Comparison of aspartame- and sugar-sweetened soft drinks on postprandial metabolism

Aim: We compared the impact of artificially- and sugar-sweetened beverages co-ingested with a mixed meal on postprandial fat and carbohydrate oxidation, blood glucose, and plasma insulin and triglyceride concentrations. Methods: Eight college-aged, healthy males completed three randomly assigned trials, which consisted of a mixed macronutrient meal test with 20oz of Diet-Coke (AS), Coca-Cola (NS), or water (CON). One week separated each trial and each participant served as his own control. Resting energy expenditure (REE) via indirect calorimetry, blood pressure, and blood samples were obtained immediately before, 5, 10, 30, 60, 120, and 180 min after meal and beverage ingestion. A two-way (treatment × time) repeated-measures ANOVA was conducted to assess REE, fat and carbohydrate oxidation rates, blood glucose, and plasma insulin and triglyceride concentrations. Results: There was a significant main effect of treatment on total fat oxidation (P = 0.006), fat oxidation was significantly higher after AS (P = 0.006) and CON (P = 0.001) compared to following NS. There was a significant main effect of treatment on total carbohydrate oxidation (P = 0.005), carbohydrate oxidation was significantly lower after AS (P = 0.014) and CON (P = 0.001) compared to following NS. Plasma insulin concentration AUC was significantly lower after AS (P = 0.019) and trended lower in CON (P = 0.054) compared to following NS. Conclusion: Ingestion of a mixed meal with an artificially-sweetened beverage does not impact postprandial metabolism, whereas a sugar-sweetened beverage suppresses fat oxidation and increases carbohydrate oxidation compared to artificially-sweetened beverage and water.

APOE ɛ4 Is Associated with Postprandial Inflammation in Older Adults with Metabolic Syndrome Traits

The apolipoprotein E (APOE) polymorphism impacts blood lipids and biomarkers of oxidation and inflammation, contributing to an isoform-dependent disease risk. We investigated the effect of the APOE genotype on postprandial metabolism after consumption of three different isoenergetic (4200 kJ) meals in older adults with a CVD risk phenotype. In a randomized crossover study, participants with metabolic syndrome traits (APOE E3, n = 39; E4, n = 10; mean age, 70 ± 5 years; BMI 31.3 ± 3.0 kg/m2) consumed a Western-like diet high-fat (WDHF), Western-like diet high-carbohydrate (WDHC), or Mediterranean-like diet (MED) meal. Parameters of lipid and glucose metabolism, inflammatory, and oxidative parameters were analyzed in blood samples collected at fasting and 1–5 h postprandially. Data were analyzed by linear mixed models. The magnitude of the IL-6 increase after the WDHF meal was significantly higher in E4 than in E3 carriers (iAUC: E4 = 7.76 vs. E3 = 2.81 pg/mL × h). The time to detect the IL-6 increase was shorter in the E4 group. All meals produced postprandial glycemia, insulinemia, and lipidemia, without differences between the E3 and the E4 groups. IL-1β and oxidized LDL levels did not change postprandially. In conclusion, APOE E4 carriers display increased postprandial inflammation, indicated by higher postprandial IL-6 increase, when compared to non-carriers.

Acute Metabolic Response in Adults to Toddler Milk Formulas with Alternating Higher and Lower Protein and Fat Contents, a Randomized Cross-Over Trial

Protein intake in early life influences metabolism, weight gain, and later obesity risk. As such, a better understanding of the effects of protein intake on the postprandial metabolism and its dynamics over time may elucidate underlying mechanisms. In a randomized crossover study, we observed fasted adults who consumed two isocaloric toddler milk formulas concentrated as meals of 480 kcal with 67 g of carbohydrates 30 g (HP) or 7 g (LP) protein, and 10 g or 20 g fat, respectively. Anthropometry and body plethysmography were assessed, and blood samples collected at baseline and over five hours. Time-specific concentrations, areas under concentration curves (AUC), and maximum values of metabolites were compared by paired t-tests to examine the effects of protein content of toddler milks on postprandial plasma concentrations of insulin, glucose, branched-chain amino acids (BCAA), urea and triglycerides. Twenty-seven men and women aged 26.7 ± 5.0 years (BMI: 22.2 ± 2.5 kg/m2) (mean ± SD) participated. BCAA AUC, and Cmax values were significantly higher with HP than LP (144,765 ± 21,221 vs. 97,089 ± 14,650 µmol min/L, p < 0.001; 656 ± 120 vs. 407 ± 66 µmol/L, p < 0.001), as were insulin AUC and Cmax values (6674 ± 3013 vs. 5600 ± 2423 µmol min/L, p = 0.005; 71 ± 37 vs. 55 ± 28 µmol /L, p = 0.001). Higher glucose, urea, and triglyceride concentrations occurred in the late postprandial phase (≥180 min) with HP. In conclusion, we noted that higher milk protein intake induces increased postprandial BCAA concentrations for at least 5 h and led to higher initial insulin secretion. Gluconeogenesis due to an influx of amino acids and their degradation after HP meal might explain the late effects of protein intake on glucose and insulin.

Postprandial Metabolism and Physical Activity in Asians: A Narrative Review

The widespread benefits of physical activity in enhancing health and lowering the risk of non-communicable chronic diseases are well established across populations globally. Nevertheless, the prevalence of several lifestyle-related chronic diseases, including cardiovascular disease, varies markedly across countries and ethnicities. Direct ethnic comparative studies on the health benefits of physical activity are sparse and evidence-based physical activity guidelines are not ethnicity-specific. Indeed, physical activity guidelines in some Asian countries were developed primarily based on data from Western populations even though the magnitude of potential benefit may not be the same among different ethnic groups. Unfavorable diurnal perturbations in postprandial triglycerides and glucose are risk factors for cardiovascular disease. This narrative review summarizes differences in these risk factors primarily between individuals of Asian and white European descent but also within different Asian groups. Moreover, the variable effects of physical activity on mitigating risk factors among these ethnic groups are highlighted along with the underlying metabolic and hormonal factors that potentially account for these differences. Future ethnic comparative studies should include investigations in understudied ethnic groups, such as those of East Asian origin, given that the effectiveness of physical activity for ameliorating cardiovascular disease varies even among Asian groups.

Effects of intermittent (5:2) or continuous energy restriction on basal and postprandial metabolism: a randomised study in normal-weight, young participants

Background/objectives Intermittent energy restriction (IER) may overcome poor long-term adherence with continuous energy restriction (CER), for weight reduction. We compared the effects of IER with CER for fasting and postprandial metabolism and appetite in metabolically healthy participants, in whom excess weight would not confound intrinsic metabolic differences. Subjects/methods In a 2-week randomised, parallel trial, 16 young, healthy-weight participants were assigned to either CER (20% below estimated energy requirements (EER)) or 5:2 IER (70% below EER on 2 non-consecutive days; 5 days at EER, per week). Metabolic and appetite regulation markers were assessed before and for 3 h after a liquid breakfast; followed by an ad libitum lunch; pre- and post-intervention. Results Weight loss was similar in both groups: −2.5 (95% CI, −3.4, −1.6) kg for 5:2 IER vs. −2.3 (−2.9, −1.7) kg for CER. There were no differences between groups for postprandial incremental area under the curve for serum insulin, blood glucose or subjective appetite ratings. Compared with CER, 5:2 IER led to a reduction in fasting blood glucose concentrations (treatment-by-time interaction, P = 0.018, η2p = 0.14). Similarly, compared with CER, there were beneficial changes in fasting composite appetite scores after 5:2 IER (treatment-by-time interaction, P = 0.0003, η2p = 0.35). Conclusions There were no significant differences in postprandial insulinaemic, glycaemic or appetite responses between treatments. However, 5:2 IER resulted in greater improvements in fasting blood glucose, and beneficial changes in fasting subjective appetite ratings.

Frequency of Interruptions to Sitting Time: Benefits for Postprandial Metabolism in Type 2 Diabetes

<b>Purpose:</b> To determine whether interrupting sitting with brief bouts of simple resistance activities (SRAs) at different frequencies improves postprandial glucose, insulin and triglycerides in adults with medication-controlled type 2 diabetes (T2D). <p><b>Methods:</b> Participants [n=23, 10 females, Age: 62±8 y (mean±SD), BMI: 32.7 ± 3.5 kg^.m^-2] completed a three-armed randomized crossover trial (6-14 day washout): sitting uninterrupted for 7 h (SIT); sitting with 3-minute SRAs (half-squats, calf raises, gluteal contractions, and knee raises) every 30 minutes (SRA3); and, sitting with 6-minute SRAs every 60 minutes (SRA6). Net incremental areas under the curve (iAUC_net) for glucose, insulin, and triglycerides were compared between conditions.</p> <p><b>Results:</b> <a>Glucose and insulin 7 h iAUC_netwere attenuated significantly during SRA6 (glucose 17.0 mmol^.h^.L^-1, 95% CI 12.5, 21.4; insulin 1229 pmol^.h^.L^-1, 95% CI 982, 1538) when compared to SIT (glucose 21.4 mmol^.h^.L^-1, 95% CI 16.9, 25.8; insulin 1411 pmol^.h^.L^-1, 95% CI 1128, 1767; <i>P</i> < 0.05), and compared to SRA3 ( for glucose only; 22.1 mmol^.h^.L^-1, 95% CI 17.7, 26.6; <i>P </i>= 0.01) No significant differences in glucose or insulin iAUC_net were observed comparing SRA3 and SIT. There was no statistically significant effect of condition on triglyceride iAUC_net. </a></p> <p><b>Conclusion:</b> In adults with medication-controlled T2D, interrupting prolonged sitting with 6-minute SRAs every 60 minutes reduced postprandial glucose and insulin responses. Other frequencies of interruptions and potential longer-term benefits require examination to clarify clinical relevance. </p>