Meal skipping has become an increasing trend of the modern lifestyle that may lead to obesity and type 2 diabetes. We investigated whether the timing of meal skipping impacts these risks by affecting circadian regulation of energy balance, glucose metabolism, and postprandial inflammatory responses. In a randomized controlled crossover trial, 17 participants [body mass index (in kg/m): 23.7 ± 4.6] underwent 3 isocaloric 24-h interventions (55%, 30%, and 15% carbohydrate, fat, and protein, respectively): a breakfast skipping day (BSD) and a dinner skipping day (DSD) separated by a conventional 3-meal-structure day (control). Energy and macronutrient balance was measured in a respiration chamber. Postprandial glucose, insulin, and inflammatory responses in leukocytes as well as 24-h glycemia and insulin secretion were analyzed. When compared with the 3-meal control, 24-h energy expenditure was higher on both skipping days (BSD: +41 kcal/d; DSD: +91 kcal/d; both < 0.01), whereas fat oxidation increased on the BSD only (+16 g/d; < 0.001). Spontaneous physical activity, 24-h glycemia, and 24-h insulin secretion did not differ between intervention days. The postprandial homeostasis model assessment index (+54%) and glucose concentrations after lunch (+46%) were, however, higher on the BSD than on the DSD (both < 0.05). Concomitantly, a longer fasting period with breakfast skipping also increased the inflammatory potential of peripheral blood cells after lunch. Compared with 3 meals/d, meal skipping increased energy expenditure. In contrast, higher postprandial insulin concentrations and increased fat oxidation with breakfast skipping suggest the development of metabolic inflexibility in response to prolonged fasting that may in the long term lead to low-grade inflammation and impaired glucose homeostasis. This trial was registered at clinicaltrials.gov as NCT02635139.

Coffee silver skin is produced in large amounts as a by-product during the coffee roasting process. In this study, coffee silver skin of the species Coffea arabica L. and Coffea canephora Pierre ex A. Froehner as well as silver skin pellets produced in the coffee industry were characterized with respect to both nutritional value and potential heat-induced contaminants. Enzymatic-gravimetric/chromatographic determination of the dietary fiber content showed values ranging from 59 to 67 g/100 g with a comparably high portion of soluble fiber, whereas low molecular weight soluble fiber was not detected. Compositional and methylation analysis indicated the presence of cellulose and xylans in the insoluble dietary fiber fraction, whereas pectic polysaccharides dominate the soluble dietary fiber fraction. The protein content as determined by the Kjeldahl method was in the range of 18 to 22 g/100 g, and all essential amino acids were present in coffee silver skin; whereas fat contents were low, high ash contents were determined. Elemental analysis by inductively coupled plasma mass spectrometry (ICP-MS) showed the presence of macroelements in large amounts, whereas toxic mineral elements were only detected in trace amounts or being absent. Acrylamide was quantified with levels of 24–161 µg/kg. Although 5-hydroxymethylfurfural was detected, its concentration was below the limit of determination. Furfuryl alcohol was not detected.

Intake of sugar-sweetened beverages (SSB) may contribute to cardiovascular risk. The aim of this study was to investigate whether functional sugars with low compared to high glycemic index (GI) have beneficial effects on arterial stiffness during a period of low-physical activity. In a controlled cross-over dietary intervention (55% CHO, 30% fat, 15% protein), 13 healthy men (age: 23.7 ± 2.2 years, body mass index: 23.6 ± 1.9 kg/m2) completed 2 × 1 week of low physical activity following 1 week of normal physical activity (2363 ± 900 vs. 11,375 ± 3124 steps/day). During inactive phases participants consumed either low-GI (isomaltulose) or high-GI SSB (maltodextrin-sucrose), providing 20% of energy requirements. Postprandial vasodilatation (augmentation index, AIx), insulin sensitivity (IS) and Glucagon-like-peptide 1 (GLP-1) responses were measured during a meal test before and after SSB-intervention. Compared to maltodextrin-sucrose-SSB, postprandial vasodilatation was prolonged (AIx after 120 min: 9.9% ± 4.3% vs. 11.4% ± 3.7%, p < 0.05) and GLP-1 secretion was higher with isomaltulose-SSB (total area under the GLP-1 curve (tAUCGLP)-1: 8.0 ± 4.4 vs. 5.4 ± 3.4 pM × 3 h; p < 0.05). One week of low-physical activity led to impaired IS that was attenuated with low-GI SSB consumption, but did not affect arterial stiffness (p > 0.05). Higher postprandial GLP-1 secretion after intake of low compared to high-GI beverages may contribute to improved postprandial vasodilatation. Although one week of low-physical activity led to marked impairment in IS, it had no effect on arterial stiffness in healthy men.

Thymus carnosus Boiss. is a near-threatened species, and, as for many species, its potential for medicinal purposes may be lost if measures towards plant protection are not taken. A way of preserving these species is to increase knowledge about their medicinal properties and economic potential. Thus, with the objective of studying the potentiality of introducing T. carnosus as a crop, the stability of the phytochemical profile of T. carnosus was studied during a period of three years by comparing the phytochemical profile of extracts obtained from plants harvested in two different edaphoclimatic locations, as well as by comparing the respective bioactivities, namely, antioxidant, antidiabetic, antiaging, and neuroprotective activities. It was reported, for the first time, the effect of annual variation and geographic location in the phytochemical composition of aqueous decoction and hydroethanolic extracts of T. carnosus. In addition, the presence of two salvianolic acid B/E isomers in T. carnosus extracts is here described for the first time. Despite the variations in phytochemical composition, according to harvesting location or year, T. carnosus extracts maintain high antioxidant activity, assessed by their capacity to scavenge ABTS•+, •OH , NO•, O2•− radicals, as well as to prevent β-carotene bleaching. All extracts presented significant potential to inhibit acetylcholinesterase (AChE), tyrosinase, and α-glucosidase, denoting neuroprotective, anti-aging, and anti-diabetic potential. In conclusion, the vegetative stage and location of harvest are key factors to obtain the maximum potential of this species, namely, a phytochemical profile with health benefit bioactivities.

Food by-products can be used as natural and sustainable food ingredients. However, a modification is needed to improve the technofunctional properties according to the specific needs of designated applications. A lab-scale twin-screw extruder was used to process enzymatically treated apple pomace from commercial fruit juice production. To vary the range of the thermomechanical treatment, various screw speeds (200, 600, 1000 min−1), and screw configurations were applied to the raw material. Detailed chemical and functional analyses were performed to develop a comprehensive understanding of the impact of the extrusion processing on apple pomace composition and technofunctional properties as well as structures of individual polymers. Extrusion at moderate thermomechanical conditions increased the water absorption, swelling, and viscosity of the material. An increase in thermomechanical stress resulted in a higher water solubility index, but negatively affected the water absorption index, viscosity, and swelling. Scanning electron microscopy showed an extrusion-processing-related disruption of the cell wall. Dietary fiber analysis revealed an increase of soluble dietary fiber from 12.6 to 17.2 g/100 g dry matter at maximum thermo-mechanical treatment. Dietary fiber polysaccharide analysis demonstrated compositional changes, mainly in the insoluble dietary fiber fraction. In short, pectin polysaccharides seem to be susceptible to thermo-mechanical stress, especially arabinans as neutral side chains of rhamnogalacturonan I.