Impact of white bread made fromsbeIIwheat flour on postprandial glycaemic response.

Refined starchy foods are usually rapidly digested, leading to poor glycaemic control, but not all starchy foods are the same. Complex carbohydrates like resistant starch (RS) have been shown to reduce the metabolic risk factors for chronic diseases such as hyperglycaemia and overweight. The aim of the project was to develop a semolina-based food made from a starch branching enzyme II (sbeIIa/b-AB) durum wheat mutant with a high RS content and to measure its glycaemic index using a double-blind randomised pilot study. We report here the amylose, RS and non-starch polysaccharide concentration of raw sbeIIa/b-AB and wild-type control (WT) semolina. We measured RS after cooking to identify a model food for in vivo testing. Retrograded sbeIIa/b-AB semolina showed a higher RS concentration than the WT control (RS = 4.87 ± 0.6 g per 100 g, 0.77 ± 0.34 g per 100 g starch DWB, respectively), so pudding was selected as the test food. Ten healthy participants consumed ∼50 g of total starch from WT and sbeIIa/b-AB pudding and a standard glucose drink. Capillary blood glucose concentrations were measured in the fasting and postprandial state (2 h): incremental area-under-the-curve (iAUC) and GI were calculated. We found no evidence of difference in GI between sbeIIa/b-AB pudding and the WT control, but the starch digestibility was significantly lower in sbeIIa/b-AB pudding compared to the WT control in vitro (C₉₀ = 33.29% and 47.38%, respectively). Based on these results, novel sbeIIa/b-AB wheat foods will be used in future in vivo studies to test the effect of different RS concentrations and different food matrices on glycaemia.

Tomatoes are the major dietary source of lycopene, a carotenoid that crosses the blood–brain barrier and exerts antioxidant and anti-inflammatory effects. However, the impact of tomato consumption on cognitive function in healthy adults remains unclear. This study assessed the effects of concentrated tomato paste on cognitive performance and explored potential mechanisms, including brain-derived neurotrophic factor (BDNF) and functional brain connectivity. A randomized, two-period crossover trial (ClinicalTrials.gov: NCT05891977) was conducted in 47 healthy adults aged 40–55 years assigned to two 3-month interventions separated by a 1-month washout: (a) daily consumption of concentrated tomato paste (0.5 g/kg body weight) and (b) a lycopene-restricted control diet. Cognitive performance was evaluated using validated neuropsychological tests (d2-R, Face-Name Associative Memory Exam, Modified Wisconsin Card Sorting Test), alongside plasma lycopene and BDNF, and resting-state functional magnetic resonance imaging (fMRI). Forty-two participants completed the study. Tomato intake improved selective attention (concentration performance: +7.2 points; processing speed: +8.3 points) and associative memory (face-name matching: +0.8 points). Plasma BDNF showed a borderline increase with tomato intake (mean difference 15.2 ng/mL). Resting-state fMRI revealed changes in brain networks, including reduced connectivity in frontoparietal and auditory networks, contrasting with reductions in the dorsal attention network during the control period. These findings provide evidence that tomato consumption may support cognitive function and modulate brain connectivity in healthy middle-aged adults.