Glycemic responses, appetite ratings and gastrointestinal hormone responses of most common breads consumed in Spain. A randomized control trial in healthy humans

Abstract

The present study was carried out to determine the glycemic index (GI), glycemic load (GL), insulinemic index (InI), appetite ratings and postprandial plasma concentrations of gastrointestinal hormones related to the control of food intake after the ingestion of the five most common breads consumed in Spain with different compositions and manufacturing processes. Twenty-two healthy adults participated in a randomized crossover study. The breads tested were Ordinary, Precooked-Frozen, Candeal-flour, Alfacar whites and Wholemeal. All breads portions were calculated to supply 50 g of available carbohydrates. In addition, 50 g of glucose was used as a reference. A linear mixed-effects model was used to compare data calculated for all breads with glucose load. The GI value varied from 61 for the Wholemeal, to Alfacar 68, Ordinary 76, and 78 and 86 for the Precooked-Frozen and Candeal-flour breads, respectively. Wholemeal and Alfacar had lower GI than glucose. All tested breads had a lower GL (ranged 9 to 18) compared with glucose. Wholemeal GL was similar to Alfacar, but lower than the other white breads. InI were significantly lower for all breads (ranged 68 to 73) compared with glucose, and similar among them. The intake of the Wholemeal bread led to a higher release of gastric inhibitory polypeptide compared with the Ordinary and Precooked breads and to a higher release of pancreatic polypeptide compared with the Precooked-Frozen bread. All breads affected appetite ratings similarly. In conclusion, based on GL, the Wholemeal bread would be expected to exert a favorable glycemic response.

Keywords: appetite ratings; bread; dietary fiber; gastrointestinal hormones; glycemic index; glycemic load; insulinogenic index.

Figure 1

Plasma glucose (a) and insulin (b) concentrations. Values are expressed as the mean ± SEM (n = 20); SEM, standard error of the mean.

Figure 1

Plasma glucose (a) and insulin (b) concentrations. Values are expressed as the mean ± SEM (n = 20); SEM, standard error of the mean.

Figure 2

Plasma gastrointestinal hormones concentrations. (a) grhelin; (b) GLP-1; (c) GIP; (d) PP; values are expressed as the mean ± SEM (n = 20). GIP, gastric inhibitory polypeptide; GLP-1, glucagon-like peptide-1; LMM, linear mixed-effects model; PP, pancreatic polypeptide; SEM, standard error of the mean.

Figure 2

Plasma gastrointestinal hormones concentrations. (a) grhelin; (b) GLP-1; (c) GIP; (d) PP; values are expressed as the mean ± SEM (n = 20). GIP, gastric inhibitory polypeptide; GLP-1, glucagon-like peptide-1; LMM, linear mixed-effects model; PP, pancreatic polypeptide; SEM, standard error of the mean.