Effects of short-chain fructooligosaccharides on faecal bifidobacteria and specific immune response in formula-fed term infants: a randomized, double-blind, placebo-controlled trial.

The aim of this study was to evaluate the effect of an infant formula supplemented with short-chain fructooligosaccharides (scFOS) on faecal concentration of bifidobacteria. Sixty-one healthy formula-fed infants participated in this double-blind controlled trial and were randomized to receive either the scFOS-supplemented formula (4 g/L scFOS) or the placebo-supplemented formula (4 g/L maltodextrins) until the age of 4 mo. Stool samples were analyzed for bifidobacteria at enrolment and at the age of 2 and 3 mo and for antipoliovirus IgA at the age of 4 mo. Parents completed a questionnaire to assess digestive tolerance. Change in faecal bifidobacteria after 2 mo were higher with scFOS compared to the placebo. At 4 mo, specific IgA tended to be higher with the scFOS group than with the placebo. Somatic growth and digestive tolerance were similar between groups. This study confirms that scFOS-supplemented formula can increase the concentration of faecal bifidobacteria while being well tolerated.

Incidence of infectious diseases in infants fed follow-on formula containing synbiotics: an observational study.

AIM: Infectious diseases in infants are a major public health issue. Synbiotic-enriched formulas (EF) are intended to mimic the beneficial effects of human milk on infectious diseases. We performed an observational study in infants switching to follow-on formula to determine the effects of synbiotic-enriched formula compared to standard formula (SF). METHODS: We recorded family characteristics, medical history and growth data, as well as the symptoms, severity and treatment of infectious diseases. Main outcome measures were compared after adjustments for baseline characteristics. RESULTS: Between January and June 2007, 771 healthy infants were included in the study; 35.4% experienced at least one infectious disease during the 3-month study period. The most common were upper respiratory tract (24.1%), otitis (6.6%) and gastrointestinal infectious diseases (5.0%). Infants fed synbiotic-enriched formula had fewer infectious diseases overall (EF: 31.0%; SF: 40.6%; p = 0.005) and significantly fewer gastrointestinal infectious diseases (EF: 3.5%; SF: 6.8%; p = 0.03). During follow-up, weight gain was significantly higher (p = 0.0467) in infants fed synbiotic-enriched formula (18.3 ± 8.7 g/day) versus SF (16.9 ± 7.5 g/day). CONCLUSIONS: Supplementation with synbiotics may have beneficial effects on the incidence of infectious disease and growth in infants. Further studies are needed determine optimal doses and composition of synbiotics in infant formula.

Effects of seven potential probiotic strains on specific immune responses in healthy adults: a double-blind, randomized, controlled trial.

This pilot study investigated the immunomodulatory properties of seven probiotic strains. Eighty-three healthy volunteers aged 18-62 years consumed 2 x 10(10) CFU of bacteria or a placebo (maltodextrin) over 3 weeks (D0-D21). Subjects received an oral cholera vaccine at D7 and at D14; blood and saliva samples were collected at D0, D21 and D28. Serum samples were analyzed for specific IgA, IgG and IgM, and saliva samples were analyzed for specific IgA only, by ELISA. Statistical analyses were based on Wilcoxon's signed-rank test (intragroup analyses) and exact median t-test (intergroup analyses). Salivary analysis showed no difference in specific IgA concentrations between groups. Serum analysis indicated an effect of some of the tested strains on specific humoral responses. Between D0 and D21, IgG increased in two probiotic groups, for example, Bifidobacterium lactis Bl-04 and Lactobacillus acidophilus La-14, compared with controls (P=0.01). Trends toward significant changes in immunoglobulin serum concentrations compared with controls (P<0.1) were found for six out of the seven probiotic strains. In conclusion, some strains of probiotics demonstrated a faster immune response measured with serum immunoglobulin indicators, especially IgG, although overall vaccination was not influenced. Specific strains of probiotics may thus act as adjuvants to the humoral immune response following oral vaccination.

Comparison of field methods to estimate fat mass in children.

BACKGROUND: Reliable field methods to measure fat mass (FM) in children may contribute to primary prevention of childhood obesity. AIM: The objective was to compare the accuracy of existing field methods (skinfold thickness (SF), leg-to-leg bioelectrical impedance analysis (BIA), anthropometrics for FM measurement in prepubertal European children. SUBJECTS AND METHODS: Reference FM was measured in 55 French children (30 boys, 25 girls; mean age 8.7 years) using a three-compartment model: body volume (BV) was assessed by air displacement plethysmography (ADP) and total body water (TBW) was assessed by deuterium dilution. Agreement between field methods and the reference method was assessed using Bland-Altman analyses. Since field methods for FM measurement are reported to be population-dependent, adjustment to the study population was performed using stepwise multiple linear regressions modelling. RESULTS: Even after adjustment, field methods exhibited a high correlation (R(2) = 0.71-0.84) but a moderate agreement (+/-3.32 to +/-4.47 kg for fat mass) with the reference model. Methods based on BIA or SF performed slightly better than those based on anthropometry. CONCLUSIONS: Field methods for FM measurement may be recommended for epidemiological applications, but not for individual follow-up. New field equipment is required to improve accuracy of FM measurement in children and make individual follow-up possible.

Family dietary coaching to improve nutritional intakes and body weight control: a randomized controlled trial.

OBJECTIVE: To test the hypothesis that family dietary coaching would improve nutritional intakes and weight control in free-living (noninstitutionalized) children and parents. DESIGN: Randomized controlled trial. SETTING: Fifty-four elementary schools in Paris, France. PARTICIPANTS: One thousand thirteen children (mean age, 7.7 years) and 1013 parents (mean age, 40.5 years). INTERVENTION: Families were randomly assigned to group A (advised to reduce fat and to increase complex carbohydrate intake), group B (advised to reduce both fat and sugar and to increase complex carbohydrate intake), or a control group (given no advice). Groups A and B received monthly phone counseling and Internet-based monitoring for 8 months. OUTCOME MEASURES: Changes in nutritional intake, body mass index (calculated as weight in kilograms divided by height in meters squared), fat mass, physical activity, blood indicators, and quality of life. RESULTS: Compared with controls, participants in the intervention groups achieved their nutritional targets for fat intake and to a smaller extent for sugar and complex carbohydrate intake, leading to a decrease in energy intake (children, P < .001; parents, P = .02). Mean changes in body mass index were similar among children (group A, + 0.05, 95% confidence interval [CI], - 0.06 to 0.16; group B, + 0.10, 95% CI, - 0.03 to 0.23; control group, + 0.13, 95% CI, 0.04-0.22; P = .45), but differed in parents (group A, + 0.13, 95% CI, - 0.01 to 0.27; group B, - 0.02, 95% CI, - 0.14 to 0.11; control group, + 0.24, 95% CI, 0.13-0.34; P = .001), with a significant difference between group B and the control group (P = .01). CONCLUSIONS: Family dietary coaching improves nutritional intake in free-living children and parents, with beneficial effects on weight control in parents. Trial Registration clinicaltrials.gov Identifier: NCT00456911.

The effects of regular consumption of short-chain fructo-oligosaccharides on digestive comfort of subjects with minor functional bowel disorders.

A comparative, randomised, double-blind trial was performed in the medical departments of five hospitals to study the effects of regular consumption of short-chain fructo-oligosaccharides (sc-FOS) on the digestive comfort of subjects with minor functional bowel disorders (FBD). In step 1, 2235 subjects were questioned to assess the incidence and intensity of digestive disorders. In step 2, 105 of these patients diagnosed with minor FBD were randomised into two groups to receive either 5 g sc-FOS or 5 g placebo (sucrose and maltodextrins) per d over a 6-week period. The incidence and intensity of digestive disorders were assessed at the end of the treatment period (day 43) using the step 1 questionnaires. A quality-of-life questionnaire was also completed at the start and end of the treatment period to assess potential effects on well-being and social performance. In step 1, 44 % of the subjects questioned presented FBD, of whom 57.1 % suffered from minor FBD. In step 2, on day 43, the intensity of digestive disorders decreased by 43.6 % in the sc-FOS group v. a 13.8 % increase in the placebo group (P = 0.026). Symptoms were experienced less frequently by 75.0 % of subjects in the sc-FOS group, while 53.8 % of controls experienced no change (P = 0.064). Using the functional digestive disorders quality of life questionnaire, the discomfort item scores increased in the sc-FOS group (P = 0.031). However, expressed as change in quality of life (improvement, worsening or unchanged), daily activities were significantly improved in the sc-FOS group (P = 0.022). Regular consumption of sc-FOS may improve digestive comfort in a working population not undergoing medical treatment.

Four-week short chain fructo-oligosaccharides ingestion leads to increasing fecal bifidobacteria and cholesterol excretion in healthy elderly volunteers.

BACKGROUND: Short-chain fructo-oligosaccharides (scFOS) are increasingly used in human diet for their prebiotic properties. We aimed at investigating the effects of scFOS ingestion on the colonic microflora and oro-fecal transit time in elderly healthy humans. METHODS: Stools composition, oro-fecal transit time, and clinical tolerance were evaluated in 12 healthy volunteers, aged 69 +/- 2 yrs, in three consecutive periods: basal period (2 weeks), scFOS (Actilight) ingestion period (8 g/d for 4 weeks) and follow-up period (4 weeks). Two-way ANOVA, with time and treatment as factors, was used to compare the main outcome measures between the three periods. RESULTS: Fecal bifidobacteria counts were significantly increased during the scFOS period (9.17 +/- 0.17 log cfu/g vs 8.52 +/- 0.26 log cfu/g during the basal period) and returned to their initial values at the end of follow-up (8.37 +/- 0.21 log cfu/g; P < 0.05). Fecal cholesterol concentration increased during the scFOS period (8.18 +/- 2.37 mg/g dry matter vs 2.81 +/- 0.94 mg/g dry matter during the basal period) and returned to the baseline value at the end of follow-up (2.87 +/- 0.44 mg/g dry matter; P < 0.05). Fecal pH tended to decrease during scFOS ingestion and follow-up periods compared to the basal period (P = 0.06). Fecal bile acids, stool weight, water percentage, and oro-fecal transit time did not change throughout the study. Excess flatus and bloating were significantly more frequent during scFOS ingestion when compared to the basal period (P < 0.05), but the intensity of these symptoms was very mild. CONCLUSION: Four-week 8 g/d scFOS ingestion is well tolerated and leads to a significant increase in fecal bifidobacteria in healthy elderly subjects. Whether the change in cholesterol metabolism found in our study could exert a beneficial action warrants further studies.

Glycaemic response to foods: impact on satiety and long-term weight regulation.

Should future nutritional recommendations for the general population take into account the notion of glycaemic index (GI)? This question is all the more legitimate as the glycaemic response to foods seems to be a factor that affects satiety and could therefore affect food intake. The aim of this review was to evaluate whether altering the glycaemic response per se can modulate satiety and to assess the short-term and long-term consequences. A systematic review of human intervention studies was performed. Confounding factors that may influence both GI and satiety were taken into consideration when selecting the studies. Thirty-two studies were thus selected and analysed. There is evidence from the short-term studies (1 day) that low-glycaemic foods or meals have higher satietogenic effect than high-glycaemic foods or meals. This substantiates claims such as 'low-GI foods help one to feel fuller for longer than equivalent high-GI foods'. The mechanisms involved may be the specific effect of blood glucose levels on satiety (glucostatic theory) and other stimuli (e.g. peptides) involved in the control of appetite. In some studies, however it seems difficult to tease out the separate effect of the lowering of postprandial glycaemia per se and fibres. Because of the increasing number of confounding variables in the available long-term studies, it is not possible to conclude that low-glycaemic diets mediate a health benefit based on body weight regulation. The difficulty of demonstrating the long-term health benefit of a satietogenic food or diet may constitute an obstacle to the recognition of associated claims.

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 (r2 = 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.

Influence of short-chain fructo-oligosaccharides (sc-FOS) on absorption of Cu, Zn, and Se in healthy postmenopausal women.

OBJECTIVE: This study was carried out to evaluate the effect of short-chain fructooligosaccharides (sc-FOS) on the absorption of Cu, Zn, and Se among postmenopausal women who are potential candidates to subclinical trace element deficiencies. DESIGN: A randomized double blind cross-over study. SETTING: This study was carried out at the Human Nutrition Research Center, Clermont-Ferrand, France. SUBJECTS: 11 postmenopausal women aged 53-70 y, not taking hormone replacement therapy were enrolled and completed the study. INTERVENTIONS: Diets with 10 g/day sc-FOS or placebo were given for 5 weeks each in random order followed by a wash-out period of at least 3 weeks. At the end of each period, stable isotopes (3.19 mg 67Zn as ZnCl2, 2.06 mg 65Cu as CuCl2 and 52.3 microg 74Se as sodium selenite) and radiopaque pellets (as fecal excretion index) were administered during lunch. Stools were collected for the next 5-7 days. Isotopes were determined by ICP-MS (Cu and Zn) or GC-MS (Se). RESULTS: Copper absorption was significantly enhanced (p = 0.042) by sc-FOS. No effect of sc-FOS was observed on Zn, and Se absorption. CONCLUSION: To our knowledge, this is the first study on the influence of sc-FOS on trace element metabolism. The observed increase in copper absorption may be of interest regarding daily copper requirements in menopausal women. However, the relevance of this observation remains to be established.

Effects of a 3-mo consumption of short-chain fructo-oligosaccharides on parameters of colorectal carcinogenesis in patients with or without small or large colorectal adenomas.

Intervention studies of colorectal adenoma recurrence have demonstrated the need for surrogate markers of the cancer risk. Short-chain fructo-oligosaccharides (sc-FOS) have protective actions on colon carcinogenesis in animal models. We investigated differences in biological markers between adenoma and adenoma-free subjects, before and after 3 mo of daily intake of 10 g sc-FOS, within a multicenter study. After a full colonoscopy, 3 groups were studied at baseline and after 3 mo: 26 subjects with small colorectal adenoma(s), 18 with large adenoma(s), and 30 with no adenoma. At baseline, the mean fecal butyrate concentration was significantly lower in the adenoma groups than in the adenoma-free group (12.01 +/- 5.08 vs. 17.28 +/- 7.34 mmol/g dry weight) but was significantly increased in that group after 3-mo ingestion of sc-FOS (15.7 +/- 8.0 mmol/g; P = 0.02). In subjects without adenoma, sc-FOS ingestion was associated with a decrease in fecal lithocholic acid (P = 0.02) and an increase in cholic acid (P = 0.02), chenodeoxycholic acid (P = 0.04), total primary bile acids (P = 0.03), and ursodeoxycholic acid (P = 0.05). Fecal pH, blood parameters, and crypt cell proliferation were not significantly modified by sc-FOS ingestion in either group. In subjects with and without adenoma, sc-FOS affects some aspects of the colonic environment, which may be involved in prevention of colorectal neoplasia.

The capacity of nondigestible carbohydrates to stimulate fecal bifidobacteria in healthy humans: a double-blind, randomized, placebo-controlled, parallel-group, dose-response relation study.

BACKGROUND: Nondigestible carbohydrates (NDCHs) are fermented in the colon, where they can selectively promote the growth of bifidobacteria. OBJECTIVE: Our aim was to determine the bifidogenic potential of different NDCHs used in human diets. DESIGN: Two hundred healthy volunteers participated in this double-blind study. During phase 1 (screening), 64 volunteers were randomly assigned to 8 groups of 8 subjects each; for 7 d, they ingested 10 g/d of 1 of the 7 NDCHs tested or of the placebo. During phase 2 (dose-response study), 136 volunteers were randomly assigned to 4 groups of 32 subjects who received 2.5, 5.0, 7.5, or 10 g/d, respectively (8 subjects/dose), of one of the NDCHs that were proven to be bifidogenic during phase 1 and a fifth group of 8 subjects (control subjects) who received the placebo. Stools were recovered before and after NDCH consumption. RESULTS: In phase 1, 4 NDCHs were found to be bifidogenic: short-chain fructooligosaccharides (P=0.008), soybean oligosaccharides (P=0.006), galactooligosaccharides (P <0.0001), and type III resistant starch (P=0.02); lactulose, long-chain inulin, and isomaltooligosaccharides were not bifidogenic. In phase 2, the effects of 7-d treatment on bifidobacteria concentrations were found to differ significantly among the 4 NDCHs (P=0.009 for time x treatment interaction). However, no significant differences were found among doses, and there was no significant dose x time interaction. A low baseline bifidobacteria count was significantly associated with the bifidogenic response to treatment (P <0.001). CONCLUSION: This study showed the different bifidogenic properties among the substrates and underlined the importance of taking into account the baseline bifidobacteria counts when evaluating the effect of the treatment.

Effect of short-chain fructooligosaccharides on intestinal calcium absorption and calcium status in postmenopausal women: a stable-isotope study.

BACKGROUND: An enhancing effect of short-chain fructooligosaccharides (scFOSs) on intestinal calcium absorption has been shown in animals and in some short-term human studies. However, the long-term effect of scFOSs on calcium absorption in humans is still unknown. OBJECTIVE: We investigated the long-term effect of a moderate daily dose (10 g) of scFOSs on intestinal calcium absorption in postmenopausal women. DESIGN: In a randomized, double-blind crossover protocol, 12 healthy, postmenopausal women received scFOSs or placebo for 5 wk. The treatments were separated by a 3-wk washout period. Subjects orally received (44)Ca (stable isotope) and a fecal marker. Feces were collected after the isotope intake for 5-7 d to measure unabsorbed isotope. Calcium-status indexes, calciotropic hormones, and bone turnover were also assessed. RESULTS: Mean (+/-SD) intestinal calcium absorption with scFOS treatment was not significantly different from that with placebo treatment (35.63 +/- 9.40% and 36.55 +/- 8.48%, respectively). However, a tendency for calcium absorption to be higher with scFOS treatment than with placebo treatment was observed in women who had been going through menopause for >6 y. CONCLUSIONS: scFOSs do not modify intestinal calcium absorption in postmenopausal women who do not receive hormonal replacement therapy. The results from a subgroup of women who had been going through menopause for >6 y (n = 6) suggest that scFOSs may influence calcium absorption in the late postmenopausal phase. The small number of subjects and the related P value warrant verification and further investigation with women in late menopause only.

Immune-stimulating and gut health-promoting properties of short-chain fructo-oligosaccharides.

Short-chain fructo-oligosaccharides are a group of linear fructose oligomers with a degree of polymerization ranging from one up to five (oligosaccharides). Recent observations in animal models demonstrate that prebiotics and probiotics may exert beneficial effects on gut health by enhancing gut-associated lymphoid tissue responses either directly or indirectly through the production of short-chain fatty acids and the enhanced growth of lactic bacteria such as bifidobacteria and lactobacilli. Demonstration of the potential health benefits of short-chain fructooligosaccharides on colon cancer risk is an active field of research in animal and human nutrition.