Differential effects of FODMAPs (Fermentable Oligo-, Di-, Mono-Saccharides and Polyols) on small and large intestinal contents in healthy subjects shown by MRI

OBJECTIVES: The objective of this study was to investigate whether ingestion of fructose and fructans (such as inulin) can exacerbate irritable bowel syndrome (IBS) symptoms. The aim was to better understand the origin of these symptoms by magnetic resonance imaging (MRI) of the gut. METHODS: A total of 16 healthy volunteers participated in a four-way, randomized, single-blind, crossover study in which they consumed 500 ml of water containing 40 g of either glucose, fructose, inulin, or a 1:1 mixture of 40 g glucose and 40 g fructose. MRI scans were performed hourly for 5 h, assessing the volume of gastric contents, small bowel water content (SBWC), and colonic gas. Breath hydrogen (H 2) was measured and symptoms recorded after each scan. RESULTS: Data are reported as mean (s.d.) (95 % CI) when normally distributed and median (range) when not. Fructose increased area under the curve (AUC) from 0 – 5 h of SBWC to 71 (23) l / min, significantly greater than for glucose at 36 (11 – 132) l / min ( P < 0.001), whereas AUC SBWC after inulin, 33 (17 – 106) l / min, was no different from that after glucose. Adding glucose to fructose decreased AUC SBWC to 55 (28) l / min ( P = 0.08) vs. fructose. Inulin substantially increased AUC colonic gas to 33 (20) l / min, signifi cantly greater than glucose and glucose + fructose (both P < 0.05). Breath H 2 rose more with inulin than with fructose. Glucose when combined with fructose signifi cantly reduced breath H 2 by 7,700 (3,121 – 12,300) p.p.m. / min relative to fructose alone ( P < 0.01, n = 13). CONCLUSIONS: Fructose but not inulin distends the small bowel with water. Adding glucose to fructose reduces the effect of fructose on SBWC and breath hydrogen. Inulin distends the colon with gas more than fructose, but causes few symptoms in healthy volunteers

Effect of a prebiotic galactooligosaccharide mixture (B-GOS®) on gastrointestinal symptoms in adults selected from a general population who suffer with bloating, abdominal pain, or flatulence

Background Prebiotics exert beneficial effects upon gastrointestinal (GI) environment, but this is not always accompanied with a positive effect on GI symptoms. B‐GOS® is a prebiotic with high selectivity toward bifidobacteria and a variety of other beneficial effects in humans. Here, we investigated its effect on GI symptoms in adults who suffer with bloating, abdominal pain, and flatulence. Methods In a double‐blind, placebo‐controlled, crossover study, 83 subjects from the general population who presented with GI symptoms during screening period and had a predicted probability of functional bowel disorder of more than 75% were randomized to receive either a placebo or the B‐GOS® treatment (2.75 g/d). Subjects were screened for the presence of GI symptoms for 1 week, they consumed the treatments for 2 weeks, and then went through a 2‐week washout period, before switching to the other treatment for the final 2 weeks. GI symptoms, bowel movements, and stool consistency were assessed in daily and weekly questionnaires. Quality of life was assessed weekly and depression and anxiety at the end of each treatment period. Results B‐GOS® resulted in significantly (P < 0.001) lower scores for bloating, flatulence, and abdominal pain both from baseline and placebo at the end of first week. The effect was sustained at the end of second week. It had no effect on the number of bowel movements, consistency of stools, quality of life, or mood throughout the study. Conclusion Results suggest that B‐GOS® could possibly be used in the management of bloating, flatulence, or abdominal pain and warrant further investigation

Investigating the effects of an oral fructose challenge on hepatic ATP reserves in healthy volunteers: a 31P MRS study

Background: Impaired homeostasis of hepatic ATP has been associated with NAFLD. An intravenous fructose infusion has been shown to be an effective challenge to monitor the depletion and subsequent recovery of hepatic ATP reserves using 31P MRS. Aims: The purpose of this study was to evaluate the effects of an oral rather than intravenous fructose challenge on hepatic ATP reserves in healthy subjects. Methods: Self-reported healthy males were recruited. Following an overnight fast, baseline liver glycogen and lipid levels were measured using Magnetic Resonance Spectroscopy (MRS). Immediately after consuming a 500 ml 75 g fructose drink (1275 kJ) subjects were scanned continuously for 90 min to acquire dynamic 31P MRS measurements of liver ATP reserves. Results: A significant effect on ATP reserves was observed across the time course (P < 0.05). Mean ATP levels reached a minimum at 50 min which was markedly lower than baseline (80 ± 17% baseline, P < 0.05). Subsequently, mean values tended to rise but did not reach statistical significance above minimum. The time to minimum ATP levels across subjects was negatively correlated with BMI (R2 ¼ 0.74, P < 0.005). Rates of ATP recovery were not significantly correlated with BMI or liver fat levels, but were negatively correlated with baseline glycogen levels (R2 ¼ 0.7, P < 0.05). Conclusions: Depletion of ATP reserves can be measured non-invasively following an oral fructose challenge using 31P

Whole grain-rich diet reduces body weight and systemic low-grade inflammation without inducing major changes of the gut microbiome: a randomised cross-over trial

Objective To investigate whether a whole grain diet alters the gut microbiome and insulin sensitivity, as well as biomarkers of metabolic health and gut functionality. Design 60 Danish adults at risk of developing metabolic syndrome were included in a randomised cross-over trial with two 8-week dietary intervention periods comprising whole grain diet and refined grain diet, separated by a washout period of ≥6 weeks. The response to the interventions on the gut microbiome composition and insulin sensitivity as well on measures of glucose and lipid metabolism, gut functionality, inflammatory markers, anthropometry and urine metabolomics were assessed. Results 50 participants completed both periods with a whole grain intake of 179±50 g/day and 13±10 g/day in the whole grain and refined grain period, respectively. Compliance was confirmed by a difference in plasma alkylresorcinols (p&lt;0.0001). Compared with refined grain, whole grain did not significantly alter glucose homeostasis and did not induce major changes in the faecal microbiome. Also, breath hydrogen levels, plasma short-chain fatty acids, intestinal integrity and intestinal transit time were not affected. The whole grain diet did, however, compared with the refined grain diet, decrease body weight (p&lt;0.0001), serum inflammatory markers, interleukin (IL)-6 (p=0.009) and C-reactive protein (p=0.003). The reduction in body weight was consistent with a reduction in energy intake, and IL-6 reduction was associated with the amount of whole grain consumed, in particular with intake of rye. Conclusion Compared with refined grain diet, whole grain diet did not alter insulin sensitivity and gut microbiome but reduced body weight and systemic low-grade inflammation

The capacity of short-chain fructo-oligosaccharides to stimulate faecal bifidobacteria: a dose-response relationship study in healthy humans

BACKGROUND: Short-chain fructo-oligosaccharides (scFOS) are well-known for their bifidogenicity. In a large study comprising 200 healthy volunteers, we determined the bifidogenic properties of 7 non-digestible carbohydrates administered at a dose of 10 g/d in the diet; we analysed dose-response relationships of the bifidogenic substrates at doses ranging from 2.5 to 10 g/d in comparison with a placebo. The aim of this presentation is to give more details about the dose-response effects of short-chain fructo-oligosaccharides (scFOS). METHODS: Forty healthy volunteers (18 males, 22 females) eating their usual diets were randomly divided into 5 groups of 8 subjects and received scFOS at a dose of 2.5, 5.0, 7.5 and 10 g/d or a placebo for 7 d. Stools were collected before (day (d) 8) and at the end (day (d) 15) of sugar consumption, and tolerance was evaluated using a daily chart. RESULTS (M ± SEM): Bifidobacteria counts increase was higher in scFOS than in placebo group for all doses tested [2.5 g/d (from 9.15 ± 0.59 to 9.39 ± 0.70; P = 0.02); 5 g/d (from 10.21 ± 0.21 to 10.67 ± 0.22; P = 0.03); 7.5 g/d (from 9.28 ± 0.49 to 9.85 ± 0.35;P = 0.01); 10 g/d (from 9.00 ± 0.81 to 10.18 ± 0.60; P = 0.003)]. A significant correlation between the ingested dose of scFOS and faecal bifidobacteria counts was observed at d15 (r(2 )= 0.307, P < 0.001). Total anaerobes increased at the dose of 10 g/d. No significant differences were found for Bacteroides, Lactobacillus, enterobacteria or pH in any group. The frequency of digestive symptoms was not different between scFOS at any of the doses tested and placebo. Bloating was significantly more intense during scFOS ingestion at doses of 2.5 and 5 g/d, but not at doses of 7.5 and 10 g/d. Excess flatus, borborygmi and abdominal pain did not differ from the placebo at any of the doses tested. CONCLUSION: This study showed that scFOS is bifidogenic and well tolerated at doses ranging from 2.5 to 10 g/d, and that there is a dose-response relationship in healthy volunteers

Electroesophagogram in gastroesophageal reflux disease with a new theory on the pathogenesis of its electric changes

BACKGROUND: In view of the disturbed esophageal peristaltic activity and abnormal esophageal motility in gastroesophageal reflux disease, (GERD), we investigated the hypothesis that these changes result from a disordered myoelectric activity of the esophagus. METHODS: The electric activity of the esophagus (electroesophagogram, EEG) was studied in 27 patients with GERD (16 men, 11 women, mean age 42.6 ± 5.2 years) and 10 healthy volunteers as controls (6 men, 4 women, mean age 41.4 ± 4.9 years). According to the Feussner scoring system, 7 patients had a mild (score 1), 10 a moderate (score 2) and 10 a severe (score 3) stage of the disease. One electrode was applied to the upper third and a second to the lower third of the esophagus, and the electric activity was recorded. The test was repeated after the upper electrode had been moved to the mid-esophagus. RESULTS: The EEG of the healthy volunteers showed slow waves and exhibited the same frequency, amplitude and conduction velocity from the 2 electrodes of the individual subject, regardless of their location in the upper, middle or lower esophagus. Action potentials occurred randomly. In GERD patients, score 1 exhibited electric waves' variables similar to those of the healthy volunteers. In score 2, the waves recorded irregular rhythm and lower variables than the controls. Score 3 showed a "silent" EEG without waves. CONCLUSION: The electric activity in GERD exhibited 3 different patterns depending on the stages of GERD. Score 1 exhibited a normal EEG which apparently denotes normal esophageal motility. Score 2 recorded irregular electric waves variables which are presumably indicative of decreased esophageal motility and reflux clearance. In score 3, a "silent" EEG was recorded with probably no acid clearance. It is postulated that the interstitial cells of Cajal which are the electric activity generators, are involved in the inflammatory process of GERD. Destruction of these cells appears to occur in grades that are in accordance with GERD scores. The EEG seems to have the potential to act as an investigative tool in the diagnosis of GERD stages