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.

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-1β 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.

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.