Postprandial glucose metabolism and SCFA after consuming wholegrain rye bread and wheat bread enriched with bioprocessed rye bran in individuals with mild gastrointestinal symptoms

• Published in: Nutrition journal Vol. 13; no. 1; p. 104
• Main Authors: Lappi, Jenni, Mykkänen, Hannu, Bach Knudsen, Knud Erik, Kirjavainen, Pirkka, Katina, Kati, Pihlajamäki, Jussi, Poutanen, Kaisa, Kolehmainen, Marjukka
• Format: Journal Article
• Language: English
• Published: England Springer-Verlag 04.11.2014; BioMed Central Ltd; BioMed Central
• Subjects: Adult; Aged; Area Under Curve; Blood Glucose - metabolism; Body Mass Index; Body Weight; Bread; breads; butyrates; Cholesterol - blood; Control equipment industry; Cross-Over Studies; Diet; Dietary Fiber; Energy Intake; Fasting; Female; gastrointestinal system; Glucose; Glucose metabolism; Grain; Health aspects; Humans; Insulin; Insulin - blood; insulin secretion; Male; Meals; metabolism; Middle Aged; Patient Compliance; Physiological aspects; Postprandial Period - physiology; propionic acid; rye; rye bran; Secale; short chain fatty acids; sourdough; Studies; test meals; Triglycerides - blood; Triticum; Type 2 diabetes; Weight control; wheat; women; United States
• ISSN: 1475-2891; 1475-2891
• DOI: 10.1186/1475-2891-13-104

BACKGROUND: Rye bread benefits glucose metabolism. It is unknown whether the same effect is achieved by rye bran-enriched wheat bread. We tested whether white wheat bread enriched with bioprocessed rye bran (BRB + WW) and sourdough wholegrain rye bread (WGR) have similar effects on glucose metabolism and plasma level of short chain fatty acids (SCFAs). METHODS: Twenty-one (12 women) of 23 recruited subjects completed an intervention with a four-week run-in and two four-week test periods in cross-over design. White wheat bread (WW; 3% fibre) was consumed during the run-in, and WGR and BRB + WW (10% fibre) during the test periods. A meal test providing 51/33/11 E % from carbohydrates/fat/protein was conducted at the end of each period. Fasting and postprandial plasma samples were analysed for glucose, insulin, and SCFA. RESULTS: Glucose and insulin responses and plasma concentrations of SCFAs to the meal test were similar between the WGR and BRB + WW periods. When compared to the WW period, postprandial insulin concentration at 120 min was lower (p = 0.023) and the first-phase insulin secretion improved (p = 0.033) only after the WGR period, whereas postprandial concentrations of butyrate (p < 0.05) and propionate (p = 0.009) at 30 min increased during both rye bread periods. CONCLUSIONS: Beneficial effects of WGR over white wheat bread on glucose and SCFA production were confirmed. The enrichment of the white wheat bread with bioprocessed rye bran (BRB + WW) yielded similar but not as pronounced effects than WGR when compared to WW alone. Postprandially measured glucose metabolism and concentrations of SCFAs provided additional information along with fasting measurements.