Polycystic ovary syndrome (PCOS) is an insulin resistant state, compensated by hyperinsulinemia. More than 50% of the women with PCOS are obese, and/or have metabolic syndrome. Weight loss improves both metabolic and reproductive outcomes. Not only the energy content, but also the nutrient composition of a diet may be important. This article will present a series of studies from our research comparing effects of dietary protein vs. simple-carbohydrates (CHO). Results of the acute challenge studies demonstrate that simple-CHO intake causes reactive hypoglycemia in one third of the women with PCOS, especially among obese and insulin resistant individuals. Symptoms of hypoglycemia are associated with secretion of cortisol and adrenal androgens. Simple-CHO suppresses the hunger signal ghrelin for a shorter period. During weight loss, women who receive protein supplementation achieve larger amounts of weight- and fat-mass losses. Amino acid compositions of the protein supplements do not affect the improvements in weight and insulin resistance. It is plausible that simple-CHO intake leads to weight gain, or interferes with weight-loss, by causing reactive hypoglycemia, triggering adrenal steroid secretion, and leading to snacking. Since obese women with PCOS are more susceptible to reactive hypoglycemia, a vicious cycle establishes. Restriction of simple-CHO may break this cycle.

Twelve overnight fasted, healthy, male volunteers received on separate days a test breakfast consisting of (A) 100 g fresh white bread (providing 50 g starch) and 250 mL drinking water, (B) the same bread with a supplement of 10 g alpha-cyclodextrin dissolved in the drinking water (250 mL), and (C) 250 mL drinking water containing 25 g alpha-cyclodextrin. Capillary and venous blood samples were collected before breakfast and at regular intervals for a period of 3 hours thereafter. Plasma glucose was determined in capillary blood and plasma insulin in venous blood samples. Breakfast (A) let to the expected rise in blood glucose and insulin concentrations. Breakfast (C) did not produce a significant glycemic and insulinemic response, demonstrating that alpha-cyclodextrin is not hydrolyzed to glucose in the human digestive tract. Mild intestinal symptoms after the ingestion of alpha-cyclodextrin were reported by 4 subjects. The postprandial rises of plasma glucose and insulin were significantly smaller after breakfast (B) than (A). Under the conditions of this study, alpha-cyclodextrin reduced the glycemic and insulinemic index of white bread by 57 and 55 %, respectively. The postprandial time profile of plasma glucose and insulin suggests that, in an initial phase, the digestion of starch is inhibited by alpha-cyclodextrin almost completely. Yet, despite the delayed and reduced digestion of starch, the intake of breakfast (B) was not associated with flatulence or any other gastrointestinal symptoms.

Postprandial glucose levels between 4 and 7.9 hours (PPG4–7.9h) correlate with mortality from various diseases including hypertension, diabetes, cardiovascular disease, and cancer. This study aimed to assess if predicted PPG4–7.9h could diagnose diabetes. Two groups of participants were involved: Group 1 (4420 participants) had actual PPG4–7.9h, while Group 2 (8422 participants) lacked this measure but had all the diabetes diagnostic measures. Group 1 underwent multiple linear regression to predict PPG4–7.9h using 30 predictors, achieving accuracy within 11.1 mg/dL in 80% of the participants. Group 2 had PPG4–7.9h predicted using this model. Receiver operating characteristic curve analysis showed that predicted PPG4–7.9h could diagnose diabetes with an accuracy of 87.3% in Group 2, with a sensitivity of 75.1% and specificity of 84.1% at the optimal cutoff of 102.5 mg/dL. Simulation on 10,000 random samples from Group 2 revealed that 175 participants may be needed to investigate PPG4–7.9h as a diabetes diagnostic marker with a power of at least 80%. In conclusion, predicted PPG4–7.9h appears to be a promising diagnostic indicator for diabetes. Future studies seeking to ascertain its definitive diagnostic value might require a minimum sample size of 175 participants.

BACKGROUND This study investigated the association of postprandial plasma glucose (PPG) with cancer mortality using a general cohort of US adults. METHODS This cohort study included 14,860 US adults who attended the third National Health and Nutrition Examination Survey from 1988 to 1994, with mortality being followed up to December 31, 2019. The experimental exposures were levels of plasma glucose, including PPG with a fasting time of 0-3.9 h (PPG_0-3.9h) and 4-7.9 h (PPG_4-7.9h), plasma glucose with a fasting time ≥ 8 h (PG_fasting), and plasma glucose at 2 h after oral glucose tolerance test (PG_2hOGTT). Plasma glucose-associated cancer mortality risk was assessed using Cox proportional hazards models. RESULTS A 1-natural-log-unit increase in PPG_4-7.9h was associated with a higher multivariate-adjusted risk for cancer mortality [hazard ratio (HR), 3.24; 95% confidence interval (CI), 1.50-7.00]. However, PPG_0-3.9h, PG_fasting, PG_2hOGTT, hemoglobin A_1c, and insulin were not significantly associated with cancer mortality. The positive association of PPG_4-7.9h with cancer mortality remained in those without a prior diagnosis of cancer. CONCLUSIONS High PPG_4-7.9h is associated with a higher cancer mortality risk in US adults. Lowering PPG_4-7.9h may reduce cancer mortality.

Postprandial plasma glucose between 4 and 7.9 hours is associated with the diagnosis of diabetes, diabetes mortality, and cardiovascular mortality. However, it is unknown whether 2-hour plasma glucose during the oral glucose tolerance test conducted in this postprandial period (4–7.9 hours), termed as 2-h PGOGTT@4–7.9h, can accurately classify diabetes diagnosis and predict mortality risks. This study aimed to address these questions using 2,347 adult participants. Diabetes was defined as HbA1c ≥6.5%, and the ability of 2-h PGOGTT@4–7.9h to classify diabetes was analyzed using receiver operating characteristic curves. Cox proportional hazards models were employed to estimate mortality hazard ratios (HRs) and 95% confidence intervals (CIs). The results showed that 2-h PGOGTT@4–7.9h could classify diabetes with 92% accuracy. Participants were followed up for a mean of 21.4 years. A 1-natural-log higher 2-h PGOGTT@4–7.9h was associated with an increased risk of mortality from diabetes (adjusted HR, 21.1; 95% CI, 9.2–48.0) and cardiovascular disease (adjusted HR, 1.47; 95% CI, 1.13–1.91). Simulation analysis indicated that future studies may require at least 100 participants to investigate 2-h PGOGTT@4–7.9h for diabetes diagnosis. In conclusion, 2-h PGOGTT@4–7.9h may be useful for diabetes classification and prediction of mortality risk.

It is unknown whether postprandial plasma glucose measured from blood taken between 4 and 7.9 h (PPG4-7.9h) is associated with mortality from hypertension, diabetes, or cardiovascular disease (CVD). This study aimed to investigate these associations in 4,896 US adults who attended the third National Health and Nutrition Examination Survey. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of PPG4-7.9h for mortality. This cohort was followed up for 106,300 person-years (mean follow-up, 21.7 years). A 1-natural-log-unit increase in PPG4-7.9h was associated with a higher risk of mortality from hypertension (HR, 3.50; 95% CI, 2.34-5.24), diabetes (HR, 11.7; 95% CI, 6.85-20.0), and CVD (HR, 2.76; 95% CI, 2.08-3.68) after adjustment for all the tested confounders except hemoglobin A1c (HbA1c). After further adjustment for HbA1c, PPG4-7.9h remained positively associated with mortality from hypertension (HR, 2.15; 95% CI, 1.13-4.08) and CVD (HR, 1.62; 95% CI, 1.05-2.51), but was no longer associated with diabetes mortality. Subgroup analyses showed that similar results were obtained in the sub-cohort of participants without a prior diagnosis of myocardial infarction or stroke. In conclusion, PPG4-7.9h predicts mortality from hypertension and CVD independent of HbA1c.

An increase in plant-sourced (PS) nutrient intake is promoted in support of a sustainable diet. PS dietary minerals and proteins have bioactive properties that can affect bone health and the risk of fracture. In a group randomised, cross-over, design, this study evaluated the post-ingestion, temporal pattern of change in arterialised ionised calcium (iCa), parathyroid hormone (PTH), C-terminal crosslinked telopeptide of type I collagen (CTX) and procollagen type 1 amino-terminal propeptide (P1NP) for 4 hours following ingestion of a novel supplement (SUPP) containing a PS marine multi-mineral + PS protein isolate. A diurnally matched intake of mineral water was used as a control (CON). Compared to baseline, the change in iCa concentration was 0.022 (95%CI, 0.006 to 0.038, p = 0.011) mmol/l greater in SUPP than CON, resulting in a -4.214 (95%CI, -8.244 to -.183, p = 0.042) pg/mL mean reduction in PTH, a -0.64 (95%CI, -0.199 to -0.008, p = .029) ng/mL decrease in the biomarker of bone resorption, CTX, and no change in biomarker of bone formation, P1NP. Used as a dietary supplement, or by incorporation into a food matrix, the promotion of PS marine multi-mineral and PS protein isolates may contribute to a more sustainable diet and overall bone health.

The aim of this study was to investigate the relationship between postprandial glycemic levels based on flash-monitoring and the production of intestinal hydrogen (H2) and methane (CH4) gases based on measurement of the amount of these gases in exhaled air. We studied 14 subjects with type 2 diabetes mellitus (T2DM) and 10 individuals without diabetes (control) with 3 food-load tests with simultaneous determination of gases in exhaled air and assessment of glucose levels. In 15.4% of patients with T2DM, there was a non-significant increase in exhaled H2. How-ever, all subjects in the control group had significant increase in exhaled H2. Moreover, the level of H2 in exhaled breathafter food load in patients with T2DM was lower than in normoglycemic subjects. Also, in normoglycemic subjects there was an inverse correlation between maximum glucose rise and maximum H2 in exhaled air after food load. At the same time in patients with T2DM the level of CH4 in exhaled air directly correlated with the parameters of postprandial glycemia in the test with lactulose. Confirmation of a causal relationship between decreased H2 production, increased intestinal CH4 production, and more severe postprandial glycemia may identify new therapeutic targets in the correction of postprandial glycemia in patients with T2DM.

Background: The therapeutic benefits of fermented foods in the treatment and prevention of Type 2 diabetes mellitus have been reported. Aim: Inhibitory effect of fermented rice beverages on α-amylase, α-glucosidase and pancreatic lipase was evaluated. Method: Two fermented rice beverages-fermented rice alone (FKR) and fermented rice plus roasted peanuts (FKRG) were produced using spontaneous fermentation. Capacity of the beverages to inhibit al-pha-glucosidase, alpha-amylase and pancreatic lipase in vitro was evaluated and compared with standards (positive controls). Results: FKR exerted inhibition of α-glucosidase between 9.23-21.11% and FKRG 1.11-17.36% at the various concentrations respectively, with both samples showing the most significant inhibition (about 20%) at 125 μg/mL. FKRG exhibited greater alpha-amylase inhibition activity than FKR, but for both samples, the most significant (P < 0.05) inhibition occurred at 500 μg/mL. With pancreatic lipase, no significant inhibition was observed for both FKR and FKRG at the tested concentrations compared to Orlistat used as control; how-ever, at 31.25 μg /mL FKRG showed an inhibitory effect of approximately 15%, which was not evident at higher concentrations. Conclusion: Low to moderate inhibition of α-amylase, α-glucosidase and pancreatic lipase by both FKR and FKRG, showed that the fermented rice beverages have potential to modulate hyperglycemia in type 2 diabetes in vitro. This is an indi-cation that fermented rice beverage could prevent postprandial hyperglycemia in vivo.

Olive oil, as the main source of polyphenols in the Mediterranean diet pattern, is mentioned to show remarkable postprandial bioactivity, contributing to the reduction of cardiometabolic risk factors. In recent years, the consumption of refined olive oil, instead of other olive oil classes, led to a reduced intake of polyphenols from the usual diet. This controlled, human nutritional intervention inves-tigated whether the enhancement of refined olive oil with orange peel extract may modulate postprandial lipemia, glycemia and oxidative stress, in individuals at cardiometabolic risk. In a cross-over framework, 21 participants aged 30-65 years, who met the eligibility criteria, received a fat and carbohydrated meal of mashed potatoes, homogenized with refined olive oil (50 mL) or the functional olive oil, enhanced with 10% orange peel extract, intervening a washout week. Blood draws were performed in fasting, 30min, 1.5h and 3h after the meal intake. Plasma lipids, glucose, uric acid and total plasma antioxidant capacity according to FRAP method, were measured at each timepoint. A significant reduction of LDL-cholesterol was observed, 1.5 h and 3 h after the func-tional meal intake, compared to non-significant changes after the control meal (p <0.05). No other statistically significant interactions were detected to the remaining biomarkers (p> 0.05). Further investigation is needed for safer conclusions about the postprandial modulation of cardiometabolic risk factors, by the functional olive oil, enhanced with orange peel extract.

Postprandial hyperlipidemia showing postprandial increase in serum triglyceride (TG) is atherogenic and associated with the development of coronary artery disease (CAD). To diagnose postprandial hyperlipidemia, the oral fat loading test (OFLT) should be performed, however, this test is very time-consuming and is difficult to perform. Ele-vated serum TG levels reflect an increase in TG-rich lipoproteins (TRL) such chylomi-crons (CM), very low-density lipoproteins (VLDL) and their remnants (CM remnant [CMR] and VLDL remnant [VLDLR]). Understanding of elevation in CMR and/or VLDLR can lead us to understand the existence of postprandial hyperlipidemia. The measurements of apo B48 which is a constituent of CM and CMR, non-fasting TG which includes TG content in all lipoproteins including CM and CMR, non-high-density lipoprotein-cholesterol (non-HDL-C) which includes TRL and low-density lipoprotein, and remnant cholesterol, are useful to suspect the existence of postprandial hyperlipidemia. Postprandial hyperlipidemia is observed in patients with familial type III hyperlipoproteinemia, familial combined hyperlipidemia, chronic kidney disease, metabolic syndrome and type 2 diabetes. Postprandial hyperlipidemia is closely related to postprandial hyperglycemia, and insulin resistance may be an in-ducing and enhancing factor for both postprandial hyperlipidemia and postprandial hyperglycemia. Remnant lipoproteins and metabolic disorders associated with post-prandial hyperlipidemia have various atherogenic properties such as induction of in-flammation and endothelial dysfunction. A healthy diet, calorie restriction, weight loss and exercise, positively impact postprandial hyperlipidemia. Anti-hyperlipidemic drugs such pemafibrate, bezafibrate, ezetimibe and eicosapentaenoic acid have shown to improve postprandial hyperlipidemia. Anti-diabetic drugs including metformin, alpha-glucosidase inhibitors, pioglitazone, dipeptidyl-peptidase-4 inhibitors and glu-cagon like peptide 1 analogues, have shown to ameliorate postprandial hyperlipidemia. Although sodium glucose cotransporter-2 inhibitors have not been proven to reduce postprandial hyperlipidemia, they reduced fasting apo B48 and remnant lipoprotein cholesterol. In conclusion, it is important to appropriately understand the existence of postprandial hyperlipidemia and to connect it to optimal treatments.

The effects of the consumption of an extract of the brown seaweed Ascophyllum nodosum (BSW) on postprandial glucose and insulin response to white bread were investigated in an acute, randomized, double-blind, three-arm, crossover, controlled trial in healthy, normoglyacemic subjects. Sixteen subjects were administrated either control white bread (50 g total digestible carbohydrates), or white bread with either 500 mg or 1000 mg of BSW extract. Biochemical parameters were measured in venous blood over 3h. Significant inter-individual variation in the glycaemic response to white bread was observed. Analysis of the response of all subjects to either 500 mg or 1000 mg of BSW extract versus control revealed no significant effects of treatments. The variation in response to the control was used to classify individuals into glyacemic responders and non-responders. In the sub-cohort of 10 subjects with peak glucose levels after white bread above 1mmol/L we observed a significant decrease in maximum levels of plasma glucose after the intervention meal with 1000 mg of extract, compared with control. No adverse effects were reported. Further work defining all factors that determine “responders” to the effects of brown seaweed extracts and identify the cohort that would benefit the most from their consumption, is warranted.

After a Century it is time to turn the page on understanding of lactate metabolism and appreciate that lactate shuttling as an important component of intermediary metabolism in vivo. Cell-Cell and intracellular Lactate Shuttles fulfill purposes of energy substrate production and distribution as well as cell signaling under fully aerobic conditions. Recognition of lactate shuttling came first in studies of physical exercise where roles of driver and recipient cells and tissues were obvious. Moreover, the presence of lactate shuttling as part of postprandial glucose disposal has been recognized. Mitochondrial respiration creates the physiological sink for lactate disposal in vivo. Repeated lactate exposure from regular exercise results in adaptive processes such as mitochondrial biogenesis and other healthful circulatory and neurological characteristic such as improved physical work capacity, metabolic flexibility and cognition. The importance of lactate and lactate shuttling in healthful living is further emphasized when lactate signaling and shuttling are dysregulated as occur in illness and injury. Like a Phoenix, lactate rises again in importance in 21^st Century Biology.

Background: Sugar laden foods and carbohydrate rich diets with high glycaemic index intake are associated with weight gain, increased incidence of diabetes and is linked with increased cardiovascular risk. A blend of mulberry leaf extract and apple peel extract (Glubloc™) may reduce postprandial blood glucose surge and insulin response following dietary carbohydrate intake by limiting its digestion and uptake from the gut. Methods: In this randomised, placebo-controlled, crossover study, thirty healthy male and female subjects were supplemented with either placebo or Glubloc™, 10 min before a carbohydrate and sugar rich meal intake. Changes in postprandial blood glucose (upto120 minutes) and insulin levels (at 60 minutes) were measured as the primary endpoints. Changes in blood glucose incremental area under the concentration curve (iAUC), maximum concentration (Cmax) and peak time (Tmax) were compared. Results: Thirty adults (mean age 31±7.2 years, BMI 24±3.8 kg/m2) completed the study and the Glubloc™ blend relative to placebo significantly reduced glucose iAUC at 0.5 h (− 38%, p < 0.0003), 1.0 h (− 30%, p = 0.0007), 1.5 h (− 29%, p = 0.0008), and 2.0 h (− 26%, p = 0.002). A statistically significant reduction in 1 h insulin levels (− 35%, p = 0.029) was observed. Conclusion: A single dose supplementation of Glubloc™ significantly reduced the postprandial blood glucose spike and serum insulin levels. The observation of a significant glucose reduction paralleled with a significant lower insulin response supports a reduced gastrointestinal glucose absorption. None of the subjects experienced any major gastrointestinal side effects. This study builds a body of evidence that the combination of white mulberry leaf and green apple peel extracts (Glubloc™) can be a useful supplement to manage postprandial glucose levels, further studies are necessary to evaluate its potential in type 2 diabetes and the regulation of dysglycaemia.