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PURPOSE OF REVIEW: The aim of this study is to summarize anthropometric and advanced methods used to assess body composition in adults diagnosed with type 2 diabetes (T2D) or at risk for T2D that provide clinically relevant information about T2D disease-related complications or risk factors. RECENT FINDINGS: Anthropometry is commonly used in clinical settings; however, provides unreliable estimates of fat mass, fat-free mass, and body fat distribution for metabolic health assessments compared to advanced techniques such as bioelectrical impedance analysis (BIA), dual-energy x-ray absorptiometry (DXA), computerized tomography (CT), and magnetic resonance imaging (MRI). Few studies report the clinical use of anthropometric and advanced body composition methods that identify T2D disease-related complications or T2D risk factors. Anthropometry, BIA, DXA, CT, and MRI were used to estimate body adiposity and distribution, visceral and subcutaneous adipose tissue depots, and skeletal muscle mass. Review findings indicate that these methods were capable of identifying clinically relevant T2D disease-related complications such as sarcopenia and T2D risk factors such as obesity or regional adiposity. However, estimates were often sex and race/ethnicity specific warranting cross-validation of these methods in broader populations with T2D or risk for T2D prior to clinical implementation.
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Diabetes Mellitus Tipo 2 , Absorciometría de Fotón , Tejido Adiposo/diagnóstico por imagen , Adulto , Antropometría , Composición Corporal , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Impedancia Eléctrica , HumanosRESUMEN
OBJECTIVE: Osteoarthritis is the most prominent form of arthritis, affecting approximately 15% of the population in the United States. Knee osteoarthritis (KOA) has become one of the leading causes of disability in older adults. Besides knee replacement, there are no curative treatments for KOA, so persistent pain is commonly treated with opioids, acetaminophen, and nonsteroidal anti-inflammatory drugs. However, these drugs have many unpleasant side effects, so there is a need for alternative forms of pain management. We sought to test the efficacy of a dietary intervention to reduce KOA. DESIGN: A randomized controlled pilot study to test the efficacy of two dietary interventions. SUBJECTS: Adults 65-75 years of age with KOA. METHODS: Participants were asked to follow one of two dietary interventions (low-carbohydrate [LCD], low-fat [LFD]) or continue to eat as usual (control [CTRL]) over 12 weeks. Functional pain, self-reported pain, quality of life, and depression were assessed every three weeks. Serum from before and after the diet intervention was analyzed for oxidative stress. RESULTS: Over a period of 12 weeks, the LCD reduced pain intensity and unpleasantness in some functional pain tasks, as well as self-reported pain, compared with the LFD and CTRL. The LCD also significantly reduced oxidative stress and the adipokine leptin compared with the LFD and CTRL. Reduction in oxidative stress was related to reduced functional pain. CONCLUSIONS: We present evidence suggesting that oxidative stress may be related to functional pain, and lowering it through our LCD intervention could provide relief from pain and be an opioid alternative.
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Dieta Baja en Carbohidratos/métodos , Dieta con Restricción de Grasas/métodos , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/dietoterapia , Dolor/etiología , Anciano , Femenino , Humanos , Masculino , Estrés Oxidativo/fisiología , Manejo del Dolor/métodos , Proyectos Piloto , Resultado del TratamientoRESUMEN
STUDY QUESTION: Do the determinants of insulin sensitivity/resistance differ in women with and without polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Peri-muscular thigh adipose tissue is uniquely associated with insulin sensitivity/resistance in women with PCOS, whereas adiponectin and thigh subcutaneous adipose are the main correlates of insulin sensitivity/resistance in women without PCOS. WHAT IS KNOWN ALREADY: In subject populations without PCOS, insulin sensitivity/resistance is determined by body fat distribution and circulating concentrations of hormones and pro-inflammatory mediators. Specifically, visceral (intra-abdominal) adipose tissue mass is adversely associated with insulin sensitivity, whereas thigh subcutaneous adipose appears protective against metabolic disease. Adiponectin is an insulin-sensitizing hormone produced by healthy subcutaneous adipose that may mediate the protective effect of thigh subcutaneous adipose. Testosterone, which is elevated in PCOS, may have an adverse effect on insulin sensitivity/resistance. STUDY DESIGN, SIZE, DURATION: Cross-sectional study of 30 women with PCOS and 38 women without PCOS; data were collected between 2007 and 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were group-matched for obesity, as reflected in BMI (Mean ± SD; PCOS: 31.8 ± 6.0 kg/m2; without PCOS: 31.5 ± 5.0 kg/m2). The whole-body insulin sensitivity index (WBISI) was assessed using a mixed-meal tolerance test; Homeostasis Model Assessment-Insulin resistance (HOMA-IR) was determined from fasting insulin and glucose values. Adipose tissue distribution was determined by computed tomography (CT) scan. Partial correlation analysis, adjusting for total fat mass, was used to identify correlates of WBISI and HOMA-IR within each group of women from measures of body composition, body fat distribution, reproductive-endocrine hormones and adipokines/cytokines. Stepwise multiple linear regression analysis was used to identify the variables that best predicted WBISI and HOMA-IR. MAIN RESULTS AND THE ROLE OF CHANCE: Among women with PCOS, both WBISI and HOMA-IR were best predicted by peri-muscular adipose tissue cross-sectional area. Among women without PCOS, both WBISI and HOMA-IR were best predicted by adiponectin and thigh subcutaneous adipose tissue. LIMITATIONS, REASONS FOR CAUTION: Small sample size, group matching for BMI and age, and the use of surrogate measures of insulin sensitivity/resistance. WIDER IMPLICATIONS OF THE FINDINGS: Because insulin resistance is the root cause of obesity and comorbidities in PCOS, determining its cause could lead to potential therapies. Present results suggest that peri-muscular adipose tissue may play a unique role in determining insulin sensitivity/resistance in women with PCOS. Interventions such as restriction of dietary carbohydrates that have been shown to selectively reduce fatty infiltration of skeletal muscle may decrease the risk for type 2 diabetes in women with PCOS. STUDY FUNDING/COMPETING INTERESTS: The study was supported by National Institutes of Health grants R01HD054960, R01DK67538, P30DK56336, P60DK079626, M014RR00032 and UL1RR025777. The authors have no conflicts of interest. TRIAL REGISTRATION NUMBER: NCT00726908.
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Tejido Adiposo/metabolismo , Resistencia a la Insulina/fisiología , Músculo Esquelético/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adulto , Glucemia , Composición Corporal , Índice de Masa Corporal , Estudios Transversales , Estradiol/sangre , Femenino , Humanos , Insulina/sangre , Persona de Mediana Edad , Testosterona/sangre , Muslo , Adulto JovenRESUMEN
The objective of the study was to assess the agreement of the Lunar Prodigy with the newer Lunar iDXA dual-energy X-ray absorptiometer for determining total body and regional (arms, legs, trunk) bone mineral density (BMD), bone mineral content (BMC), fat mass (FM), lean tissue mass (LTM), total body mass, and percent fat. Ninety-two healthy adult males (n = 36) and females (n = 56) were scanned consecutively on the iDXA and the Prodigy dual-energy X-ray absorptiometers. For iDXA, relative to Prodigy, paired t tests indicated significantly lower estimates for total body and regional BMD and BMC (p < 0.001). Measures of total body and trunk FM, LTM, and percent fat did not differ between the instruments. In regional analyses, estimates of FM and percent fat were greater, and that of LTM was lower, in the arms (p < 0.001). In contrast, iDXA estimates of LTM were higher in the legs (p < 0.001). All body composition measures were significantly correlated (p < 0.001). Bland-Altman analyses indicated that significant bias existed between iDXA and Prodigy for total body and regional BMD estimates (p < 0.001) such that iDXA underestimated BMD to a greater extent in persons with higher values. In addition, iDXA overestimation bias existed for FM in total body, arms, and legs, and the overestimation was primarily observed in participants with greater body fat (p < 0.001). When combining or comparing data from iDXA with those from Prodigy, investigators should be aware that certain total body and regional estimates are significantly different. The greatest percent differences were observed for arm BMD, FM, and percent fat.
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Absorciometría de Fotón/instrumentación , Tejido Adiposo/diagnóstico por imagen , Composición Corporal , Densidad Ósea , Adulto , Anciano , Brazo/diagnóstico por imagen , Femenino , Voluntarios Sanos , Humanos , Pierna/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Torso/diagnóstico por imagen , Adulto JovenRESUMEN
The aim of this study is to test the hypothesis that a breakfast meal with high carbohydrate/low fat results in an earlier increase in postprandial glucose and insulin, a greater decrease below baseline in postprandial glucose, and an earlier return of appetite, compared with a low carbohydrate/high fat meal. Overweight but otherwise healthy adults (n = 64) were maintained on one of two eucaloric diets: high carbohydrate/low fat (HC/LF; 55:27:18% kcals from carbohydrate:fat:protein) versus low carbohydrate/high fat (LC/HF; 43:39:18% kcals from carbohydrate:fat:protein). After 4 weeks of acclimation to the diets, participants underwent a meal test during which circulating glucose and insulin and self-reported hunger and fullness, were measured before and after consumption of breakfast from their assigned diets. The LC/HF meal resulted in a later time at the highest and lowest recorded glucose, higher glucose concentrations at 3 and 4 hours post meal, and lower insulin incremental area under the curve. Participants consuming the LC/HF meal reported lower appetite 3 and 4 hours following the meal, a response that was associated with the timing of the highest and lowest recorded glucose. Modest increases in meal carbohydrate content at the expense of fat content may facilitate weight gain over the long-term by contributing to an earlier rise and fall of postprandial glucose concentrations and an earlier return of appetite.
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Glucemia/metabolismo , Desayuno , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Hambre/fisiología , Adulto , Apetito/fisiología , Dieta , Carbohidratos de la Dieta/análisis , Grasas de la Dieta/análisis , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Ácidos Grasos/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Voluntarios Sanos , Humanos , Insulina/sangre , Modelos Lineales , Masculino , Persona de Mediana Edad , Periodo Posprandial , Adulto JovenRESUMEN
Prediabetes affects 38% of U.S. adults and is primarily linked to added sugars consumed from sugar-sweetened beverages. It is unclear if total dietary intake of added sugar also increases the risk for prediabetes. This study examined if total (g/day) and percent intakes of <10%, 10-15%, or >15% added sugar increase the odds for prediabetes in U.S. adults. A cross-sectional, secondary analysis using 2013-2018 NHANES data was conducted. This study included data from U.S. adults ≥ 20 years with normoglycemia (N = 2,154) and prediabetes (N = 3,152) with 1-2 days of dietary recall information. Prediabetes was defined as a hemoglobin A1c of 5.7%-6.4% or a fasting plasma glucose of 100-125 mg/dL. Survey-weighted logistic regression was used to estimate odds ratios of prediabetes based on usual intakes of added sugar (total and percent intakes) using the National Cancer Institute Method. Differences in prediabetes risk and total and percent intakes of added sugar were compared by race/ethnicity. The sample's total energy intake from added sugar was 13.9%. Total (unadjusted: OR: 1.01, 95% CI: .99-1.00, p = .26; adjusted: OR: 1.00, 95% CI: .99-1.00, p = .91) and percent intakes of added sugar (unadjusted [<10%: (ref); 10-15%: OR: .93, 95% CI: .77-1.12, p = .44; >15%: OR: 1.03, 95% CI: .82-1.28, p = .82] and adjusted [<10%: (ref); 10-15%: OR: .82, 95% CI: .65-1.04, p = .09; >15%: OR: .96, 95% CI: .74-1.24, p = .73]) were not significantly associated with an increased odds of prediabetes. Prediabetes risk did not differ by race/ethnicity for total (unadjusted model [p = .65]; adjusted model [p = .51]) or percent (unadjusted model [p = .21]; adjusted model [p = .11]) added sugar intakes. In adults ≥20 years with normoglycemia and prediabetes, total added sugar consumption did not significantly increase one's risk for prediabetes and risk estimates did not differ by race/ethnicity. Experimental studies should expand upon this work to confirm these findings.
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Estado Prediabético , Adulto , Humanos , Encuestas Nutricionales , Estado Prediabético/epidemiología , Estado Prediabético/etiología , Estudios Transversales , Bebidas/análisis , Sacarosa en la DietaRESUMEN
AIMS: Adults aware of having prediabetes report engaging in dietary risk-reduction behavior changes. However, no studies have assessed if prediabetes awareness influences self-reported consumption of added sugar. METHODS: Cross-sectional data from 3314 adults, 20 years and older, with prediabetes were analyzed from 2013-2018 National Health and Nutrition Examination Survey data. Survey-weighted ordinary least squares regression was used to test whether prediabetes awareness was associated with usual intake of added sugar (g/day) using the National Cancer Institute Method by age, sex, and race/Hispanic origin after controlling for sociodemographic covariates. RESULTS: Among 3314 adults with prediabetes, 528 reported being aware and 2786 reported being unaware of their condition. Prediabetes awareness was not significantly associated with added sugar consumption (estimated difference 1.7 g; 95% CI: - .80, 4.20; P = .18). There were no significant differences in added sugar consumption among those aware of their condition for age, sex, or race/Hispanic origin (Type 3 test for age: P = .15, male: P = .86, race, and Hispanic origin: P = .89). CONCLUSION: Adults with prediabetes, aware of their condition, do not consume significantly lower quantities of added sugar compared to unaware adults, including no differences observed by age, sex, and race/Hispanic origin.
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Estado Prediabético , Adulto , Masculino , Humanos , Estados Unidos/epidemiología , Estado Prediabético/epidemiología , Estado Prediabético/diagnóstico , Encuestas Nutricionales , Azúcares , Autoinforme , Estudios Transversales , Azúcares de la DietaRESUMEN
We assessed a ketogenic diet (KD) intervention protocol and the cognitive effects of KD in older adults with HIV-associated neurocognitive impairment. Adults older than 50 years and living with HIV and mild-to-moderate neurocognitive impairment were randomized to either a KD or a patient-choice diet for 12 weeks followed by a 6-week washout period. A neurocognitive battery was administered at baseline, Week 12, and Week 18. Paired t tests compared groups at baseline, and multivariate analyses of covariance were used to assess between-group differences on primary outcome variables at Weeks 12 and 18. We enrolled 17 participants, and 14 completed the study. No between-group baseline differences were noted. The KD group demonstrated improved executive function and speed of processing at Week 12, which were negated after participants resumed their usual diets. Our study supports the potential efficacy of a KD for the treatment of HIV-associated neurocognitive impairment.
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Cognición/fisiología , Envejecimiento Cognitivo , Disfunción Cognitiva/dietoterapia , Dieta Cetogénica , Infecciones por VIH/psicología , Anciano , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/psicología , Dieta Cetogénica/efectos adversos , Función Ejecutiva , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Evaluación de Resultado en la Atención de Salud , Cooperación del Paciente , Proyectos PilotoRESUMEN
AIM: The aim of this study is to describe the concept added sugar in the context of type 2 diabetes (T2D) risk in adults. BACKGROUND: Dietary added sugars are associated with a greater risk for T2D; however, it is unclear if added sugars influence T2D risk directly or if their effects are mediated by excess caloric intake and weight gain. DESIGN: A principle-based concept analysis following the PRISMA guidelines was conducted to clarify the concept of added sugar. A systematic search was conducted using PubMed and Embase. Multidisciplinary, empirical evidence was appraised using four guiding principles outlined by the principle-based concept analysis method. RESULTS: Thirty-five publications were included in this concept analysis. The concept, added sugar in the context of T2D risk, was found to be epistemologically immature and lacked conceptual clarity. CONCLUSIONS: Added sugar is an immature concept warranting further refinement for conceptual advancement. To enhance conceptual clarity, the term "added sugar" should be used consistently in the scientific literature when discussing foods or beverages containing added sugars or caloric sweeteners. A clearer delineation of added sugar and its association with T2D risk in adults is critical to advance this concept within the scientific literature.
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Formación de Concepto , Diabetes Mellitus Tipo 2/dietoterapia , Azúcares de la Dieta/efectos adversos , Economía , Adulto , Diabetes Mellitus Tipo 2/fisiopatología , Diabetes Mellitus Tipo 2/psicología , Azúcares de la Dieta/metabolismo , Femenino , Humanos , MasculinoRESUMEN
The synergistic effects of HIV and aging on the brain may compromise cognitive reserve, resulting in HIV-associated neurocognitive disorder. The neuroscience literature suggests that computerized cognitive training programs represent a practical strategy to protect or remediate cognitive functioning in older adults. Such cognitive training programs may hold similar therapeutic benefits for adults living with HIV. This systematic review evaluated the effects of cognitive training interventions in adults living with HIV. This systematic review includes 13 studies that have been conducted or are being conducted. Results suggest that cognitive training may improve the cognitive domain that is the target of training. One case study even demonstrated a reversal of HIV-associated neurocognitive disorder after cognitive training. Although greater evidence is needed to establish treatment guidelines, current evidence suggests that cognitive training improves cognitive function, which translates to more optimal everyday functioning (i.e., driving), improved mood, greater locus of control, and enhanced quality of life.
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Actividades Cotidianas/psicología , Cognición/fisiología , Reserva Cognitiva/fisiología , Infecciones por VIH/psicología , Trastornos Neurocognitivos/diagnóstico , Calidad de Vida , Anciano , Infecciones por VIH/complicaciones , Humanos , Trastornos Neurocognitivos/complicaciones , Trastornos Neurocognitivos/psicología , Pruebas NeuropsicológicasRESUMEN
It has been suggested that self-efficacy specific to parenting or feeding may influence the decisions parents make regarding infant feeding; however, a review of this topic has not been conducted. The purpose of this integrative review is to synthesize the literature regarding the potential role of self-efficacy in infant feeding practices or infant weight gain. A total of 40 articles were used to guide this review, which were classified into three categories examining an association with self-efficacy (1) breastfeeding; (2) infant feeding practices such as parental feeding style and dietary quality; and (3) infant weight gain. Evidence regarding breastfeeding self-efficacy (BFSE) and breastfeeding is extensive; mothers with a higher sense of BFSE more often initiate breastfeeding and breastfeed for longer durations. The evidence regarding self-efficacy and the association with infant feeding practices other than breastfeeding is sparse. However, several studies report that mothers who have a higher sense of self-efficacy are more likely to follow infant feeding practices which align with recommendations. The authors have speculated an association between self-efficacy and infant weight gain; yet, to date, no study has found a significant association. More research is needed on the topic, particularly in diverse populations and with fathers and mothers.
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Lactancia Materna/psicología , Autoeficacia , Aumento de Peso , Conducta Alimentaria , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Padres/psicologíaRESUMEN
Mitochondrial dysfunction is associated with abnormal glucose metabolism, inflammation and greater oxidative stress in the brain, each of which may contribute uniquely and perhaps synergistically to HIV-Associated Neurocognitive Disorders (HAND) risk. The ketogenic (i.e., low carbohydrate) diet provides the brain with a highly efficient mitochondrial fuel and is associated with improved cognitive performance in older adults with impaired neurocognitive functioning secondary to ageing, Alzheimer's, and Parkinson's disease; however, whether these cognitive gains are generalizable to older adults with HAND is unknown. Thus, the process and cognitive outcomes of the first participant randomized to the intervention and to the control group were investigated in this case-comparison study. To our knowledge, this is first report to establish the plausibility of the ketogenic diet as a treatment for HAND.
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Nanoparticulate ferrites such as manganese zinc ferrite and nickel zinc ferrite hold great promise for advanced applications in power electronics. The use of these materials in current applications requires fine control over the nanoparticle size as well as size distribution to maximize their packing density. While there are several techniques for the synthesis of ferrite nanoparticles, reverse micelle techniques provide the greatest flexibility and control over size, crystallinity, and magnetic properties. Recipes for the synthesis of manganese zinc ferrite, nickel zinc ferrite, and an enhanced ferrite are presented along with analysis of the crystalline and magnetic properties. Comparisons are made on the quality of nanoparticles produced using different surfactant systems. The importance of various reaction conditions is explored with a discussion on the corresponding effects on the magnetic properties, particle morphology, stoichiometry, crystallinity, and phase purity.