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BACKGROUND: Metabolic state (fed vs fasted) can result in marked differences in exercise metabolism, fat, and carbohydrate oxidation. In addition, a large inter-individual range in metabolic response to sitting and standing when fasted has been observed. Here, we examined the effect of metabolic state on the energy cost of posture allocation. METHODS: Thirty male participants were recruited and followed a 1 h sit-stand protocol in a fasted and fed state inside a whole body calorimeter to measure energy expenditure (EE) and respiratory quotient (RQ). Body composition and resting metabolic rate were measured before the start. Fasted EE response was used to phenotype participants as energy savers (≤5% ΔEE from sitting to standing) or energy spenders (>5% ΔEE). RESULTS: In a fasted state, ΔEE from sitting to standing in energy spenders was 10.2 ± 2.7% compared to 2.6 ± 1.9% in energy savers (p < 0.001). Postprandial, there was no difference in ΔEE between energy spenders and energy savers (10.8 ± 5.1% vs 9.4 ± 5.7%). In a fasted state, significant correlations were observed between body fat (%) and ΔEE (%) (R2 = 0.55, p < 0.001), body fat (%) and ΔRQ (R2 = 0.28, p < 0.001) and ΔEE (%) and ΔRQ (R2 = 0.43, p < 0.001); these correlations were not present after the meal. CONCLUSIONS: The current study showed for the first time, that the observed difference between energy spenders and energy savers in a fasted state, disappeared after the consumption of a meal. Therefore, metabolic state may be important to consider when assessing metabolic phenotypes. Differences in body composition were observed between the energy spender and energy saver phenotype. The current findings may have implications on health and weight management recommendations on posture to increase non-exercise activity thermogenesis. This trial was retrospectively registered on 19 December 2017 as NCT03378115 on Clinicaltrials.gov .
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Metabolismo Energético , Postura , Calorimetria , Calorimetria Indireta , Metabolismo Energético/fisiologia , Humanos , Masculino , Fenótipo , Postura/fisiologiaRESUMO
The role of micronutrients such as folate and vitamin B-12 in bone quality has been widely studied with conflicting results. Ethnicity seems to play a large role on nutrient intake, as diet varies across cultures. In this study, we examined the relationships of BMD, proximal femur strength, and bone resorption with plasma folate and vitamin B-12 in a cohort of 93 healthy postmenopausal women of Chinese-Singaporean descent. The parameters examined were areal (aBMD) and volumetric BMD (vBMD) of the proximal femur and the third lumbar vertebra (L3), total body aBMD, proximal femur bending, compressive and impact strength indices (composite strength indices) and circulating levels of C-telopeptide of type I collagen. Eighteen participants (19.4%) had aBMD in the osteoporotic range (osteoporosis group), 59 (63.4%) in the osteopenic range (osteopenia group), and the remaining 16 (17.2%) in the normal range (normal BMD group). Circulating folate levels were significantly higher in the normal BMD group compared with the osteoporosis group. Using linear regression analysis, we found that overall, aBMD and vBMD are positively associated with folate concentrations, whereas composite strength indices were positively associated with vitamin B-12 concentrations. These findings support the existing literature and suggest a link between levels of circulating folate/vitamin B-12 and BMD/bone strength in the cohort examined. Further investigation is needed to examine if individuals with inadequate circulating levels of these nutrients could decrease their risk for fragility fractures through better nutrition or vitamin supplementation. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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OBJECTIVES: The first aim of this study was to determine the metabolic type of individuals based on the postprandial metabolic response after the ingestion of a meal challenge that was high protein and either high glucose (high GI) or fructose (low GI). The second aim was to compare the baseline characteristics between the different metabolic types (metabotypes). The third aim was to assess whether the inclusion of fructose or glucose in a high-protein breakfast modulated the glucose, insulin, and TG response over a 4-h period. METHODS: The study included 46 Asian women with a body mass index between 17 and 28 kg/m2 in a randomized crossover design. Metabolic typing was based on the assessment of the postprandial glycemic, insulin and triacylglycerol (TG) response after the ingestion of two high-protein meal challenges either high in fructose or glucose. Baseline characteristics were compared between the different metabolic types. Baseline and 4-h postprandial blood samples were collected and glucose, insulin, and TG levels were analyzed. Cluster analysis was used to phenotype the participants in distinct groups. Baseline characteristics including anthropometry, glycemic, and lipid profiles and resting metabolic rate were compared among the metabolic types. RESULTS: Cluster analysis revealed that women could be grouped into three metabolic types based on postprandial glucose, insulin, and TG response after the fructose meal challenge: cluster 1 with an average glucose + high TG response (highTG; n = 12), cluster 2 with a high glucose + average TG response (highGLU; n = 8), and cluster 3 with an average glucose + average TG response (Avg; n = 26). Post hoc analysis revealed significantly greater waist-to-hip ratio and a worse lipid profile for the highTG cluster and a higher fasting blood glucose, body mass index, fat percentage, and hip circumference in the highGLU cluster. CONCLUSIONS: Three metabolic types with a distinct metabolic response could be distinguished after a high fructose meal. The results suggest a different risk profile and may indicate why some people develop diabetes in an obesogenic environment. Improved metabolic-type assessments will enable us to develop and optimize nutritional and medical interventions for individuals with differing diabetes risk.
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Refeições , Período Pós-Prandial , Glicemia , Estudos Cross-Over , Feminino , Frutose , Humanos , Insulina , TriglicerídeosRESUMO
OBJECTIVES: Fructose is often recommended due to its ability to lower glycemic response and its increased thermogenic effect. Additionally, proteins can reduce the glycemic response of carbohydrate-rich foods and have a high diet-induced thermogenesis (DIT). The aim of this study was to investigate whether the inclusion of fructose in a high-protein meal would demonstrate metabolic advantages. METHODS: Nineteen Asian women (body mass index 17-28 kg/m2) consumed a low-glycemic index (GI; fructose) or high GI (glucose), high-protein breakfast followed by a standardized lunch in a randomized crossover design. Simultaneously, 8-h continuous glucose monitoring provided incremental area under the curve (iAUC) and 4-h indirect calorimetry provided DIT and respiratory quotient (RQ). RESULTS: The low GI diet resulted in a lower glucose iAUC (135 ± 25 versus 212 ± 23 mmol/L, P < 0.05) following breakfast, but no second-meal effect after the standardized lunch (217 ± 37 versus 228 ± 27 mmol/L, P < 0.05) compared with the high GI diet. Furthermore, 4-h DIT was greater (40.6 ± 2.3 versus 34.9 ± 1.8 kcal, P < 0.05) and RQ was increased after the fructose high-protein breakfast (0.047 ± 0.009 versus 0.028 ± 0.009, P < 0.05) compared with the glucose meal. CONCLUSIONS: Fructose is an effective sweetener in reducing glycemia and increasing DIT in the presence of a high-protein diet. However, the reduced fat oxidation after high fructose consumption might present a risk for increased lipogenesis.
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Dieta Rica em Proteínas/métodos , Frutose/administração & dosagem , Índice Glicêmico , Metabolismo dos Lipídeos , Termogênese , Adulto , Idoso , Estudos Cross-Over , Feminino , Humanos , Refeições , Pessoa de Meia-Idade , Oxirredução , Valores de Referência , Adulto JovemRESUMO
Insulin resistance (IR) is accompanied by increased areal or volumetric bone mineral density (aBMD or vBMD), but also higher fracture risk. Meanwhile, imbalances in bone health biomarkers affect insulin production. This study investigates the effect of IR on proximal femur and lumbar spine BMD, femoral neck bending, compressive and impact strength indices (Composite Strength Indices) and circulating levels of parathyroid hormone (PTH), C-telopeptide of Type I collagen (CTx-1) and 25(OH) Vitamin D3, in a cohort of 97 healthy, non-obese, menopausal Chinese-Singaporean women. Lumbar spine aBMD was inversely associated with IR and dependent on lean body mass (LBM) and age. No such associations were found for vBMD of the third lumbar vertebra, aBMD and vBMD of the proximal femur, or circulating levels of PTH, CTx-1 and 25(OH) Vitamin D3. Composite Strength Indices were inversely associated with IR and independent of LBM, but after adjusting for fat mass and age, this association remained valid only for the impact strength index. Composite Strength Indices were significantly lower in participants with a high degree of IR. Our findings on IR and Composite Strength Indices relationships were in agreement with previous studies on different cohorts, but those on IR and BMD associations were not.