Specific types of colonic fermentation may raise low-density-lipoprotein-cholesterol concentrations.
To assess the effects of increased colonic fermentation on serum lipids, eight healthy volunteers were placed on two identical 2-wk metabolic diets, one of which was supplemented with lactulose (18-25 g/d). Lactulose raised day-long concentrations of breath hydrogen and serum glutamine as indicators of increased colonic fermentation by 78 +/- 13% (P less than 0.001) and 24.7 +/- 9.5% (P less than 0.05), respectively). Unexpectedly, however, fasting serum total and low-density-lipoprotein cholesterol and apolipoprotein B concentrations were higher at 2 wk by 8.9 +/- 1.5% (P less than 0.001), 10.9 +/- 2.2% (P less than 0.005), and 18.9 +/- 5.9% (P less than 0.02), respectively, compared with the control diet. With lactulose, mean free fatty acid concentrations were reduced over the day by 19.5 +/- 5.9% (P less than 0.02), with no change in mean day-long blood glucose, serum insulin, or C-peptide concentrations. We conclude that certain rapidly fermented substrates may raise rather than lower serum lipids, possibly through increasing the amount of acetate absorbed from the colon.
Jenkins
D J
DJ
Department of Nutritional Science, Faculty of Medicine, St Michael's Hospital, University of Toronto, Ontario, Canada.
Wolever
T M
TM
Jenkins
A
A
Brighenti
F
F
Vuksan
V
V
Rao
A V
AV
Cunnane
S C
SC
Ocana
A
A
Corey
P
P
Vezina
C
C
D000085:Acetates / Q000097:blood; D000328:Adult; D001055:Apolipoproteins B / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D001944:Breath Tests; D008078:Cholesterol, LDL / Q000097:blood*; D003106:Colon / Q000378:metabolism*; D015930:Diet Records; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005285:Fermentation; D005973:Glutamine / Q000097:blood; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007328:Insulin / Q000097:blood; D007792:Lactulose / Q000008:administration & dosage; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood
D000085:Acetates; D001055:Apolipoproteins B; D001786:Blood Glucose; D008078:Cholesterol, LDL; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D008055:Lipids; D014280:Triglycerides; D005973:Glutamine; D007792:Lactulose; D006859:Hydrogen