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1.
medRxiv ; 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38978676

RESUMEN

Background: One approach to test for differential associations between plant foods with health uses a scoring approach: foods categorized into animal or 'healthy' plant-based or 'unhealthy' plant-based groups to construct a plant-based diet index (PDI), healthy PDI (hPDI), and unhealthy PDI (uPDI). Objective: To evaluate robustness of associations between diet indices and incident coronary heart disease (CHD) risk when recategorizing food groups in indices. Methods: Using REasons for Geographic and Racial Differences in Stroke (REGARDS) data, we replicated a published use of the scoring approach. Using Cox proportional hazards regression, we assessed ramifications of the following on associations between diet indices and CHD risk: 1) reconfiguring foods within and among food groups, using potatoes as an example, 2) leave-one-out analysis for each of 12 plant-based food groups, and 3) agnostically redefining each food group as 'healthy' or 'unhealthy'. Results: Over 153,286 person-years of follow-up, there were 868 cases of CHD. Replication analyses did not reach statistical significance. General patterns of magnitude of hazard ratios (HRs) in replication and reconfiguration models were PDI HRs < hPDI HRs < uPDI HRs for women, and hPDI < PDI < uPDI for men. Five models reconfiguring potatoes resulted in small, varied differences in PDI, hPDI, and uPDI associations. Leave-one-out analyses resulted in greater variation of associations between indices and CHD. In agnostic models, each plant-based food group was classified in indices as 'healthy' and 'unhealthy' with statistically significant beneficial or deleterious associations with CHD. Averaged over 4,096 models, HRs' shifts were small when food groups were moved between 'healthy' and 'unhealthy'. Conclusion: Statistically significant associations between hPDI, uPDI, and PDI and incident CHD were not replicated. Small perturbations of the scoring approach had varied impacts on HRs. Agnostically constructing diet indices demonstrated the potential for guilt (or benefit) by association: any of the food groups we studied could be categorized with others in an index showing beneficial or deleterious associations.

2.
Geroscience ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850387

RESUMEN

Caloric restriction (CR) results in reduced energy and protein intake, raising questions about protein restriction's contribution to CR longevity benefits. We kept ad libitum (AL)-fed male C57BL/6J mice at 27°C (AL27) and pair-fed (PF) mice at 22°C (22(PF27)). The 22(PF27) group was fed to match AL27 while restricted for calories due to cold-induced metabolism. The 22(PF27) mice had significantly lower body weight, lean mass, fat mass, leptin, IGF-1, and TNF-α levels than AL27 mice (p<0.001 for all). Manipulations over ~11 weeks resulted in significant differences in body temperature, physical activity, and expression of key genes linked to hunger in the hypothalamus. Survival was significantly greater in 22(PF27) compared to AL27 overall (p<0.001). CR in the context of equivalent energy and protein intake resulted in hormonal, metabolic, and physiological benefits and extended longevity. Hence, energy imbalance, rather than low energy or protein intake per se, mediates the benefits of CR.

3.
Obesity (Silver Spring) ; 32(5): 959-968, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38600047

RESUMEN

OBJECTIVE: The objective of this study was to investigate body composition changes with weight cycling (WC) among adult C57BL/6J mice with diet-induced obesity. METHODS: A total of 555 single-housed mice were fed a high-fat diet ad libitum (AL) from 8 to 43 weeks of age. The 200 heaviest mice of each sex were randomized to the following four groups: ever obese (EO, continued AL feeding); obese weight loser (OWL, calorie-restricted); obese weight loser moderate (OWLM, body weight halfway between EO and OWL); and WC (diet restricted to OWL followed by AL refeeding cycles). Body weight and composition data were collected. Linear regression was used to calculate residuals between predicted and observed fat mass. Linear mixed models were used to compare diet groups. RESULTS: Although weight loss and regain resulted in changes in body weight and composition, fat mass, body weight, and relative body fat were not significantly greater for the WC group compared with the EO group. During long-term calorie restriction, males (but not females) in the OWLM group remained relatively fatter than the EO group. CONCLUSIONS: WC did not increase body weight or relative fat mass for middle-aged, high-fat diet-fed adult mice. However, long-term moderate calorie restriction resulted in lower body weight but greater "relative" fat in male mice.

4.
PEC Innov ; 3: 100237, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38148854

RESUMEN

Objective: Adequate physician-patient communication about cancer recurrence is vital to quality of life and to informed decision-making related to survivorship care. The current study was guided by a cognitive-affective framework to examine communication with family and physicians about breast cancer recurrence risk. Methods: A survey of recently-diagnosed, early-stage breast cancer patients in Appalachia investigated physician-patient and familial communication about breast cancer recurrence risk. Results: Over 30% of participants reported not talking to family or physicians about breast cancer recurrence risk. Younger patients reported more conversations, and speaking with physicians was associated with greater perception risk factors associated with recurrence risk. Greater worry about recurrence was associated with more communication with family and plans to talk to family, physicians, and friends about recurrence risk in the future. Conclusion: Additional supports for patients and physicians are needed to improve understanding of breast cancer recurrence risk and risk factors for recurrence. Innovation: Family communication about breast cancer recurrence risk is understudied. The combination of physician and family communication adds novelty to our analysis.

5.
Nutrients ; 15(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37960171

RESUMEN

The purpose of the study is to assess the impact of partial meat replacement with walnuts using a dose-escalation approach on nutrient intake and diet quality in the usual US diet. Food modeling was implemented using the nationally representative 2015-2018 National Health and Examination Survey (NHANES), with a focus on non-nut consumers, which included 2707 children and adolescents and 5190 adults. Walnuts replaced meat in a dose-escalating manner (0.5, 1, 1.5, and 2 oz walnuts per day replaced 1, 2, 3, and 4 oz meat, respectively). Diet quality was estimated using the population ratio method of the 2015 Healthy Eating Index. The usual intake of nutrients was estimated using the National Cancer Institute method. Significant differences were determined using non-overlapping 95% confidence intervals. The partial replacement of meat with walnuts demonstrated significant increases in the mean intake of fiber, magnesium, and omega-3 fatty acids and significant decreases in cholesterol and vitamin B12 in the modeled diets for children, adolescents, and adults. Additionally, the partial replacement of meat with walnuts improved overall diet quality. Walnut consumption at 1-2 oz as a replacement for some meat may improve nutrient intake and diet quality across age groups.


Asunto(s)
Juglans , Adulto , Niño , Adolescente , Humanos , Estados Unidos , Encuestas Nutricionales , Dieta , Ingestión de Energía , Carne , Nutrientes
6.
J Trace Elem Med Biol ; 80: 127310, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37801789

RESUMEN

OBJECTIVES: High-dose oral iron supplementation for patients who develop iron deficiency after bariatric surgery may induce oxidative stress in the gastrointestine. The study's objective was to test this hypothesis by determining the impact of high-dose oral iron on systemic oxidative stress. METHODS: We used archived plasma samples from a randomized controlled clinical trial (NCT02404012) comparing FeSO4 (195 mg/day, NatureMade®, West Hills, CA) with a heme iron polypeptide (HIP, 60.4 mg/day, Proferrin®, Colorado Biolabs, Lafayette, CO) for 8 weeks. Systemic oxidative stress was measured using malondialdehyde and total antioxidant capacity (MDA, Abcam, ab238537 and TAC, Abcam, ab65329 Cambridge, UK) assays. Data was log-transformed and presented as means and standard deviations; a mixed model was used to determine the effects of time (0, 2, 4, and 8 weeks) and treatment (FeSO4 versus HIP) on oxidative stress. RESULTS: The FeSO4 (N = 8) and HIP (N = 5) participants were balanced in body mass index (35.0 ± 5.5 kg/m2), race (93 % White), time post-surgery (7.3 ± 3.3 years), as well as serum concentrations of iron (P > 0.05). The FeSO4 group tended to be older (44.3 ± 4.5 years) and they had lower concentrations of serum ferritin (6.5 ± 2.7 µg/mL) than the HIP (38.2 ± 9.3 years, and 12.9 ± 16.8 µg/mL) group (P = 0.080, and P = 0.017 respectively). We observed a larger increase in serum iron in the FeSO4 group during the 8 weeks of Fe supplementation, compared to that in the HIP group (p = 0.004). We observed a decreasing trend in MDA over the 8 weeks (p = 0.080) in the FeSO4 treatment group. There were no significant differences in TAC between and within FeSO4 and HIP groups over the 8 week supplementation period. CONCLUSIONS: This preliminary study suggests that high-dose oral iron supplementation for iron deficiency does not adversely impact systemic oxidative stress in patients undergoing bariatric surgery.


Asunto(s)
Cirugía Bariátrica , Deficiencias de Hierro , Humanos , Hierro , Estrés Oxidativo , Suplementos Dietéticos
9.
Prev Sci ; 24(7): 1275-1291, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37178346

RESUMEN

Evidence-based policy uses intervention research to inform consequential decisions about resource allocation. Research findings are often published in peer-reviewed journals. Because detrimental research practices associated with closed science are common, journal articles report more false-positives and exaggerated effect sizes than would be desirable. Journal implementation of standards that promote open science-such as the transparency and openness promotion (TOP) guidelines-could reduce detrimental research practices and improve the trustworthiness of research evidence on intervention effectiveness. We evaluated TOP implementation at 339 peer-reviewed journals that have been used to identify evidence-based interventions for policymaking and programmatic decisions. Each of ten open science standards in TOP was not implemented in most journals' policies (instructions to authors), procedures (manuscript submission systems), or practices (published articles). Journals implementing at least one standard typically encouraged, but did not require, an open science practice. We discuss why and how journals could improve implementation of open science standards to safeguard evidence-based policy.

11.
AIDS Behav ; 27(10): 3447-3459, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37052786

RESUMEN

Access to social support from one's social network can serve as a protective factor against HIV infection; however, research exploring the availability of support in diverse populations that include high proportions of people at increased risk for HIV and the characteristics of network members associated with access to such support is limited. Multi-level dyadic analyses of social network data collected from women at risk for HIV and their network members reveal which individual and relationship characteristics of network members are associated with providing emotional, material, and/or health informational support. Results indicate that access to all three types of support was associated with a network member being a friend, a member of a participant's 'core' group, someone whose opinion matters to the respondent, and the respondent trusting them. These findings have implications for interventions designed to increase access to support among individuals at risk for HIV.


Asunto(s)
Infecciones por VIH , Humanos , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Infecciones por VIH/complicaciones , Apoyo Social
12.
Aging (Albany NY) ; 15(6): 1748-1767, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36947702

RESUMEN

Aging is accompanied by increased susceptibility to infections including with viral pathogens resulting in higher morbidity and mortality among the elderly. Significant changes in host metabolism can take place following virus infection. Efficient immune responses are energetically costly, and viruses divert host molecular resources to promote their own replication. Virus-induced metabolic reprogramming could impact infection outcomes, however, how this is affected by aging and impacts organismal survival remains poorly understood. RNA virus infection of Drosophila melanogaster with Flock House virus (FHV) is an effective model to study antiviral responses with age, where older flies die faster than younger flies due to impaired disease tolerance. Using this aged host-virus model, we conducted longitudinal, single-fly respirometry studies to determine if metabolism impacts infection outcomes. Analysis using linear mixed models on Oxygen Consumption Rate (OCR) following the first 72-hours post-infection showed that FHV modulates respiration, but age has no significant effect on OCR. However, the longitudinal assessment revealed that OCR in young flies progressively and significantly decreases, while OCR in aged flies remains constant throughout the three days of the experiment. Furthermore, we found that the OCR signature at 24-hours varied in response to both experimental treatment and survival status. FHV-injected flies that died prior to 48- or 72-hours measurements had a lower OCR compared to survivors at 48-hours. Our findings suggest the host's metabolic profile could influence the outcome of viral infections.


Asunto(s)
Nodaviridae , Virus ARN , Virosis , Animales , Masculino , Drosophila melanogaster/genética , Virus ARN/genética , Nodaviridae/genética , Consumo de Oxígeno
13.
Aging Cell ; 22(4): e13787, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36734122

RESUMEN

Interventions for animal lifespan extension like caloric restriction (CR) have identified physiologic and biochemical pathways related to hunger and energy-sensing status as possible contributors, but mechanisms have not been fully elucidated. Prior studies using ghrelin agonists show greater food intake but no effect on lifespan in rodent models. This experiment in male C57BL/6J mice tested the influence of ghrelin agonism for perceived hunger, in the absence of CR, on longevity. Mice aged 4 weeks were allowed to acclimate for 2 weeks prior to being assigned (N = 60/group). Prior to lights off daily (12:12 cycle), animals were fed a ghrelin agonist pill (LY444711; Eli Lilly) or a placebo control (Ctrl) until death. Treatment (GhrAg) animals were pair-fed daily based on the group mean food intake consumed by Ctrl (ad libitum feeding) the prior week. Results indicate an increased lifespan effect (log-rank p = 0.0032) for GhrAg versus placebo Ctrl, which weighed significantly more than GhrAg (adjusted for baseline weight). Further studies are needed to determine the full scope of effects of this ghrelin agonist, either directly via increased ghrelin receptor signaling or indirectly via other hypothalamic, systemic, or tissue-specific mechanisms.


Asunto(s)
Ghrelina , Longevidad , Animales , Masculino , Ratones , Restricción Calórica , Ghrelina/agonistas , Ratones Endogámicos C57BL
14.
R Soc Open Sci ; 10(2): 221093, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36756061

RESUMEN

The Transparency and Openness Promotion (TOP) Guidelines provide a framework to help journals develop open science policies. Theories of behaviour change can guide understanding of why journals do (not) implement open science policies and the development of interventions to improve these policies. In this study, we used the Theoretical Domains Framework to survey 88 journal editors on their capability, opportunity and motivation to implement TOP. Likert-scale questions assessed editor support for TOP, and enablers and barriers to implementing TOP. A qualitative question asked editors to provide reflections on their ratings. Most participating editors supported adopting TOP at their journal (71%) and perceived other editors in their discipline to support adopting TOP (57%). Most editors (93%) agreed their roles include maintaining policies that reflect current best practices. However, most editors (74%) did not see implementing TOP as a high priority compared with other editorial responsibilities. Qualitative responses expressed structural barriers to implementing TOP (e.g. lack of time, resources and authority to implement changes) and varying support for TOP depending on study type, open science standard, and level of implementation. We discuss how these findings could inform the development of theoretically guided interventions to increase open science policies, procedures and practices.

15.
Nutrients ; 15(2)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36678128

RESUMEN

BACKGROUND: The under-consumption of calcium, potassium, fiber, and vitamin D is considered a U.S. public health concern. Shifts in eating patterns that increase the consumption of vegetables, fruits, whole grains, nuts/seeds, and dairy products can help achieve the recommended intakes of these nutrients, leading to healthier diets. OBJECTIVE: We assessed the impact of adding 1 ounce (28.35 g) of walnuts to usual diets on diet quality and nutrients of concern, including magnesium, fiber, and potassium. METHODS: We utilized 24 h dietary recalls obtained from the What We Eat in America, National Health and Nutrition Examination Survey (NHANES) and modeled the addition of 1 ounce (28.35 g) of walnuts to the usual diets of no-nut consumers. No-nut consumers aged ≥4 years (n = 7757) from the 2015-2018 NHANES study were included. Population percentages with intakes below the estimated average requirement (EAR) values for calcium, magnesium, folate, and vitamin E and above the adequate intake (AI) values for potassium and fiber were examined. Diet quality was assessed using the Healthy Eating Index-2015 (HEI-2015). The National Cancer Institute method was used to estimate the usual and modeled intakes. Significant differences between usual (current) and modeled intakes were determined using non-overlapping 95% confidence intervals. All analyses included sample weights to account for the NHANES survey design. RESULTS: Adding 1 ounce (28.35 g) of walnuts to the usual diet resulted in significant reductions in the percentages of adults with intakes below the EAR for magnesium and folate (69.6% vs. 52.0%; 49.2% vs. 40.6%, respectively), and increased the percentage of adults above the AI for potassium (22.8% vs. 26.5%). A similar trend was observed among children (4-18 years). HEI scores improved significantly from 49.1 (95% CI: 48.0-50.4) to 58.5 (95% CI: 57.5-59.6) in children and from 52.4 (95% CI: 51.0-53.8) to 59.2 (95% CI: 58.0-60.5) in adults. CONCLUSIONS: Adding 1 ounce (28.35 g) of walnuts to the usual diet of no-nut consumers improved the diet quality and adequacy of some under-consumed nutrients.


Asunto(s)
Juglans , Nueces , Adulto , Niño , Humanos , Estados Unidos , Encuestas Nutricionales , Magnesio , Calcio , Dieta , Calcio de la Dieta , Ácido Fólico , Potasio
18.
J Nutr ; 151(3): 482-490, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-33274750

RESUMEN

BACKGROUND: The effect of macronutrient composition on total energy expenditure (TEE) remains controversial, with divergent findings among studies. One source of heterogeneity may be study duration, as physiological adaptation to lower carbohydrate intake may require 2 to 3 wk. OBJECTIVE: We tested the hypothesis that the effects of carbohydrate [expressed as % of energy intake (EI)] on TEE vary with time. METHODS: The sample included trials from a previous meta-analysis and new trials identified in a PubMed search through 9 March 2020 comparing lower- and higher-carbohydrate diets, controlled for EI or body weight. Three reviewers independently extracted data and reconciled discrepancies. Effects on TEE were pooled using inverse-variance-weighted meta-analysis, with between-study heterogeneity assessed using the I2 statistic. Meta-regression was used to quantify the influence of study duration, dichotomized at 2.5 wk. RESULTS: The 29 trials ranged in duration from 1 to 140 d (median: 4 d) and included 617 participants. Difference in carbohydrate between intervention arms ranged from 8% to 77% EI (median: 30%). Compared with reported findings in the prior analysis (I2 = 32.2%), we found greater heterogeneity (I2 = 90.9% in the reanalysis, 81.6% in the updated analysis). Study duration modified the diet effect on TEE (P < 0.001). Among 23 shorter trials, TEE was reduced on lower-carbohydrate diets (-50.0 kcal/d; 95% CI: -77.4, -22.6 kcal/d) with substantial heterogeneity (I2 = 69.8). Among 6 longer trials, TEE was increased on low-carbohydrate diets (135.4 kcal/d; 95% CI: 72.0, 198.7 kcal/d) with low heterogeneity (I2 = 26.4). Expressed per 10% decrease in carbohydrate as %EI, the TEE effects in shorter and longer trials were -14.5 kcal/d and 50.4 kcal/d, respectively. Findings were materially unchanged in sensitivity analyses. CONCLUSIONS: Lower-carbohydrate diets transiently reduce TEE, with a larger increase after ∼2.5 wk. These findings highlight the importance of longer trials to understand chronic macronutrient effects and suggest a mechanism whereby lower-carbohydrate diets may facilitate weight loss.


Asunto(s)
Ensayos Clínicos como Asunto , Dieta de Carga de Carbohidratos , Dieta Baja en Carbohidratos , Carbohidratos de la Dieta/metabolismo , Ingestión de Energía , Metabolismo Energético , Peso Corporal , Duración de la Terapia , Humanos , Obesidad/metabolismo
19.
Am J Lifestyle Med ; 14(2): 204-215, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32231486

RESUMEN

Sedentary behavior is highly prevalent despite growing evidence of adverse effects on the cardiovascular and metabolic system that are independent of the level of recreational physical activity (PA). We present results for the association between sitting time and cardiovascular disease (CVD) from selected cohort and cross-sectional studies published in or after the year 2010 according to the domains where sitting time is accumulated during the day. These include TV viewing, occupational sitting, and sitting during transportation as well as overall sitting. The outcomes considered in this review are total CVD, coronary heart disease, and stroke as well as CVD risk factors-namely, hypertension, hypercholesterolemia, and type 2 diabetes and their associated biomarkers. Finally, several current issues with regard to studying the effects of sitting time on CVD are discussed, including how sedentary behavior is assessed, isotemporal substitution modeling, examination of joint associations for sitting and PA, and benefits of breaks in sitting time. Overall, the scientific evidence supports public health recommendations that encourage adults to limit their sedentary time in order to improve their cardiovascular health.

20.
Nutrition ; 54: 1-6, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29674230

RESUMEN

OBJECTIVES: Our objective was to investigate the association between herbal/botanic supplement use and perceived quality of life (QoL), cancer recurrence, and all-cause mortality in colon cancer patients. METHODS: Patients (n = 453) newly diagnosed with stage II adenocarcinoma of the colon between 2009 and 2011 were recruited from the North Carolina Central Cancer Registry. Data including demographic variables, herbal medicine use and frequency, lifestyle, diet, cancer treatment, and QoL were collected by interviews at diagnosis (baseline) and 1 and 2 y after diagnosis. Mortality information was obtained via the National Death Index. The Functional Assessment of Cancer Therapy-Colorectal (FACT-C) and Medical Outcomes Short Form 12 (SF-12) were used to evaluate QoL. RESULTS: At baseline, herbal/botanic supplement users were more likely to have a healthier lifestyle than non-users, including more physical activity (P <0.01), more fruit and vegetable consumption (P = 0.01), less smoking (P <0.01), and less energy intake from fat (P = 0.02). After adjustment for potential confounders, no significant association was found between herbal/botanic supplement use and QoL assessed by FACT-C and SF-12. Similarly, herbal/botanic supplement use was not associated with the risk of recurrence, all-cause mortality or the combined. CONCLUSION: In this study, patients with stage II colon cancer using herbal/botanic supplements had no significant improvement in their QoL and no difference in odds of colon cancer recurrence and all-cause mortality over 2 y after diagnosis compared with those who did not use herbs/botanicals. Further studies are warranted to confirm the findings and to focus on types of herbal/botanic supplements.


Asunto(s)
Adenocarcinoma/terapia , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias del Colon/terapia , Suplementos Dietéticos/estadística & datos numéricos , Recurrencia Local de Neoplasia/etiología , Calidad de Vida , Adenocarcinoma/mortalidad , Adenocarcinoma/psicología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/mortalidad , Neoplasias del Colon/psicología , Femenino , Estudios de Seguimiento , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , North Carolina , Sistema de Registros
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