Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Nutrients ; 15(5)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36904244

RESUMEN

Omega-3 fatty acids (w3FAs) have demonstrated benefits in several inflammatory disease states; however, limited research has been conducted in sickle cell disease (SCD). While marine-based w3FAs are used, their strong odor and taste are a barrier to long-term use. Plant-based sources, especially those in whole foods, may circumvent this barrier. We tested whether flaxseed (rich source of w3FAs) was acceptable to children with SCD. A cross-sectional tasting trial of flaxseed added to baked products (cookies, pancakes, brownies) or to readily available foods (applesauce, pudding, yogurt) was conducted among 30 children (median age = 13 years) reporting to a clinic for routine follow-up, sick visits, or transfusion for SCD to determine acceptability. A food preference rank scale (1-7) was used to rank products based on taste, sight, smell, and texture. An average score for each product was computed. Children were also asked to rank their top three products. The top-ranked products were flaxseed baked in brownies and cookies and ground flaxseed added to yogurt. More than 80% of participants indicated willingness to be contacted for a follow-up study in which a flaxseed-supplemented diet would be evaluated for mitigation of SCD-associated pain. In conclusion, flaxseed-enriched products are palatable and acceptable in children with SCD.


Asunto(s)
Anemia de Células Falciformes , Lino , Humanos , Niño , Adolescente , Alimentos Fortificados , Estudios Transversales , Estudios de Seguimiento
2.
Nutr Res ; 105: 154-162, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36049380

RESUMEN

Dual-energy x-ray absorptiometry (DXA) is considered to have high accuracy in estimating fat mass; however, DXA is not always available. We hypothesized that the equations most commonly used for predicting body fat percentage (BF%) using skinfold thickness agree with direct measures of BF% obtained by DXA scan in African American (AA) and Caucasian American (CA) women. Data from 42 women from Alabama who were 21 to 45 years of age, who self-identify as AA (n = 20) or CA (n = 22) were included. BF% was estimated using DXA scan and through 6 different skinfold thickness equations. Agreement between DXA-BF% and BF% based on the skinfold thickness equations was assessed following the Bland-Altman method (bias and agreement limits). Agreement analysis showed in both AA and CA women that the BF%-Siri equation reflects better agreement and lower mean differences (bias) with BF%-DXA than the BF%-Brozek equation after applying 4 body density (BD) equations. Limits showed that BF%-Siri and BF%-Brozek predictive equations overestimate BF% compared with DXA-BF% in both AA and CA women. In AAs, equations that overestimated less were Wilmore and Behnke-Siri (by 1.81%) and Durnin and Womersley-Siri (by 2.5%) equations. Regarding CAs, equations that overestimated less were Durnin and Womersley-Siri (by 2.74%) and Wilmore and Behnke-Siri (by 3.11%) equations. The results of this study show that the BF%-Siri equation is a more accurate alternative than the BF%-Brozek equation for the calculation of BF%. In the calculation of BD, the Wilmore and Behnke equation in AA women and Durnin and Womersley in CA women were those that overestimated BF% to a lesser degree.


Asunto(s)
Negro o Afroamericano , Composición Corporal , Absorciometría de Fotón , Tejido Adiposo/diagnóstico por imagen , Antropometría , Femenino , Humanos , Grosor de los Pliegues Cutáneos
3.
J Clin Rheumatol ; 26(4): 147-156, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32453288

RESUMEN

OBJECTIVE: The aim of this study was to conduct a 9-month pilot Internet randomized controlled trial (RCT) of cherry extract and diet modification in gout to assess the feasibility of an Internet study and obtain effect estimates. METHODS: After providing online informed consent in response to Internet advertisements and social media or clinic flyers, 84 people with physician-confirmed gout were randomized to either cherry extract 3,600 mg/d (n = 41) or dietitian-assisted diet modification for gout (n = 43). All study outcomes were collected via Internet and phone calls. The primary objective was the feasibility of an Internet study, and secondary objectives were to obtain effect estimates for gout flares, functional ability assessed with the Health Assessment Questionnaire (HAQ), and adverse events (AEs) for future trials. RESULTS: Of the 84 people randomized, overall completion rates were more than 80% for most study procedures up to 6 months and similar for the 2 active comparators. Improvements were seen in gout flares and HAQ scores in cherry extract and diet modification groups at 9 months compared with baseline: gout flares per month, 0.22 versus 0.36 (p = 0.049) and 0.28 versus 0.31 (p = 0.76); proportion with any gout flare, 56% versus 98% (p < 0.0001) and 65% versus 98% (p = 0.0002); and mean ± standard deviation HAQ score, 0.28 ± 0.54 versus 0.55 ± 0.68 (p = 0.001) and 0.23 ± 0.40 versus 0.48 ± 0.61 (p = 0.06), respectively. Any AEs and gastrointestinal symptoms/AEs at 9 months in cherry extract and diet modification groups were 3% versus 0% and 28% versus 27%, respectively. CONCLUSIONS: An Internet gout RCT is feasible for nonpharmacological gout treatments. A hypothesis-testing, large Internet RCT of cherry extract versus placebo is needed.


Asunto(s)
Autoevaluación Diagnóstica , Dietoterapia/métodos , Estado Funcional , Gota/terapia , Extractos Vegetales , Prunus domestica , Cápsulas , Estudios de Factibilidad , Femenino , Gota/diagnóstico , Gota/dietoterapia , Humanos , Intervención basada en la Internet , Masculino , Persona de Mediana Edad , Fitoterapia/métodos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/efectos adversos , Evaluación de Síntomas/métodos , Brote de los Síntomas , Resultado del Tratamiento
4.
J Clin Rheumatol ; 26(5): 181-191, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30870252

RESUMEN

OBJECTIVE: The aim of this study was to report patient-centered outcomes and finalization of key study procedures from a 9-month pilot internet randomized controlled trial of cherry extract versus diet modification. METHODS: We randomized 84 people with physician-confirmed gout in an internet study to cherry extract (n = 41) or dietitian-assisted diet modification for gout (n = 43). All study outcomes were collected via internet and phone calls. We finalized key study procedures. We assessed acceptability and feasibility of the intervention and satisfaction with study website. RESULTS: Study participant satisfaction with the intervention was high. The intervention was perceived as easy, enjoyable, understandable, and helpful (scores 65-88 for all; higher = better). The amount of time spent for the study was acceptable. Participant satisfaction with website interaction and content was very high; 85% or more were moderately to extremely satisfied. Significantly lower total calories, total carbohydrate, and saturated fat intake were noted at 6 months in the diet modification versus cherry extract group; differences were insignificant at 9 months. Six of the 8 Health Assessment Questionnaire sections/domains improved significantly from baseline to 9 months in cherry extract versus 2 Health Assessment Questionnaire sections/domains in the diet modification group. Key study procedures were finalized for a future trial, including an internet diet assessment tool, gout flare assessment, provider confirmation of gout diagnosis, patient reporting of classification criteria, and centralized laboratory-assisted serum urate testing. CONCLUSIONS: High patient acceptability and feasibility of study/intervention and finalization of key study procedures indicate that hypothesis-testing internet gout trials of cherry extract and/or diet modification can be conducted in the future.


Asunto(s)
Gota , Extractos Vegetales , Estudios de Factibilidad , Gota/diagnóstico , Gota/terapia , Humanos , Atención Dirigida al Paciente , Extractos Vegetales/uso terapéutico , Brote de los Síntomas
5.
Nutr Cancer ; 68(6): 926-34, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27341142

RESUMEN

Glioblastoma multiforme (GBM) is rare, yet it is the most common brain malignancy and has a poor prognosis. In regard to GBM, there is a dearth of research on resting energy expenditure (REE) and the accuracy of extant prediction equations. The aim of this cross-sectional study was to compare measured REE (mREE) to commonly used prediction equations in newly diagnosed GBM patients. REE was collected by indirect calorimetry in 20 GBM patients. Calculated REE was derived from Harris-Benedict (again with weight adjusted for obesity), Mifflin-St Jeor, and the 20 kcal/kg body weight ratio method. Paired t-tests and Bland-Altman analyses were used to compare group means, evaluate the bias, and find the limits of agreement. Clinical accuracy was assessed by determining the percentage of patients with predicted REE within ±10% of mREE. Subjects were evenly distributed with regard to gender, primarily Caucasian, and largely overweight or obese and had a mean age of 57 years. All equations overestimated mREE. Mifflin-St Jeor and adjusted Harris-Benedict had the narrowest limits of agreement and accurately predicted 60% and 65% of subjects, respectively. Clinicians should be aware of the discrepancy between commonly used prediction equations and REE. More research is needed to verify these findings and decipher the cause and significance in the GBM population.


Asunto(s)
Metabolismo Basal , Ingestión de Energía , Glioblastoma/metabolismo , Desnutrición/prevención & control , Evaluación Nutricional , Necesidades Nutricionales , Sobrepeso/dietoterapia , Alabama , Algoritmos , Índice de Masa Corporal , Estudios Transversales , Estudios de Factibilidad , Femenino , Glioblastoma/complicaciones , Glioblastoma/patología , Hospitales Universitarios , Humanos , Estudios Longitudinales , Masculino , Desnutrición/complicaciones , Persona de Mediana Edad , Clasificación del Tumor , Servicio Ambulatorio en Hospital , Sobrepeso/complicaciones , Proyectos Piloto , Reproducibilidad de los Resultados
7.
Nutr Metab (Lond) ; 13: 2, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26766961

RESUMEN

BACKGROUND: Resistant starch (RS) is a type of dietary fiber that can improve glucose metabolism, but its effects may be modulated by sex or baseline insulin sensitivity. This study was designed to examine the effect of high-amylose maize resistant starch (HAM-RS2) on insulin sensitivity (SI) in women, and to determine if SI status affects the response to RS. METHODS: This was a randomized, placebo-controlled, double-blind, cross-over study. Participants were 40 healthy, non-diabetic women aged 22-67 years in the normal-weight to obese BMI range (20.6-47.4 kg/m(2)). Two doses of HAM-RS2 were tested, 15 and 30 g per day, administered in the form of cookies. Participants were randomized to the order in which they received the experimental and placebo product. Each arm was 4 weeks, with a 4-week wash-out period in between. SI was assessed at the end of each 4-week arm of product consumption by frequently-sampled, insulin-modified, intravenous glucose tolerance test and minimal modeling. Participants were categorized as being insulin resistant (IR; SI < 7.8) or insulin sensitive (IS; SI ≥ 7.8) based on Gaussian analysis. The effect of treatment arm on SI was examined by mixed-model analysis within IR and IS sub-groups, using all available data. In addition, SI was examined by ANOVA among just those women who completed all three arms of the study with valid SI results. RESULTS: Among IR participants, SI was on average ~16 % higher after the 30 g arm when compared to the control arm by mixed-model analysis (n = 40, P < 0.05), and tended to be 23 % higher by ANOVA among women who completed all arms (n = 23, P = 0.06). HAM-RS2 did not affect SI in IS women. CONCLUSION: Consumption of HAM-RS2 at 30 g/day in the form of a snack food item was associated with improved insulin sensitivity in women with insulin resistance. CLINICAL TRIALS REGISTRY NUMBER: NCT0152806.

8.
J Ren Nutr ; 24(1): 13-9, 19e1, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24355818

RESUMEN

OBJECTIVE: Phosphorus-based food additives increase the total phosphorus content of processed foods. However, the extent to which these additives augment total phosphorus intake per day is unclear. DESIGN AND METHODS: To examine the contribution of phosphorus-based food additives to the total phosphorus content of processed foods, separate 4-day menus for a low-additive and additive-enhanced diet were developed using Nutrition Data System for Research (NDSR) software. The low-additive diet was designed to conform to U.S. Department of Agriculture guidelines for energy and phosphorus intake (∼2,000 kcal/day and 900 mg of phosphorus per day), and it contained minimally processed foods. The additive-enhanced diet contained the same food items as the low-additive diet except that highly processed foods were substituted for minimally processed foods. Food items from both diets were collected, blended, and sent for measurement of energy and nutrient intake. RESULTS: The low-additive and additive-enhanced diet provided approximately 2,200 kcal, 700 mg of calcium, and 3,000 mg of potassium per day on average. Measured sodium and phosphorus content standardized per 100 mg of food was higher each day of the additive-enhanced diet as compared with the low-additive diet. When averaged over the 4 menu days, the measured phosphorus and sodium contents of the additive-enhanced diet were 606 ± 125 and 1,329 ± 642 mg higher than the low-additive diet, respectively, representing a 60% increase in total phosphorus and sodium content on average. When comparing the measured values of the additive-enhanced diet to NDSR-estimated values, there were no statistically significant differences in measured versus estimated phosphorus contents. CONCLUSION: Phosphorus and sodium additives in processed foods can substantially augment phosphorus and sodium intake, even in relatively healthy diets. Current dietary software may provide reasonable estimates of the phosphorus content in processed foods.


Asunto(s)
Dieta , Aditivos Alimentarios/análisis , Manipulación de Alimentos , Fósforo Dietético/análisis , Sodio en la Dieta/análisis , Calcio de la Dieta/análisis , Ingestión de Energía , Valor Nutritivo
9.
Obesity (Silver Spring) ; 20(5): 939-44, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22173571

RESUMEN

Among postmenopausal women, declining estrogen may facilitate fat partitioning from the periphery to the intra-abdominal space. Furthermore, it has been suggested that excess androgens contribute to a central fat distribution pattern in women. The objective of this longitudinal study was to identify independent associations of the hormone milieu with fat distribution in postmenopausal women. Fifty-three healthy postmenopausal women, either using or not using hormone replacement therapy (HRT) were evaluated at baseline and 2 years. The main outcomes were intra-abdominal adipose tissue (IAAT), subcutaneous abdominal adipose tissue, and total thigh fat analyzed by computed tomography scanning and leg fat and total body fat mass measured by dual-energy X-ray absorptiometry. Serum estradiol, estrone, estrone sulfate, total testosterone, free testosterone, androstenedione, dehydroepiandrosterone sulfate), sex hormone-binding globulin (SHBG), and cortisol were assessed. On average, in all women combined, IAAT increased by 10% (10.5 cm(2)) over 2 years (P < 0.05). Among HRT users, estradiol was inversely associated with, and estrone was positively associated with, 2-year gain in IAAT. Among HRT nonusers, free testosterone was inversely associated with, and SHBG was positively associated with, 2-year gain in IAAT. These results suggest that in postmenopausal women using HRT, greater circulating estradiol may play an integral role in limiting lipid deposition to the intra-abdominal cavity, a depot associated with metabolically detrimental attributes. However, a high proportion of weak estrogens may promote fat partitioning to the intra-abdominal cavity over time. Furthermore, among postmenopausal women not using HRT, greater circulating free testosterone may limit IAAT accrual.


Asunto(s)
Distribución de la Grasa Corporal , Estradiol/sangre , Estrona/sangre , Grasa Intraabdominal/metabolismo , Posmenopausia , Globulina de Unión a Hormona Sexual/metabolismo , Testosterona/sangre , Absorciometría de Fotón , Envejecimiento , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Resistencia a la Insulina , Grasa Intraabdominal/fisiología , Estudios Longitudinales , Persona de Mediana Edad , Posmenopausia/sangre
10.
Am J Obstet Gynecol ; 203(2): 153.e1-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20435291

RESUMEN

OBJECTIVE: We sought to determine the effect of daily soy supplementation on abdominal fat, glucose metabolism, and circulating inflammatory markers and adipokines in obese, postmenopausal Caucasian and African American women. STUDY DESIGN: In a double-blinded controlled trial, 39 postmenopausal women were randomized to soy supplementation or to a casein placebo without isoflavones. In all, 33 completed the study and were analyzed. At baseline and at 3 months, glucose disposal and insulin secretion were measured using hyperglycemic clamps, body composition and body fat distribution were measured by computed tomographic scan and dual energy x-ray absorptiometry, and serum levels of C-reactive protein, interleukin-6, tumor necrosis factor-alpha, leptin, and adiponectin were measured by immunoassay. RESULTS: Soy supplementation reduced total and subcutaneous abdominal fat and interleukin-6. No difference between groups was noted for glucose metabolism, C-reactive protein, tumor necrosis factor-alpha, leptin, or adiponectin. CONCLUSION: Soy supplementation reduced abdominal fat in obese postmenopausal women. Caucasians primarily lost subcutaneous and total abdominal fat, and African Americans primarily lost total body fat.


Asunto(s)
Citocinas/metabolismo , Suplementos Dietéticos , Posmenopausia/efectos de los fármacos , Proteínas de Soja/administración & dosificación , Grasa Abdominal/efectos de los fármacos , Grasa Abdominal/metabolismo , Absorciometría de Fotón , Adipoquinas/metabolismo , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Negro o Afroamericano/estadística & datos numéricos , Biomarcadores/análisis , Biomarcadores/metabolismo , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Composición Corporal/efectos de los fármacos , Índice de Masa Corporal , Proteína C-Reactiva/efectos de los fármacos , Proteína C-Reactiva/metabolismo , Citocinas/efectos de los fármacos , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Inmunoensayo , Interleucina-6/metabolismo , Persona de Mediana Edad , Obesidad/tratamiento farmacológico , Obesidad/etnología , Obesidad/fisiopatología , Posmenopausia/etnología , Probabilidad , Valores de Referencia , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Población Blanca
11.
Nutr Metab (Lond) ; 7: 28, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20398267

RESUMEN

BACKGROUND: The prevalence of type 2 diabetes is higher among African Americans (AA) vs European Americans (EA), independent of obesity and other known confounders. Although the reason for this disparity is not known, it is possible that relatively low levels of vitamin D among AA may contribute, as vitamin D has been positively associated with insulin sensitivity in some studies. The objective of this study was to test the hypothesis that dietary vitamin D would be associated with a robust measure of insulin sensitivity in AA and EA women. METHODS: Subjects were 115 African American (AA) and 137 European American (EA) healthy, premenopausal women. Dietary intake was determined with 4-day food records; the insulin sensitivity index (SI) with a frequently-sampled intravenous glucose tolerance test and minimal modeling; the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) with fasting insulin and glucose; and body composition with dual-energy X-ray absorptiometry. RESULTS: Vitamin D intake was positively associated with SI (standardized beta = 0.18, P = 0.05) and inversely associated with HOMA-IR (standardized beta = -0.26, P = 0.007) in AA, and the relationships were independent of age, total body fat, energy intake, and % kcal from fat. Vitamin D intake was not significantly associated with indices of insulin sensitivity/resistance in EA (standardized beta = 0.03, P = 0.74 and standardized beta = 0.02, P = 0.85 for SI and HOMA-IR, respectively). Similar to vitamin D, dietary calcium was associated with SI and HOMA-IR among AA but not EA. CONCLUSIONS: This study provides novel findings that dietary vitamin D and calcium were independently associated with insulin sensitivity in AA, but not EA. Promotion of these nutrients in the diet may reduce health disparities in type 2 diabetes risk among AA, although longitudinal and intervention studies are required.

12.
Obesity (Silver Spring) ; 18(11): 2101-4, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20203630

RESUMEN

Calcium intake is reported to enhance weight loss with a preferential loss in trunk fat. Discrepant findings exist as to the effects of calcium intake on longitudinal changes in total fat mass and central fat deposition. Therefore, the purpose of this study was to determine associations between dietary calcium intake and 1-year change in body composition and fat distribution, specifically intra-abdominal adipose tissue (IAAT). A total of 119 healthy, premenopausal women were evaluated at baseline and 1 year later. Average dietary calcium was determined via 4-day food records. Total fat was determined by dual-energy X-ray absorptiometry (DXA) and subcutaneous abdominal adipose tissue (SAAT) and IAAT by computed tomography. Over the study period, participants' reported daily calcium and energy intakes were 610.0 ± 229.9 mg and 1,623.1 ± 348.5 kcal, respectively. The mean change in weight, total fat, IAAT, and SAAT was 4.9 ± 4.4 kg, 5.3 ± 4.0 kg, 7.7 ± 19.5 cm(2), and 49.3 ± 81.1 cm(2), respectively. Average calcium intake was significantly, inversely associated with 1-year change in IAAT (standardized ß: -0.23, P < 0.05) after adjusting for confounding variables. For every 100 mg/day of calcium consumed, gain in IAAT was reduced by 2.7 cm(2). No significant associations were observed for average calcium intake with change in weight, total fat, or SAAT. In conclusion, dietary calcium intake was significantly associated with less gain in IAAT over 1 year in premenopausal women. Further investigation is needed to verify these findings and determine the calcium intake needed to exert beneficial effects on fat distribution.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Distribución de la Grasa Corporal , Calcio de la Dieta/farmacología , Grasa Intraabdominal/efectos de los fármacos , Grasa Subcutánea Abdominal/efectos de los fármacos , Aumento de Peso/efectos de los fármacos , Absorciometría de Fotón , Adulto , Registros de Dieta , Ingestión de Energía , Femenino , Humanos , Grasa Intraabdominal/diagnóstico por imagen , Estudios Longitudinales , Premenopausia , Grasa Subcutánea Abdominal/diagnóstico por imagen , Adulto Joven
13.
Open Obes J ; 2: 137-144, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22039395

RESUMEN

Intramyocellular lipid (IMCL) has been inversely associated with insulin sensitivity in some, but not all, studies. This study utilized fast, high-resolution, magnetic resonance spectroscopic imaging (MRSI) to: investigate relationships between muscle lipids (IMCL and extramyocellular lipid (EMCL)) and insulin sensitivity in muscles of varying oxidative capacity, explore ethnic differences in these relationships, and determine whether a eucaloric, low-fat dietary intervention would reduce IMCL and increase insulin sensitivity. Subjects were 30 healthy, African-American (AA; n=14) and European-American (EA; n=16) males, BMI 26.49 (±5.57) kg/m(2), age 21.80 (±7.84) yrs. Soleus and tibialis anterior muscle lipids were quantified using MRSI. Insulin sensitivity was assessed via intravenous glucose tolerance test. A 2-week, eucaloric, low-fat diet intervention was conducted in a sub-group (n=12) subjects with assessments at baseline and post-intervention. Neither IMCL nor EMCL levels differed between ethnicities. In the total group, and within EA (but not AA), both tibialis anterior IMCL and EMCL were inversely associated with insulin sensitivity (P<0.05 for both); soleus muscle lipids were not associated with insulin sensitivity. Soleus, but not tibialis anterior, IMCL declined in both ethnic groups (average 25.3%; p<0.01) following dietary intervention; insulin sensitivity was unchanged. Results suggest that an association of muscle lipids with insulin sensitivity may be influenced by the oxidative capacity of the muscle group studied and may vary with ethnicity.

14.
Obesity (Silver Spring) ; 18(2): 247-53, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19680231

RESUMEN

Ethnic differences in insulin secretion and action between African Americans (AAs) and European Americans (EAs) may influence mobilization of free fatty acids (FFAs). We tested the hypotheses that FFA concentrations would be associated with measures of insulin secretion and action before and during a glucose challenge test. Subjects were 48 prepubertal girls, 60 premenopausal women, and 46 postmenopausal women. Fasting insulin (insulin(0)), the acute insulin response to glucose (AIR(g)), the insulin sensitivity index (S(I)), basal and nadir FFA (FFA(0), FFA(nadir)), and nadir time (TIME(nadir)) were determined during an intravenous glucose tolerance test (IVGTT). Stepwise multiple linear regression (MLR) analysis was conducted to identify associations of FFA(0), FFA(nadir), and TIME(nadir) with ethnicity, age group, insulin measures, indexes of body composition from dual-energy X-ray absorptiometry, and measures of fat distribution from computed tomography scan. In this population, insulin(0) and AIR(g) were higher among AAs vs. EAs, whereas S(I) was lower, independent of age group. MLR analyses indicated that FFA(0) was best predicted by lean tissue mass (LTM), leg fat mass, ethnicity (lower in AAs), S(I), and insulin(0). FFA(nadir) was best predicted by FFA(0), age group, and intra-abdominal adipose tissue (IAAT). TIME(nadir) was best predicted by leg fat mass, AIR(g), and S(I). In conclusion, indexes of insulin secretion and action were associated with FFA dynamics in healthy girls and women. Lower FFA(0) among AAs was independent of insulin(0) and S(I). Whether lower FFA(0) is associated with substrate oxidation or risk for obesity remains to be determined.


Asunto(s)
Adiposidad/etnología , Negro o Afroamericano , Ácidos Grasos no Esterificados/sangre , Resistencia a la Insulina/etnología , Insulina/sangre , Obesidad/etnología , Población Blanca , Absorciometría de Fotón , Adolescente , Adulto , Factores de Edad , Anciano , Envejecimiento/etnología , Envejecimiento/metabolismo , Niño , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Modelos Lineales , Persona de Mediana Edad , Obesidad/metabolismo , Obesidad/fisiopatología , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Estados Unidos , Adulto Joven
15.
J Nutr ; 139(4): 680-3, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19297430

RESUMEN

Baseline serum C-reactive protein (CRP) concentrations play a role in the lipid response to diet. This study was a randomized, cross-over, controlled feeding study with 3 phases of 25 d each aimed at determining whether baseline CRP concentrations modulate the serum lipid response to diets differing in fat type and quantity. Participants were adult men and women, age 19-65 y, with LDL-cholesterol concentrations of 3.37-4.66 mmol/L. All participants consumed 3 diets differing in the type of snack, either low or high in fat: low-fat (30.8% of energy), moderate in fat and saturated fat (37.9 and 11.4% of energy, respectively), or moderate in fat and polyunsaturated fat (36.3 and 9.7% of energy, respectively). Using baseline CRP as a continuous variable, CRP x diet interactions on change in serum lipoprotein_a (P = 0.045) and HDL-cholesterol (P = 0.06) were observed. When we used previously established categories to define CRP concentrations (low, <1 mg/L; intermediate, 1-3 mg/L; or high, >3 mg/L), we found a CRP x diet interaction on change in triglyceride concentrations (P = 0.03) and trends for CRP x diet interaction on change in LDL (P = 0.06) and total cholesterol (P = 0.07). If replicated, these results suggest that considering baseline CRP concentrations when prescribing dietary interventions to lower lipid concentrations may be useful. Individuals with high baseline CRP concentrations may benefit from moderate-fat, high polyunsaturated fat diets, whereas those with low baseline CRP concentrations may obtain greater lipid-lowering benefits from low-fat diets.


Asunto(s)
Proteína C-Reactiva/metabolismo , Dieta con Restricción de Grasas , Metabolismo de los Lípidos/efectos de los fármacos , Adulto , Anciano , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Am J Clin Nutr ; 89(4): 1138-44, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19211818

RESUMEN

BACKGROUND: Overweight children have greater circulating concentrations of markers of inflammation (MOI) than do lean children. Whether adiposity influences the postprandial MOI response is unknown. OBJECTIVE: We aimed to evaluate the relations of fasting and postprandial MOI with total and regional adiposity and insulin sensitivity in children. DESIGN: Fifty-nine children aged 7-12 y were assessed for C-reactive protein (CRP), interleukin-6 (IL-6), and soluble tumor necrosis factor receptor-2 (sTNF-R2) in the fasted state and after a mixed meal. Insulin sensitivity, body composition, and abdominal adipose tissue distribution were assessed with a frequently sampled intravenous-glucose-tolerance test, dual-energy X-ray absorptiometry, and computed tomography, respectively. RESULTS: Central adipose measures were not independently associated with fasting MOI, although they were independently inversely associated with the postprandial sTNF-R2 response (r = -0.30 to -0.37, P = 0.02-0.006). The inverse association between intraabdominal adipose tissue and the postprandial CRP response was nearly significant (r = -0.27, P = 0.05). Insulin sensitivity was not associated with fasting or postprandial CRP or sTNF-R2; however, there was a positive relation between insulin sensitivity and fasting IL-6 (r = 0.27, P = 0.03), which was attenuated after adjustment for lean body mass (r = 0.25, P = 0.08). CONCLUSIONS: Excess adiposity is associated with both fasting and postprandial MOI. The postprandial MOI response may be influenced by central adiposity in children. The positive association of insulin sensitivity with IL-6 warrants further study.


Asunto(s)
Grasa Abdominal/metabolismo , Proteína C-Reactiva/metabolismo , Inflamación/sangre , Interleucina-6/sangre , Sobrepeso/sangre , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Delgadez/sangre , Biomarcadores/sangre , Composición Corporal , Niño , Estudios Transversales , Ayuno/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Masculino , Periodo Posprandial
17.
Diabetes Care ; 32(1): 9-13, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18840771

RESUMEN

OBJECTIVE: The aim of this study was to examine the association of physical activity with glucose tolerance and resting energy expenditure (REE) among adolescents. RESEARCH DESIGN AND METHODS: Subjects were 32 male and female adolescents aged 12-18 years. Intravenous glucose tolerance (K(g)) and REE were assessed under inpatient conditions after an overnight fast. K(g) was determined as the inverse slope of time versus (ln) glucose over minutes 8-19 of an intravenous glucose tolerance test. Physical activity was assessed over 8 days using accelerometry (counts per minute). RESULTS: In multiple linear regression analysis, K(g) was positively associated with total physical activity (TPA), moderate physical activity (MPA), and 5-min bouts of MPA. Similarly, REE was positively associated with TPA, MPA, and 5-min bouts of MPA. CONCLUSIONS: In this population, physical activity was positively related to both glucose tolerance and REE. These results suggest that moderate activity may be beneficial in the prevention of diabetes in adolescent populations both through promoting efficient glucose disposal and through increasing energy expenditure.


Asunto(s)
Diabetes Mellitus Tipo 2/prevención & control , Metabolismo Energético , Ejercicio Físico , Tejido Adiposo/anatomía & histología , Adolescente , Metabolismo Basal , Población Negra , Composición Corporal , Niño , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Estilo de Vida , Estudios Longitudinales , Masculino , Análisis de Regresión , Descanso/fisiología , Factores de Riesgo , Caracteres Sexuales , Población Blanca
18.
J Am Coll Nutr ; 27(5): 547-52, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18845704

RESUMEN

OBJECTIVE: Medium chain triglyceride (MCT) consumption may have a beneficial impact on weight management, however, some studies point to a negative impact of MCT oil consumption on cardiovascular disease risk. This study examined the effects of MCT oil consumption, as part of a weight loss diet, on metabolic risk profile compared to olive oil. DESIGN: Thirty-one men and women, age 19-50 y and body mass index 27-33 kg/m(2), completed this randomized, controlled, 16-week weight loss program. Oils were consumed at a level of approximately 12% of the subjects' prescribed energy intakes in the form of muffins and liquid oil. RESULTS: After controlling for body weight, there was a significant effect of time on fasting serum glucose (P = 0.0177) and total cholesterol (P = 0.0386) concentrations, and on diastolic blood pressure (P = 0.0413), with reductions in these variables occurring over time; there was no time-by-diet interaction for any of the parameters studied. Two of the 3 subjects in the MCT oil group with evidence of the metabolic syndrome at baseline did not have metabolic syndrome at endpoint. In the olive oil group, 6 subjects had the metabolic syndrome at baseline; 2 subjects no longer had metabolic syndrome at endpoint, 1 person developed metabolic syndrome, and 4 subjects did not have any change in their metabolic syndrome status. CONCLUSIONS: Our results suggest that MCT oil can be incorporated into a weight loss program without fear of adversely affecting metabolic risk factors. Distinction should be made regarding chain length when it comes to discussing the effects of saturated fats on metabolic risk factors.


Asunto(s)
Dieta Reductora , Ácidos Grasos/administración & dosificación , Síndrome Metabólico/etiología , Sobrepeso/dietoterapia , Aceites de Plantas/administración & dosificación , Triglicéridos/administración & dosificación , Adulto , Glucemia , Presión Sanguínea , Ácidos Grasos/efectos adversos , Femenino , Humanos , Insulina , Masculino , Aceite de Oliva , Sobrepeso/complicaciones , Aceites de Plantas/efectos adversos , Grupos Raciales , Triglicéridos/efectos adversos , Pérdida de Peso
19.
Obesity (Silver Spring) ; 16(5): 1045-51, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18356845

RESUMEN

OBJECTIVE: To determine what effect diet-induced approximately 12 kg weight loss in combination with exercise training has on body composition and resting energy expenditure (REE) in premenopausal African-American (AA) and European-American (EA) women. METHODS AND PROCEDURES: This study was a longitudinal, randomized weight loss clinical intervention, with either aerobic (AT), resistance (RT), or no exercise training (NT). Forty-eight AA and forty-six EA premenopausal overweight (BMI between 27 and 30) women underwent weight loss to a BMI<25. Body composition (densitometry), REE (indirect calorimetry), maximal oxygen uptake (VO2max), and muscular strength (isometric elbow flexion) were evaluated when subjects were in energy balance. RESULTS: AA women lost less fat-free mass (FFM, P

Asunto(s)
Composición Corporal/fisiología , Dieta Reductora , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Obesidad/terapia , Descanso/fisiología , Pérdida de Peso/fisiología , Adulto , Negro o Afroamericano , Índice de Masa Corporal , Peso Corporal/fisiología , Terapia Combinada , Femenino , Humanos , Estudios Longitudinales , Fuerza Muscular/fisiología , Obesidad/etnología , Obesidad/fisiopatología , Consumo de Oxígeno/fisiología , Aptitud Física/fisiología , Población Blanca
20.
Obesity (Silver Spring) ; 16(4): 797-803, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18239569

RESUMEN

OBJECTIVE: We have recently reported that parous European-American (EA) women have disproportionately more intra-abdominal adipose tissue (IAAT) than their nulliparous counterparts. Mediating mechanisms for IAAT accumulation remain unknown; however, some evidence suggests a possible catecholamine link. The objective of this study was to determine whether the IAAT-parity relationship found in EA women exists in African-American (AA) women and to determine whether catecholamines play a mediating role. METHODS AND PROCEDURES: Subjects included 44 EA and 47 AA premenopausal women. Free-living physical activity by doubly labeled water (activity-related time equivalent (ARTE)), body composition (air plethysmography, computed tomography), and 24-h fractionated urinary catecholamines were measured. RESULTS: Repeated measures ANOVA revealed parous EA and AA women had significantly higher IAAT than their nulliparous counterparts (100.1 +/- 28.5 and 76.2 +/- 34.8 cm(2) vs. 75.9 +/- 29.1 and 59.6 +/- 15.0 cm(2)). In AA women and nulliparous women, 24-h urinary dopamine was significantly higher (AA parous 260.8 +/- 88; EA parous 197.2 +/- 78.8; AA nulliparous 376.5 +/- 81; EA nulliparous 289.6 +/- 62). Multiple regression analysis for modeling IAAT indicated that race, parity, dopamine, ARTE, and VO(2max) were all significant and independent contributors to the model (Unstandardized betas: race -32.6 +/- 7.4; parity (number of births) 10.0 +/- 3.4; 24-h urinary dopamine 0.08 +/- 0.04; ARTE (min/day) -0.09 +/- 0.04; VO(2max) (ml/kg/min) -2.8 +/- 1.0). DISCUSSION: Independent of the potential confounders: age, race, percent body fat, IAAT, 24-h fractionated urinary catecholamines, physical activity, and VO(2max), parous EA and AA women had more IAAT than their nulliparous counterparts. Of the catecholamines, dopamine was found to be significantly lower in parous women and higher in AA's. Dopamine, however, did not explain racial or parity differences in IAAT.


Asunto(s)
Grasa Abdominal/anatomía & histología , Negro o Afroamericano , Catecolaminas/orina , Obesidad/etnología , Obesidad/metabolismo , Paridad , Población Blanca , Grasa Abdominal/metabolismo , Adulto , Dopamina/orina , Epinefrina/orina , Femenino , Humanos , Persona de Mediana Edad , Actividad Motora , Norepinefrina/orina , Obesidad/patología , Consumo de Oxígeno , Aptitud Física , Embarazo , Premenopausia/etnología , Premenopausia/metabolismo , Análisis de Regresión , Factores de Riesgo , Estados Unidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...