Bifidobacterium animalis strain DN-173 010 shortens the colonic transit time in healthy women: a double-blind, randomized, controlled study.

BACKGROUND: A previous study has suggested that Bifidobacterium animalis DN-173 010 shortens the colonic transit time in women. AIM: To confirm this effect and to determine whether modifications of the faecal bacterial mass and/or faecal secondary bile salts may be the explanation. METHODS: A double-blind, cross-over study was performed. Thirty-six healthy women were studied in four consecutive 10-day periods. During periods 2 and 4, they ingested three 125 g cups per day of a fermented milk which was either a product containing B. animalis DN-173 010 or a control without bifidobacteria. Periods 1 and 3 were run-in and washout periods, respectively. The total and segmental colonic transit times were assessed using a pellet method. In 12 subjects, all stools were collected and analysed for pH, faecal weight, bacterial mass and bile acids. RESULTS: The total and sigmoid transit times were significantly shorter during dosing with B. animalis compared to the control period. The other transit times, faecal weight, pH, bacterial mass and bile acids were not significantly affected. CONCLUSIONS: B. animalis DN-173 010 shortens the colonic transit time in healthy women. This effect is not explained by modifications of the faecal bacterial mass or secondary bile acids.

Energy intake, body mass index, physical activity, and the colorectal adenoma-carcinoma sequence.

Little is known about the precise relationship between energy intake, overweight, sedentary lifestyle, and steps in the colorectal adenoma-carcinoma pathway. We studied these parameters within a case-control study. Patients with adenomas < 10 mm (n = 154) or > 10 mm (n = 208) were compared with polyp-free controls (n = 426) for determining factors associated with adenoma formation, i.e., observed for small and large adenomas, or with adenoma growth only. Colorectal cancer cases (n = 171) were compared with population controls (n = 309) to determine factors specific to the final stage, cancer. Exercise reduced the risk of cancer [odds ratio (OR) = 0.3, 95% confidence interval (CI) = 0.2-0.5 for high vs. low physical activity] but had little influence on adenomas. High energy intake increased the risk of cancer [OR for 5th vs. 1st quintile (OR5) = 1.6, 95% CI = 0.9-2.9, p = 0.02], but not of adenomas. High body mass index (BMI) significantly increased the risk of large adenomas (OR5 = 2.1, 95% CI = 1.2-3.5, p = 0.02 and OR5 = 1.7, 95% CI = 1.0-3.1, p = 0.25) for large and small adenomas vs. polyp-free controls. Neither height nor weight nor BMI influenced the risk of cancer. Results were unmodified when controlling for dietary risk factors and family history. Energy intake, a sedentary lifestyle, and high BMI were independently associated with a high risk of cancer itself or large adenomas, which indicates an effect on promotion of colorectal tumors. These findings suggest that preventive advice regarding these factors should be provided, even late in life, to decrease the risk of colorectal cancer.

Comparison of gastric emptying of a solid and a liquid nutritional rehabilitation food.

OBJECTIVE: To compare gastric emptying of a solid and a liquid nutritional rehabilitation food. DESIGN: Cross-over trial. Eight volunteers took, in random order at least 1 week apart, 2100 kJ of a solid and a liquid nutritional rehabilitation food with added labelled [13C] glycine. SETTING: Research ward for healthy volunteers. SUBJECTS: Eight healthy volunteers. METHODS: Appearance of 13CO2 was monitored in expired gas every 15 min for 240 min after meal intake and compared between solid and liquid meals. Parameters of gastric emptying were then calculated. RESULTS: Gastric half-emptying time was slightly longer for solid meal compared to liquid meal (101+/-6.0 vs 88+/-9.8 min, P=0.24). 13CO2 excretion peaked 138+/-5.3 min after the solid meal compared with 119+/-8.6 min with liquid meal (P=0.06). 13CO2 excretion was higher for the liquid food up to 110 min after the meal but then became higher for the solid food. Analysis of variance for repeated measures of 13CO2 excretion showed a significant interaction term between the type of food and time indicating a delayed elimination of 13CO2 for the solid food (P=0.018). CONCLUSIONS: Attempts to replace liquid nutritional rehabilitation foods by a solid food in malnourished patients should take into account a possible slower gastric emptying. SPONSORSHIP: Supported by a grant from Nutriset (Malaunay, France) and ANVAR (Agence Nationale de la Valorisation de la Recherche, contract no. A9703021P).

Comparison of starch digestibility of a blended food prepared with and without extrusion cooking.

OBJECTIVE: To compare starch digestibility from a maize-soy blended food with and without extrusion cooking. DESIGN: Resistant starch, soluble and insoluble dietary fibres were measured in vitro before and after extrusion. Starch digestibility was assessed in 8 volunteers who took, in a randomised order, a test meal with either 100 g extruded (EF) or non-extruded (NEF) blended flour cooked 15 min at 80 degrees C in 500 ml of water. SETTING: Research ward for healthy volunteers. SUBJECTS: Healthy volunteers. MAIN OUTCOME MEASURES: Starch digestibility was measured by 13C enrichment of breath samples for 8 h. Breath H2 concentration was measured during 12 h to assess bacterial fermentation in the colon. Volunteers reported hunger on a visual scale every hour for 8 h. RESULTS: In vitro resistant starch, soluble and insoluble dietary fibers were higher in NEF than in EF (5.4 vs 1.1, 0.7 vs 0.5, and 13.3 vs 10.4% dw respectively). In vivo, the area under curve (AUC) for 13CO2 excretion during 8 h was not significantly different for NEF and EF (10.3+/-1.3 vs 9.1+/-0.5 mmol/min, respectively). AUC for H2 excretion during 12 h was significantly higher for EF than for NEF (26.9+/-5.6 vs 14.1+/-4.7 mL, P<0.05). AUC for satiety was marginally higher with EF (12.6+/-1.6) than for NEF (10.0+/-2.1) (P=0.06). CONCLUSIONS: Extrusion cooking does not seem to substantially improve blended foods digestibility. Extrusion of high fibre flours may promote carbohydrate fermentation in the colon and increase satiety.

Foods as risk factors for colorectal cancer: a case-control study in Burgundy (France).

Although the high meat-low vegetable diet is considered the reference high-risk diet for colorectal cancer, particularly in USA communities, other at-risk dietary patterns, such as high intakes of processed meat and refined carbohydrates are emerging. Little is known about risk factors for colorectal cancer in France, a country at high risk of rectal cancer and moderately high risk of colon cancer. We compared diet of colorectal cancer cases (n = 171) and general population controls (n = 309) in Burgundy (France). Categories of intake were established by sex and based on the distributions of food intakes in controls. Odds ratios for the fourth vs first quartile of intake (OR4) were 2.0 (1.1-3.6) for refined cereal products (rice, pasta and pastry), 2.4 (1.3-4.5) for delicatessen, 2.3 (1.2-4.2) for patés, 1.7 (1.1-2.8) for offal and 2.1 (1.1-4.0) for butter, lard and cream. There was no association with consumption of fresh meat (OR4 = 1.2), fish (OR4 = 1.5), egg (OR4 = 1.1) or dairy products (OR4 = 1.0). A protective effect of vegetables was only observed for left colon cancer (OR3 = 0.3; 0.1-0.6). In men, the most significant risk factors were refined cereal products, seasoning animal fats, chocolate and coffee, whereas risk factors were delicatessen, fat meat, pasta, rice, and chocolate in women. The strong association with refined cereal products is consistent with the hypothesis of a role of hyperinsulinism in colorectal carcinogenesis. The association with processed but not fresh meat suggests the importance of exogenous carcinogenesis in that area.