UPLC-QTOF/MS metabolic profiling unveils urinary changes in humans after a whole grain rye versus refined wheat bread intervention.

Scope: Non-targeted urine metabolite profiling has not been previously exploited in the field of whole grain (WG) products. WG products, particularly rye, are important elements in a healthy Nordic diet. The aim of this study was to identify novel urinary biomarkers of WG rye bread (RB) intake in a randomised crossover study with RB versus refined wheat bread (WB).

Metabolomics reveals the metabolic shifts following an intervention with rye bread in postmenopausal women--a randomized control trial.

Background: Epidemiological studies have consistently shown that whole grain (WG) cereals can protect against the development of chronic diseases, but the underlying mechanism is not fully understood. Among WG products, WG rye is considered even more potent because of its unique discrepancy in postprandial insulin and glucose responses known as the rye factor. In this study, an NMR-based metabolomics approach was applied to study the metabolic effects of WG rye as a tool to determine the beneficial effects of WG rye on human health.

Metabolomic analysis of plasma metabolites that may mediate effects of rye bread on satiety and weight maintenance in postmenopausal women.

The evidence of the beneficial health effects of dietary fiber and whole grain consumption is strong, but the underlying mechanisms are not completely understood. Here, we investigate how the consumption of high-fiber rye bread (RB) or white-wheat bread (WB) modifies the plasma metabolomic profiles in postmenopausal women. The study was a randomized crossover trial consisting of 8-wk intervention periods and an 8-wk washout period.

Long-term repeatability of measures of early insulin secretion derived from an intravenous glucose tolerance test and conversion from impaired glucose tolerance to diabetes.

Aim: We assessed the long-term repeatability of the acute insulin response (AIR) and sensitivity index (S(I)) derived from the frequently sampled intravenous glucose tolerance test (FSIGT).

Methods: An FSIGT was performed in 20 women who participated in a 6.5-month rye- and wheat-bread intervention trial, 70 men and women with impaired fasting glycaemia (IFG) or impaired glucose tolerance (IGT) who participated in the Genobin study, and 81 men and women with IGT who participated in the Finnish Diabetes Prevention Study (DPS).

Plasma ghrelin levels after two high-carbohydrate meals producing different insulin responses in patients with metabolic syndrome.

Ghrelin is an orexigenic peptide produced in the stomach and its plasma levels are decreased acutely in response to ingested nutrients. To further clarify the role of insulin on ghrelin secretion, the present study was designed to investigate whether circulating ghrelin is affected differently by two mixtures of whole-grain breads known to produce low or high insulin responses in obese non-diabetic subjects with metabolic syndrome. After an overnight fast eight obese subjects with the metabolic syndrome (3 men and 5 women; BMI 33.

Dietary carbohydrate modification enhances insulin secretion in persons with the metabolic syndrome.

Background: The metabolic syndrome markedly increases the risk of type 2 diabetes and cardiovascular disease, but the influence of dietary modification on insulin and glucose metabolism independent of weight loss is still poorly understood.

Objective: Our aim was to test whether carbohydrate dietary modifications improve insulin sensitivity and secretion and glucose tolerance in overweight or obese persons with the metabolic syndrome, even in the absence of weight loss.

Design: We assessed the effect of carbohydrate modification on insulin and glucose metabolism in 72 overweight or obese men and women with the metabolic syndrome, as determined according to the National Cholesterol Education Program criteria.

Whole-grain rye bread consumption by women correlates with plasma alkylresorcinols and increases their concentration compared with low-fiber wheat bread.

Whole-grain rye and wheat products are rich in lignans, the precursors of enterolactone (ENL) and alkylresorcinols (ARs), which are phenolic lipids. In this crossover trial, we examined the effect of whole-grain rye bread compared with low-fiber wheat bread on plasma AR levels. Women (n = 39) aged 59 +/- 0.

Structural differences between rye and wheat breads but not total fiber content may explain the lower postprandial insulin response to rye bread.

Background: Rye bread has a beneficial effect on the postprandial insulin response in healthy subjects. The role of rye fiber in insulin and glucose metabolism is not known.

Objective: The aim of the study was to determine the effect of the content of rye fiber in rye breads on postprandial insulin and glucose responses.

New insight into butyrate metabolism.

Butyrate is a C4 acid produced by microbial fermentation of carbohydrates and protein in the large intestine of all animal species. The factor of prime importance for the production rate of butyrate in the lower gut is type and levels of non-digestible carbohydrates entering the large intestine. It was previously believed that 85-90 % of the butyrate produced in the gut was cleared when passing the gut epithelium, but recent studies with catheterised pigs have shown that the concentration of butyrate in the portal vein is strongly influenced by the production rate in the large intestine.

High-fiber rye bread and insulin secretion and sensitivity in healthy postmenopausal women.

Background: Fiber and whole-cereal intakes may protect against hyperinsulinemia and the risk of type 2 diabetes.

Objective: The aim was to study whether the long-term use of high-fiber rye bread and white-wheat bread modifies glucose and insulin metabolism in healthy postmenopausal women.

Design: The study was a randomized crossover trial consisting of 8-wk test and 8-wk washout periods.

Postprandial glucose, insulin, and incretin responses to grain products in healthy subjects.

Background: Various botanical and structural characteristics of starchy food modify the postprandial glucose and insulin responses in humans.

Objective: We investigated what factors in grain products affect human glucose and insulin responses and elucidated the mediating mechanisms.

Design: Ten men and 10 women [mean age: 28 +/- 1 y; mean body mass index (in kg/m(2)): 22.