Effect of consumption of a ready-to-eat breakfast cereal containing inulin on the intestinal milieu and blood lipids in healthy male volunteers.
OBJECTIVE
To investigate the effect of a breakfast cereal containing inulin on blood lipids and colonic ecosystem in normolipidemic young men.


METHODS
Department of Food Science and Microbiology,University of Milan, Italy.


METHODS
Twelve healthy male volunteers, age 23.3 +/- 0.5 y, body mass index (BMI) 25.7 +/- 1.2 kg/m2 (mean +/- s.e.m.).


METHODS
Subjects consumed daily, for three periods of four weeks, 50 g of a rice-based ready-to-eat cereal (placebo) and the same cereal containing 18% inulin (test) in substitution of their habitual breakfast, then returned to the habitual diet (wash-out). They followed no other dietary restrictions.


RESULTS
No changes in body weight, dietary habits, faecal and bile acid output, faecal short-chain fatty acid (SCFA) and faecal pH, were observed at the end of each period, whereas plasma total cholesterol and triacylglycerols significantly decreased at the end of test period by 7.9 +/- 5.4 (P < 0.05) and 21.2 +/- 7.8% (P < 0.005) respectively. Meal glucose tolerance test (MTT) resulted in the same incremental area under the curve for both cereals (IAUC test 124 +/- 35; placebo 118 +/- 33 mmol x min/l, ns). Inulin markedly enhanced breath H2 excretion (IAUC test 280 +/- 40; placebo 78 +/- 26 ppm x h, P < 0.005), as well as faecal concentration of L-lactate. Total facultative anaerobes significantly decreased after test, and bifidobacteria increased after correction for total anaerobes (P < 0.05). Changes in blood lipids were negatively correlated with bifidobacteria counts and positively with secondary bile acid excretion (P < 0.05).


CONCLUSIONS
Inulin seems to have a lipid lowering potential in normolipidemic men possibly mediated by mechanisms related to colonic fermentation.
Brighenti
F
F
Department of Food Science, Technology and Microbiology, University of Milan, Italy. furio.brighenti@unimi.it
Casiraghi
M C
MC
Canzi
E
E
Ferrari
A
A
D000328:Adult; D000704:Analysis of Variance; D001647:Bile Acids and Salts / Q000378:metabolism; D003106:Colon / Q000382:microbiology; D002523:Edible Grain; D002149:Energy Intake; D005243:Feces / Q000382:microbiology; D005260:Female; D005285:Fermentation; D005951:Glucose Tolerance Test; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects*; D007444:Inulin / Q000008:administration & dosage / Q000494:pharmacology*; D007558:Italy; D008055:Lipids / Q000097:blood*; D008297:Male
D001647:Bile Acids and Salts; D008055:Lipids; D007444:Inulin