the amount of sodium in packaged foods available for sale in Kenya. Data was collected in 2019 from five retail supermarkets in Nairobi. The availability of sodium information provided on packaged products and the sodium content were recorded. As secondary analyses, we compared sodium content labelling of products in Kenya by manufacturing location and the sodium content of products available in Kenya and South Africa. A total of 6003 packaged products in 56 food categories were identified. Overall, 39% of products displayed sodium content, though the availability of labelling varied widely between food categories, with coverage in main categories ranging from 0% (yoghurts and yoghurt drinks) to 86% (breakfast cereals). Food categories with the highest median sodium content were herbs and spices (9120 mg/100 g), sauces (1200 mg/100 g) and meat alternatives (766 mg/100 g) although wide variabilities were often observed within categories. Imported products were more likely to provide information on sodium than locally produced products (81% compared to 26%) and reported higher median sodium levels (172 mg/100 g compared to 96 mg/100 g). Kenyan products reported a higher median sodium content than South African products in six categories while South African products had higher median sodium in 20 categories, with considerable variation in median sodium content between countries in some categories. These findings highlight considerable potential to improve the availability of sodium information on packaged products in Kenya and to introduce reformulation policies to reduce the amount of sodium in the Kenyan food supply.


Assuntos
Bebidas/análise , Rotulagem de Alimentos , Embalagem de Alimentos , Sódio/análise , Bases de Dados como Assunto , Quênia , África do Sul , Supermercados
10.
Front Endocrinol (Lausanne) ; 12: 622292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776921

RESUMO

There is mounting evidence that obesity has negative repercussions for reproductive physiology in males. Much of this evidence has accumulated from rodent studies employing diets high in fat and sugar ("high fat" or "western" diets). While excessive fats and carbohydrates have long been considered major determinants of diet induced obesity, a growing body of research suggests that the relationships between diet composition and obesity are more complex than originally thought, involving interactions between dietary macronutrients. However, rodent dietary models have yet to evolve to capture this, instead relying heavily on elevated levels of a single macronutrient. While this approach has highlighted important effects of obesity on male reproduction, it does not allow for interpretation of the complex, interacting effects of dietary protein, carbohydrate and fat. Further, the single nutrient approach limits the ability to draw conclusions about which diets best support reproductive function. Nutritional Geometry offers an alternative approach, assessing outcomes of interest over an extended range of dietary macronutrient compositions. This review explores the practical application of Nutritional Geometry to study the effects of dietary macronutrient balance on male reproduction, including experimental considerations specific to studies of diet and reproductive physiology. Finally, this review discusses the promising use of Nutritional Geometry in the development of evidence-based pre-conception nutritional guidance for men.

11.
Proc Biol Sci ; 288(1942): 20202329, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33434459

RESUMO

Animal studies have shown that maternal resource allocation can be sex-biased in order to maximize reproductive success, yet this basic concept has not been investigated in humans. In this study, we explored relationships between maternal factors, offspring sex and prenatal and postnatal weight gain. Sex-specific regression models not only indicated that maternal ethnicity impacted male (n = 2456) and female (n = 1871) childrens postnatal weight gain differently but also that parity and mode of feeding influenced weight velocity of female (ß ± s.e. = -0.31 ± 0.11 kg, p = 0.005; ß ± s.e. = -0.37 ± 0.11 kg, p < 0.001) but not male offspring. Collectively, our findings imply that maternal resource allocation to consecutive offspring increases after a male firstborn. The absence of this finding in formula fed children suggests that this observation could be mediated by breast milk. Our results warrant further mechanistic and epidemiological studies to elucidate the role of breastfeeding on the programming of infant growth as well as of metabolic and cardiovascular diseases, with potential implications for tailoring infant formulae according to sex and birth order.


Assuntos
Aleitamento Materno , Irmãos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Leite Humano , Gravidez , Ganho de Peso
12.
Cardiovasc Res ; 117(2): 386-401, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-32386289

RESUMO

Carbohydrates are the major source of dietary energy, but their role in health and disease remains controversial. Recent epidemiological evidence suggests that the increased consumption of carbohydrates is associated with obesity and increased risk of mortality and dietary trials show that carbohydrate restriction leads to weight loss and improved glycaemic status in obese and diabetic subjects. In contrast, the diets of populations with long and healthy lifespans (e.g. traditional Okinawans from Japan) are high in carbohydrate and low in protein, and several clinical and preclinical studies have linked low-carbohydrate-high-protein diets with increased mortality risk. In this paper we attempt to reconcile these contradictory findings by moving beyond traditional single-nutrient analyses to consider the interactions between nutrients on health outcomes. We do so using the Geometric Framework (GF), a nutritional modelling platform that explicitly considers the main and interactive effects of multiple nutrients on phenotypic characteristics. Analysis of human data by GF shows that weight loss and improved cardio-metabolic outcomes under carbohydrate restriction derive at least in part from reduced caloric intake due to the concomitantly increased proportion of protein in the diet. This is because, as in many animals, a specific appetite for protein is a major driver of food intake in humans. Conversely, dilution of protein in the diet leverages excess food intake through compensatory feeding for protein ('protein leverage'). When protein is diluted in the diet by readily digestible carbohydrates and fats, as is the case in modern ultra-processed foods, protein leverage results in excess calorie intake, leading to rising levels of obesity and metabolic disease. However, when protein is diluted in the diet by increased quantities of less readily digestible forms of carbohydrate and fibre, energy balance is maintained and health benefits accrue, especially during middle age and early late-life. We argue that other controversies in carbohydrate research can be resolved using the GF methodology in dietary studies.

13.
Public Health Nutr ; 24(14): 4614-4621, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33357250

RESUMO

OBJECTIVE: To assess the contribution of different food groups to total salt purchases and to evaluate the estimated reduction in salt purchases if mandatory maximum salt limits in South African legislation were being complied with. DESIGN: This study conducted a cross-sectional analysis of purchasing data from Discovery Vitality members. Data were linked to the South African FoodSwitch database to determine the salt content of each food product purchased. Food category and total annual salt purchases were determined by summing salt content (kg) per each unit purchased across a whole year. Reductions in annual salt purchases were estimated by applying legislated maximum limits to product salt content. SETTING: South Africa. PARTICIPANTS: The study utilised purchasing data from 344 161 households, members of Discovery Vitality, collected for a whole year between January and December 2018. RESULTS: Vitality members purchased R12·8 billion worth of food products in 2018, representing 9562 products from which 264 583 kg of salt was purchased. The main contributors to salt purchases were bread and bakery products (23·3 %); meat and meat products (19 %); dairy (12·2 %); sauces, dressings, spreads and dips (11·8 %); and convenience foods (8·7 %). The projected total quantity of salt that would be purchased after implementation of the salt legislation was 250 346 kg, a reduction of 5·4 % from 2018 levels. CONCLUSIONS: A projected reduction in salt purchases of 5·4 % from 2018 levels suggests that meeting the mandatory maximum salt limits in South Africa will make a meaningful contribution to reducing salt purchases.

14.
J Anim Ecol ; 90(3): 751-765, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33314075

RESUMO

Apposite conceptualization and measurement of resource variation is critical for understanding many issues in ecology, including ecological niches, persistence and distribution of populations, the structure of communities and population resilience to perturbations. We apply the nutritional geometry framework to conceptualize and quantify the responses of a temperate-living primate, the golden snub-nosed monkey Rhinopithecus roxellana to variation in resource quality and quantity and in nutrient requirements associated with seasonal environments. We present a geometric model distinguishing qualitative constraint, quantitative constraint and 'pseudo-constraint' whereby nutrient intakes resemble response to qualitative resource constraint but are in fact driven by variation in nutrient requirements. The model is applied to analyse nutrient intakes recorded in 164 full-day observations of monkeys from two populations, one wild and the other captive, across seasons. Additionally, we recorded the diet of a single animal over 32 consecutive days in the wild. Despite considerable differences in available resources, the captive and wild populations showed marked similarities in nutrient intakes, including indistinguishable amounts and ratios of ingested macronutrients during summer and autumn and strong year-round maintenance of protein compared to seasonally variable fat and carbohydrate intakes. These similarities suggest homeostatically regulated nutritional targets and provide reference points to identify factors driving population differences in macronutrient intake in winter and spring. Our framework enabled us to distinguish examples of quantitative, qualitative and 'pseudo-constraint'. We suggest that this approach can increase the resolution at which resource constraint is conceptualized and measured in ecological studies.


Assuntos
Colobinae , Presbytini , Animais , China , Dieta/veterinária , Estações do Ano
15.
Ageing Res Rev ; 64: 101198, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33132154

RESUMO

Branched chain amino acids (BCAA: leucine, valine, isoleucine) have key physiological roles in the regulation of protein synthesis, metabolism, food intake and aging. Many studies report apparently inconsistent conclusions about the relationships between blood levels of BCAAs or dietary manipulation of BCAAs with age-related changes in body composition, sarcopenia, obesity, insulin and glucose metabolism, and aging biology itself. These divergent results can be resolved by consideration of the role of BCAAs as signalling molecules and the bidirectional mechanistic relationship between BCAAs and some aging phenotypes. The effects of BCAAs are also influenced by the background nutritional composition such as macronutrient ratios and imbalance with other amino acids. Understanding the interaction between BCAAs and other components of the diet may provide new opportunities for influencing age-related outcomes through manipulation of dietary BCAAs together with titration of macronutrient ratios and other amino acids.


Assuntos
Aminoácidos de Cadeia Ramificada , Resistência à Insulina , Envelhecimento , Humanos , Insulina , Isoleucina
16.
BMC Bioinformatics ; 21(1): 530, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203358

RESUMO

BACKGROUND: Nutrigenomics aims at understanding the interaction between nutrition and gene information. Due to the complex interactions of nutrients and genes, their relationship exhibits non-linearity. One of the most effective and efficient methods to explore their relationship is the nutritional geometry framework which fits a response surface for the gene expression over two prespecified nutrition variables. However, when the number of nutrients involved is large, it is challenging to find combinations of informative nutrients with respect to a certain gene and to test whether the relationship is stronger than chance. Methods for identifying informative combinations are essential to understanding the relationship between nutrients and genes. RESULTS: We introduce Local Consistency Nutrition to Graphics (LC-N2G), a novel approach for ranking and identifying combinations of nutrients with gene expression. In LC-N2G, we first propose a model-free quantity called Local Consistency statistic to measure whether there is non-random relationship between combinations of nutrients and gene expression measurements based on (1) the similarity between samples in the nutrient space and (2) their difference in gene expression. Then combinations with small LC are selected and a permutation test is performed to evaluate their significance. Finally, the response surfaces are generated for the subset of significant relationships. Evaluation on simulated data and real data shows the LC-N2G can accurately find combinations that are correlated with gene expression. CONCLUSION: The LC-N2G is practically powerful for identifying the informative nutrition variables correlated with gene expression. Therefore, LC-N2G is important in the area of nutrigenomics for understanding the relationship between nutrition and gene expression information.


Assuntos
Algoritmos , Análise de Dados , Nutrigenômica , Fenômenos Fisiológicos da Nutrição Animal , Animais , Simulação por Computador , Regulação da Expressão Gênica , Camundongos , Dinâmica não Linear
17.
Proc Natl Acad Sci U S A ; 117(48): 30824-30835, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33199593

RESUMO

Animal experiments have demonstrated that energy intake and the balance of macronutrients determine life span and patterns of age-specific mortality (ASM). Similar effects have also been detected in epidemiological studies in humans. Using global supply data and 1,879 life tables from 103 countries, we test for these effects at a macrolevel: between the nutrient supplies of nations and their patterns of ASM. We find that macronutrient supplies are strong predictors of ASM even after correction for time and economic factors. Globally, signatures of undernutrition are evident in the effects of low supply on life expectancy at birth and high mortality across ages, even as recently as 2016. However, in wealthy countries, the effects of overnutrition are prominent, where high supplies particularly from fats and carbohydrates are predicted to lead to high levels of mortality. Energy supplied at around 3,500 kcal/cap/d minimized mortality across ages. However, we show that the macronutrient composition of energy supply that minimizes mortality varies with age. In early life, 40 to 45% energy from each of fat and carbohydrate and 16% from protein minimizes mortality. In later life, replacing fat with carbohydrates to around 65% of total energy and reducing protein to 11% is associated with the lowest level of mortality. These results, particularly those regarding fats, accord both with experimental data from animals and within-country epidemiological studies on the association between macronutrient intake and risk of age-related chronic diseases.


Assuntos
Longevidade , Nutrientes , Estado Nutricional , Fatores Etários , Algoritmos , Bases de Dados Factuais , Dieta , Suplementos Nutricionais , Ingestão de Energia , Feminino , Geografia , Saúde Global , Humanos , Masculino , Modelos Teóricos , Nutrientes/provisão & distribuição , Inquéritos Nutricionais , Vigilância em Saúde Pública , Fatores Socioeconômicos
18.
Nutrients ; 12(5)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455838

RESUMO

The majority of the epidemiological evidence over the past few decades has linked high intake of fats, especially saturated fats, to increased risk of diabetes and cardiovascular disease. However, findings of some recent studies (e.g., the PURE study) have contested this association. High saturated fat diets (HFD) have been widely used in rodent research to study the mechanism of insulin resistance and metabolic syndrome. Two separate but somewhat overlapping models-the diacylglycerol (DAG) model and the ceramide model-have emerged to explain the development of insulin resistance. Studies have shown that lipid deposition in tissues such as muscle and liver inhibit insulin signaling via the toxic molecules DAG and ceramide. DAGs activate protein kinase C that inhibit insulin-PI3K-Akt signaling by phosphorylating serine residues on insulin receptor substrate (IRS). Ceramides are sphingolipids with variable acyl group chain length and activate protein phosphatase 2A that dephosphorylates Akt to block insulin signaling. In adipose tissue, obesity leads to infiltration of macrophages that secrete pro-inflammatory cytokines that inhibit insulin signaling by phosphorylating serine residues of IRS proteins. For cardiovascular disease, studies in humans in the 1950s and 1960s linked high saturated fat intake with atherosclerosis and coronary artery disease. More recently, trials involving Mediterranean diet (e.g., PREDIMED study) have indicated that healthy monounsaturated fats are more effective in preventing cardiovascular mortality and coronary artery disease than are low-fat, low-cholesterol diets. Antioxidant and anti-inflammatory effects of Mediterranean diets are potential mediators of these benefits.


Assuntos
Doenças Cardiovasculares/metabolismo , Dieta Hiperlipídica/efeitos adversos , Tecido Adiposo/metabolismo , Animais , Doenças Cardiovasculares/etiologia , Ceramidas/metabolismo , Citocinas/metabolismo , Diabetes Mellitus/metabolismo , Dieta com Restrição de Gorduras , Diglicerídeos/metabolismo , Ácidos Graxos/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Síndrome Metabólica , Obesidade , Fosfatidilinositol 3-Quinases/metabolismo
19.
Am J Clin Nutr ; 112(1): 6-7, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32338722
20.
Obesity (Silver Spring) ; 28(4): 822-829, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32144892

RESUMO

OBJECTIVE: The aim of this study was to test the protein leverage hypothesis in a cohort of youth with obesity. METHODS: A retrospective study was conducted in a cohort of youth with obesity attending a tertiary weight management service. Validated food questionnaires revealed total energy intake (TEI) and percentage of energy intake from carbohydrates (%EC), fats (%EF), and proteins (%EP). Individuals with a Goldberg cutoff ≥ 1.2 of the ratio of reported TEI to basal metabolic rate from fat-free mass were included. A subgroup had accelerometer data. Statistics included modeling of percentage of energy from macronutrients and TEI, compositional data analysis to predict TEI from macronutrient ratios, and mixture models for sensitivity testing. RESULTS: A total of 137 of 203 participants were included (mean [SD] age 11.3 [2.7] years, 68 females, BMI z score 2.47 [0.27]). Mean TEI was 10,330 (2,728) kJ, mean %EC was 50.6% (6.1%), mean %EF was 31.6% (4.9%), and mean %EP was 18.4% (3.1%). The relationship between %EP and TEI followed a power function (L coefficient -0.48; P < 0.001). TEI was inversely associated with increasing %EP. In the subgroup with < 60 min/d of moderate to vigorous physical activity (n = 48), lower BMI z scores were associated with higher %EP and moderate %EC. CONCLUSIONS: In youth with obesity, protein dilution by either carbohydrates or fats increases TEI. Assessment of dietary protein may be useful to assist in reducing TEI and BMI in youth with obesity.


Assuntos
Proteínas na Dieta/efeitos adversos , Ingestão de Energia/fisiologia , Obesidade/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
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