Dietary fibre (DF) has been associated with a reduction in postprandial hyperglycaemia1, a risk factor for diabetes and cardiovascular diseases. Current UK recommendation for fibre intake (30 g/day) is not easily achievable. New food products enriched with DF could help the general population to meet the recommendation and provide health benefits. The seed coat (hull, BBH) of broad bean (Vicia faba) is removed during processing and is a food-grade underutilised secondary product rich in DF2. This study aimed to evaluate the acute effects of consuming BBH-enriched bread on postprandial glucose response (PGR).
Nine heathy adults (5 females, 4 males, aged 29-75 years, BMI 22.5-28.0 kg/m2) from Aberdeen area were recruited into a randomised controlled crossover trial. Participants consumed either one portion of control (122 g, 5 g DF) or BBH-enriched bread (156 g, 21% w/w BBH, 23 g DF), providing equal amount of carbohydrate (55 g), and PGR was monitored at 5-minute intervals over 4 hours following bread consumption using Continuous Glucose Monitoring (iPro, Medtronic Ltd). Blood samples were collected at baseline, 15-minute, 30-minute, 45-minute, 60-minute, 90-minute, 120-minute, 180-minute and 240-minute for measuring plasma insulin concentrations using ELISA (Mercodia AB) and plasma lipid profiles (using a Thermo Konelab clinical analyser and kits for HDL, LDL, total cholesterol (TC) and triglycerides (Microgenics GmbH)). PGR and insulin results were calculated as the incremental area under the curve (iAUC) using the trapezoidal method. Data were expressed as mean ±SD. Paired-sample t-test was used for data analysis and two-way repeated ANOVA was used to analyse the effect of interaction between meals and time on plasma lipid profiles (ver. 27.0; SPSS Inc). Statistical significance was defined as p<0.05.
The iAUC of glucose responses for BBH-enriched and control breads were similar (iAUC0-240min= 223.6 ± 156.5, 241.1 ± 142.9 mmol x time/L respectively, p=0.700). The insulin response following control bread (iAUC0-240min = 3117.2 ± 1126.8 mmol x time/L) was significantly higher than the BBH-enriched bread (iAUC0-240min= 3010.4 ± 1449.5 mmol x time/L, p=0.039). Plasma lipid profiles were similar between treatments (p>0.05). There were significant effects of time (baseline to 4-hour) on TC (reduced by 0.07 and 0.25 mmol/L in control and BBH treated respectively, p=0.008), HDL (reduced by 0.01 and 0.10 mmol/L in control and BBH treated respectively, p=0.005) and LDL (reduced by 0.07 and 0.14 mmol/L in control and BBH treated respectively, p=0.011). There were no significant meal x time interaction effects on changes of plasma lipid profiles (p>0.05).
Addition of 21% BBH in bread did not affect PGR and postprandial plasma lipids but significantly reduced insulin response. These effects may be driven by DF and possibly phenolic compounds present in BBH. Further longer studies appropriately powered are required to confirm these results.
1. de Carvalho CM, de Paula TP, Viana LV et al. (2017) Am. J. Clin. Nutr. 106(5), 1238-1245.
2. Ni QQ, Ranawana V, Hayes HE et al. (2020) Foods9, 1192.

Dietary fibre (DF) has been associated with a reduction in postprandial hyperglycaemia1, a risk factor for diabetes and cardiovascular diseases. Current UK recommendation for fibre intake (30 g/day) is not easily achievable. New food products enriched with DF could help the general population to meet the recommendation and provide health benefits. The seed coat (hull, BBH) of broad bean (_Vicia faba_) is removed during processing and is a food-grade underutilised secondary product rich in DF2. This study aimed to evaluate the acute effects of consuming BBH-enriched bread on postprandial glucose response (PGR).
Nine heathy adults (5 females, 4 males, aged 29-75 years, BMI 22.5-28.0 kg/m2) from Aberdeen area were recruited into a randomised controlled crossover trial. Participants consumed either one portion of control (122 g, 5 g DF) or BBH-enriched bread (156 g, 21% w/w BBH, 23 g DF), providing equal amount of carbohydrate (55 g), and PGR was monitored at 5-minute intervals over 4 hours following bread consumption using Continuous Glucose Monitoring (iPro, Medtronic Ltd). Blood samples were collected at baseline, 15-minute, 30-minute, 45-minute, 60-minute, 90-minute, 120-minute, 180-minute and 240-minute for measuring plasma insulin concentrations using ELISA (Mercodia AB) and plasma lipid profiles (using a Thermo Konelab clinical analyser and kits for HDL, LDL, total cholesterol (TC) and triglycerides (Microgenics GmbH)). PGR and insulin results were calculated as the incremental area under the curve (iAUC) using the trapezoidal method. Data were expressed as mean ±SD. Paired-sample t-test was used for data analysis and two-way repeated ANOVA was used to analyse the effect of interaction between meals and time on plasma lipid profiles (ver. 27.0; SPSS Inc). Statistical significance was defined as p<0.05.
The iAUC of glucose responses for BBH-enriched and control breads were similar (iAUC0-240min= 223.6 ± 156.5, 241.1 ± 142.9 mmol x time/L respectively, p=0.700). The insulin response following control bread (iAUC0-240min = 3117.2 ± 1126.8 mmol x time/L) was significantly higher than the BBH-enriched bread (iAUC0-240min= 3010.4 ± 1449.5 mmol x time/L, p=0.039). Plasma lipid profiles were similar between treatments (p>0.05). There were significant effects of time (baseline to 4-hour) on TC (reduced by 0.07 and 0.25 mmol/L in control and BBH treated respectively, p=0.008), HDL (reduced by 0.01 and 0.10 mmol/L in control and BBH treated respectively, p=0.005) and LDL (reduced by 0.07 and 0.14 mmol/L in control and BBH treated respectively, p=0.011). There were no significant meal x time interaction effects on changes of plasma lipid profiles (p>0.05).
Addition of 21% BBH in bread did not affect PGR and postprandial plasma lipids but significantly reduced insulin response. These effects may be driven by DF and possibly phenolic compounds present in BBH. Further longer studies appropriately powered are required to confirm these results.
1. de Carvalho CM, de Paula TP, Viana LV et al. (2017) _Am. J. Clin. Nutr_. 106(5), 1238-1245.
2. Ni QQ, Ranawana V, Hayes HE et al. (2020) _Foods_9, 1192.

The effect of broad bean hull on postprandial glucose response: a pilot study

The Nutrition Society Summer Conference 2022 is hosted in collaboration between Sheffield Hallam University, University of Sheffield and Sheffield City Council. It will be the first in-person Summer Conference since the pandemic, held at the Sheffield Hallam University city centre campus.

Sustainability is high on the agenda for individuals and for society as a whole, recent meetings such as COP 26 have highlighted the urgency of addressing climate change, of which food systems are a key factor.

The overarching theme of this conference highlights sustainability- sustainability is a large, diverse and contemporary issue consisting of environmental, societal and health perspectives which will be addressed from varying angles. 

This meeting will consider how to build ethical food systems, tackle inequalities and sustain health and wellbeing for future generations.

The Organising Committee have considered local food provision and will offer you a chance to explore Sheffield and its local produce.