Positive contribution of hydroxytyrosol-enriched wheat bread to HbA1c levels, lipid profile, markers of inflammation and body weight in subjects with overweight/obesity and type 2 diabetes mellitus.

PURPOSE: The aim of the present study was to assess the impact of the daily consumption of bread enriched with hydroxytyrosol on HbA1c and blood lipid levels, inflammatory markers and weight loss. METHODS: Sixty adults with overweight/obesity and type 2 diabetes mellitus (29 male, 31 female) participated in a 12-week dietary intervention based on the Mediterranean diet and consumed daily 60 g of conventional whole wheat bread (WWB) or whole wheat bread enriched with hydroxytyrosol (HTB). Anthropometric characteristics were measured and venous blood samples were collected at baseline and at the end of the intervention. RESULTS: Both groups experienced significant weight loss, body fat and waist circumference decrease (p < 0.001). Nonetheless, a greater body fat mass decrease was observed in the HTB group compared to the WWB group (14.4 ± 1.6 vs 10.2 ± 1.1%, p = 0.038). Significant reductions were also reported in fasting glucose, HbA1c and blood pressure in both groups (p < 0.05). Regarding glucose and HbA1c, greater decreases were observed in the intervention group (101.4 ± 19.9 vs. 123.2 ± 43.4 mg/dL, p = 0.015 and 6.0 ± 0.6 vs. 6.4 ± 0.9%, p = 0.093, respectively). At HTB group, significant reductions in blood lipid, insulin, TNF-αand adiponectin levels (p < 0.05) and a marginally significant reduction in leptin levels (p = 0.081) were also reported. CONCLUSION: Enrichment of bread with HT resulted in significant body fat mass reduction and positive effects on fasting glucose, insulin and HbA1c levels. It also contributed to reductions in inflammatory markers and blood lipid levels. Incorporation of HT in staple foods, like bread, may improve their nutritional profile and, in terms of a balanced diet, may contribute to the management of chronic diseases. TRIAL REGISTRATION: The study was prospectively registered in clinicaltrials.gov (24th May 2021). CLINICALTRIALS: gov Identifier: NCT04899791.

Physical properties, sensory acceptance, postprandial glycemic response, and satiety of cereal based foods enriched with legume flours: a review.

Legumes are rich in proteins and widely consumed around the world. Their consumption has been associated with improved glycemic and lipidemic profile and positive alterations of gut microbiota. These beneficial effects have created a growing scientific interest in the role of legume-enriched foods on the promotion of human health. The aim of this review was to critically record the studies examining the nutritional value and textural properties of these products, as well as their efficacy on lowering postprandial glucose response and satiety. Reviewed data have shown that cereal products with high nutritional value are formulated when fortified with legume flours. The postprandial glucose response appears to be ameliorated and the enriched foods have a medium or a low glycemic index, however not enough data are presented referring to the appetite hormones responses. Textural properties are affected by the addition of legumes and occasionally, when substitution level is high, the final product has not acceptable odor and appearance. To overcome this barrier, particular food processes such as fermentation, extrusion and addition of hydrocolloids, are used and have shown great results on the textural and sensory properties of the final products. The development of healthy legume-enriched cereal-based products is of great importance for the increase of legume consumption and the promotion of public health.

Positive postprandial glycaemic and appetite-related effects of wheat breads enriched with either α-cyclodextrin or hydroxytyrosol/α-cyclodextrin inclusion complex.

PURPOSE: Enrichment of wheat bread with either α-cyclodextrin (α-CD) or an inclusion complex of hydroxytyrosol (HT) and α-CD was performed to examine potential postprandial benefits. METHODS: Ten healthy normoglycaemic adults were provided with either a glucose solution (reference food, GS), white wheat bread (WB), wheat bread enriched with α-CD (α-CDB) or wheat bread enriched with HT/α-CD complex ((HT + α-CD)B), with 1-week intervals in amounts that yielded 50 g of available carbohydrates. Venous blood samples were collected before consumption and at 15, 30, 45, 60, 90, 120 and 180 min, postprandially. Glycaemic, insulinaemic and appetite hormone responses as well as glycaemic index (GI) and subjective appetite ratings were evaluated. RESULTS: Both enriched breads were characterized as low GI foods (α-CDB:49.7, (HT + α-CD)B:40.0) and presented similar reduction in glucose, insulin and GLP-1 responses. Significant differences were found in glucose values 45 min after (HT + α-CD)B consumption compared to α-CDB (P < 0.05) as well as in serum ghrelin, 120 min postprandially, between (HT + α-CD)B and WB in (- 90.55 ± 29.17 and 16.53 ± 21.78 pg/dL, respectively, P < 0.05). Neither of the enriched breads prevailed regarding the induced self-reported satiety. However, their consumption led to a lower desire for the next meal compared to WB. CONCLUSION: Enrichment of bread with α-CD resulted in positive effects on postprandial glycaemia and induced satiety. Incorporation of encapsulated HT offered similar overall acceptability, due to the bitter taste-masking effect provided by α-CD, and a slightly additional positive effect in postprandial glycaemia and satiety. The development of foods with favorable metabolic effects is of great importance for the prevention of chronic diseases. The study was prospectively registered in clinicaltrials.gov (NCT04725955, date: 27th January 2021).

Enrichment of bread with beta-glucans or resistant starch induces similar glucose, insulin and appetite hormone responses in healthy adults.

PURPOSE: ß-Glucans (ßG) and resistant starch (RS) are known for their effects on the improvement of glucose tolerance and enhancement of insulin sensitivity. Enrichment of bread with ßG or RS was performed to examine potential postprandial benefits regarding gastrointestinal hormone responses. METHODS: Ten healthy normoglycaemic adults participated in the study and were provided with either a glucose solution (reference food, GS) or bread enriched with ß-glucans (ßGB) (3.6 g/30 g available CHO) or bread enriched with resistant starch (RSB) (15% of total starch), with 1-week intervals in amounts that yielded 50 g of available carbohydrates. Venous blood samples were collected before consumption and at 15, 30, 45, 60, 90, 120 and 180 min postprandially. Glucose, insulin, ghrelin, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) responses as well as glycaemic index (GI) and subjective appetite ratings were evaluated. RESULTS: Ingestion of ßGB and RSB elicited lower incremental area under the curve (iAUC) for glycaemic response compared to GS (P < 0.05). Both breads demonstrated a low GI (ßGB: 48, RSB: 40). There were no significant differences in insulin response, ghrelin, GLP-1 or PYY between the two breads. A significantly lower desire to eat and higher fullness were detected 15 min after ßGB and RSB consumption and until 180 min (P < 0.05 compared to GS). CONCLUSION: Enrichment of bread with either ßG or RS produced a low GI product but the two breads were not significantly different in relation to insulin, ghrelin, GLP-1 and PYY responses. The development of bread products which cause improved metabolic effects is of great importance for the promotion of public health.

A systematic review of vitamin D status in southern European countries.

PURPOSE: Despite an acknowledged dearth of data on serum 25-hydroxyvitamin D (25(OH)D) concentrations from Southern European countries, inter-country comparison is hampered by inconsistent data reporting. The purpose of the current study was to conduct a systematic literature review of available data on serum 25(OH)D concentrations and estimate vitamin D status in Southern European and Eastern Mediterranean countries, both at a population level and within key population subgroups, stratified by age, sex, season and country. METHODS: A systematic review of the literature was conducted to identify and retrieve scientific articles reporting data on serum 25(OH)D concentration and/or vitamin D status following standard procedures. RESULTS: Data were extracted from 107 studies, stratified by sex and age group, representing 630,093 individuals. More than one-third of the studies reported mean 25(OH)D concentrations below 50 nmol/L and ~ 10% reported mean serum 25(OH)D concentrations below 25 nmol/L. Overall, females, neonates/ infants and adolescents had the higher prevalence of poor vitamin D status. As expected, there was considerable variability between studies. Specifically, mean 25(OH)D ranged from 6.0 (in Italian centenarians) to 158 nmol/L (in elderly Turkish men); the prevalence of serum 25(OH)D < 50 nmol/L ranged from 6.8 to 97.9% (in Italian neonates). CONCLUSIONS: Contrary to expectations, there was a high prevalence of low vitamin D status in the Southern Europe and the Eastern Mediterranean regions, despite abundant sunshine. These data further emphasize the need for strategies, such as fortification of foods with vitamin D and/or vitamin D supplementation, which will be tailored to the needs of specific population groups with higher risk of insufficiency or deficiency, to efficiently tackle the pandemic of hypovitaminosis D in Europe.

Wheat Biscuits Enriched with Plant-Based Protein Contribute to Weight Loss and Beneficial Metabolic Effects in Subjects with Overweight/Obesity.

The present study aimed to assess the impact of daily consumption of a snack fortified with plant proteins with high content in amino acids with appetite regulating properties (BCAAs and L-arginine), as part of a dietary intervention, on weight loss. Seventy adults without diabetes (26 male, 44 female) and with overweight/obesity participated in a 12-week restricted dietary intervention and were randomized to either a control or an intervention group, consuming daily 70 g of conventional wheat biscuits (CB) or an isocaloric amount of wheat biscuits enriched with plant proteins (PB) originating from legumes and seeds, respectively. Anthropometric characteristics were measured and venous blood samples were collected at baseline and at the end of the intervention. Decreases in body weight, body fat mass and waist circumference were observed in both groups. Participants in the intervention group experienced greater weight loss (7.6 ± 2.7 vs. 6.2 ± 2.7%, p = 0.025) and marginally significant larger decrease in body fat mass (4.9 ± 2.2 vs. 3.9 ± 2.4 kg, p = 0.059). A moderate reduction in IL-1ß levels (p = 0.081), a significantly higher decrease in TNF-α levels (p < 0.001) and a marginally significant greater leptin decrease (p = 0.066) in subjects of the PB group were noticed. Greater reductions in caloric and carbohydrate intake and a trend towards a higher decrease in fat intake were also observed in participants of this group. Incorporation of plant-based proteins with high content in amino acids with appetite-regulating properties in wheat biscuits may contribute to greater weight loss and improvement of metabolic parameters in subjects who are overweight or obese. Protein enrichment of snacks offers a beneficial qualitative manipulation that could be successfully incorporated in a diet plan.

Host-guest inclusion complexes of hydroxytyrosol with cyclodextrins: Development of a potential functional ingredient for food application.

Hydroxytyrosol (HT), a potent phenolic phytochemical, exerts positive health effects due to its antioxidant properties. However, it is highly reactive to oxygen, light, and heat and presents high instability. Alpha- and beta-cyclodextrin (α-CD, ß-CD) have structures that allow them to encapsulate a variety of hydrophobic molecules. The aim of this study was to examine the outcomes of the inclusion of HT into α-CD and ß-CD. Aqueous solutions of HT and either α-CD or ß-CD were prepared and freeze-drying was applied for the encapsulation, in 1:1 and 2:1 molar ratios. The produced solid complexes were studied and characterized using NMR spectroscopy, differential scanning calorimetry (DSC) and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). Encapsulation efficiency (EE%), stability, and in vitro release of the encapsulated complexes under simulated digestion conditions were also evaluated. In both DSC thermograms and FTIR spectra of the inclusion complexes, absence of the characteristic peaks of HT and shifts of the CDs peaks were observed, showing an interaction between the molecules. NMR suggested a stronger complex formed between ß-CD and HT. The EE% of ß-CD/HT (1:1 and 2:1) complexes and α-CD/HT (1:1) complex was found to be higher (83%, 76%, 78%, respectively), compared to α-CD/HT (2:1) (51%). Data obtained support the encapsulation of HT in both CDs, revealing a potential interaction between them and an improvement in HT's thermal stability. Regarding the in vitro release study, both CD complexes had similar behavior and a controlled release of HT in the intestinal site was observed. PRACTICAL APPLICATION: The encapsulation of hydroxytyrosol in cyclodextrins resulted in white amorphous food-grade powders with no aroma and taste. Incorporation of these powders in foods could lead to an increase in their antioxidant content and offer an additional nutritional value.

Postprandial Glucose and Gastrointestinal Hormone Responses of Healthy Subjects to Wheat Biscuits Enriched with L-Arginine or Branched-Chain Amino Acids of Plant Origin.

The study investigates the effects of wheat biscuits supplemented with plant flours originating from legumes/seeds enriched either in L-arginine (L-arg) or branched-chain amino acids (BCAAs) on postprandial glucose response of healthy subjects. Gastrointestinal hormone and amino acid responses as well as subjective appetite sensations are also evaluated. Subjects consumed wheat-based biscuits, enriched either in L-arg (ArgB) or BCAAs (BCAAsB) or a conventional wheat biscuit (CB) or a glucose solution (GS) in an acute randomized crossover design. Responses of glucose, insulin, ghrelin, glucagon-like peptide-1 (GLP-1), peptide YY (PYY) and glicentin, as well as those of L-arginine, L-leucine, L-isoleucine and L-valine, were evaluated over 180 min. Consumption of ArgB and BCAAsB elicited lower glucose iAUC compared to GS (p < 0.05). A lower iAUC for insulin was observed after consumption of BCAAsB (p < 0.05 compared to CB and ArgB), while ArgB elicited higher iAUC for GLP-1 accompanied by higher glicentin response (p < 0.05 compared to CB). BCAAsB and ArgB increased postprandial amino acid concentrations and caused stronger satiety effects compared to CB. Increasing protein content of wheat biscuits with supplementation of plant flours originating from legumes/seeds decreases postprandial glycemia and provides with healthier snack alternatives which can easily be incorporated into diet.

Effects of 12-week, non-energy-restricted dietary intervention with conventional yogurt οn appetite hormone responses of type 2 diabetic patients.

Hunger-reducing effects and beneficial changes in gastrointestinal hormones have been reported, in overweight/obese individuals consuming dairy while yogurt takes pride of place due to its unique structure and composition. Although the contribution of yogurt to metabolic regulation has received growing attention, the research studies which examine its role on appetite are limited, especially regarding type 2 diabetes mellitus (T2DM) patients. The aim of the present study was to investigate the effects of non-fat, conventional yogurt consumption on appetite hormone responses of T2DM patients following a non-energy-restricted diet. Overweight subjects participated in a 12-week dietary intervention including 2 meals/day (2 × 200 g) of yogurt. At the beginning and the end of the intervention, a mixed meal tolerance test assessing the postprandial response of glucose, insulin, ghrelin, glucagon-like peptide-1 (GLP-1), and peptide-YY (PYY) was performed. Subjective appetite ratings were also evaluated. Area under the curve for glucose, insulin, ghrelin, GLP-1, and PYY responses did not differ after the 12-week intervention with yogurt (p > .05) as well as for subjective appetite ratings (p > .05). No significant differences were indicated at specific time points in any of the examined parameters. Regular consumption of non-fat, conventional yogurt for 12-week duration does not affect appetite hormone responses in overweight patients with T2DM following a non-energy-restricted diet.

Daily consumption of fruit-flavored yoghurt enriched with vitamins B contributes to lower energy intake and body weight reduction, in type 2 diabetic patients: a randomized clinical trial.

Yoghurt naturally contains vitamins of B-complex which play a central role in energy metabolism. This study investigates the effects of consumption of yoghurt enriched with vitamins B, in comparison with conventional yoghurt, on body weight management and glycemic control of patients with Type 2 Diabetes Mellitus (T2DM). Thirty-three overweight/obese patients (BMI 27-36 kg m-2) were randomized into two groups receiving two servings of non-fat yoghurt per day, either strawberry-flavored enriched with vitamins B1, B5 and B6 (VY) or conventional (CY) for 12 weeks. At the beginning and the end of the dietary intervention, anthropometric characteristics, biochemical parameters, glycosylated haemoglobin (HbA1c), interleukin-6 (IL-6) and interleukin-1b (IL-1b), vitamins B and homocysteine concentrations were determined. Dietary assessments were also performed. At the end of the intervention, body weight and BMI were reduced in the VY group (86.5 ± 3.1 vs. 87.7 ± 3.0 kg, and 29.2 ± 1.0 vs. 29.6 ± 0.9 kg m-2, respectively, P < 0.05) and dietary intake was lower compared to the CY group (7277.6 ± 332.6 vs. 9918.2 ± 612.1 kJ day-1, P < 0.05). HbA1c was marginally reduced in the VY group (6.2 ± 0.2 vs. 6.4 ± 0.3%, P = 0.08), concentrations of B1, B2 and B6 were increased (63.8 ± 5.6 vs. 52.8 ± 1.7 µg L-1, P = 0.09, 9.2 ± 1.5 vs. 6.9 ± 1.4 µg L-1, P < 0.05 and 23.0 ± 2.8 vs. 14.9 ± 1.2 µg L-1, P < 0.05, respectively) and a trend towards reduced homocysteine concentrations was observed (16.9 ± 1.7 vs. 18.3 ± 2.0 µmol L-1, P = 0.06). IL-6 was decreased in both groups but significantly in the CY group (1.33 ± 0.13 vs. 1.67 ± 0.63 pg mL-1, P < 0.05). Daily consumption of fruit-flavored yoghurt enriched with vitamins B facilitates body weight management and improves vitamins B status and homocysteine levels in overweight/obese T2DM patients.