Modest doses of beta-glucan do not reduce concentrations of potentially atherogenic lipoproteins.
BACKGROUND
In 1997, the US Food and Drug Administration passed a unique ruling that allowed oat bran to be registered as the first cholesterol-reducing food at a dosage of 3 g beta-glucan/d.


OBJECTIVE
The effects of a low dose of oat bran in the background diet only were investigated in volunteers with mild-to-moderate hyperlipidemia.


METHODS
The study was a double-blind, placebo-controlled, randomized, parallel study. Sixty-two healthy men (n = 31) and women (n = 31) were randomly allocated to consume either 20 g oat bran concentrate (OBC; containing 3 g beta-glucan) or 20 g wheat bran (control) daily for 8 wk. Fasting blood samples were collected at weeks -1, 0, 4, 8, and 12. A subgroup (n = 17) was studied postprandially after consumption of 2 meals (containing no OBC or wheat bran) at baseline and after supplementation. Fasting plasma samples were analyzed for total cholesterol, HDL cholesterol, triacylglycerol, glucose, and insulin. LDL cholesterol was measured by using the Friedewald formula. The postprandial samples were anlayzed for triacylglycerol, glucose, and insulin.


RESULTS
No significant difference was observed in fasting plasma cholesterol, LDL cholesterol, glucose, or insulin between the OBC and wheat-bran groups. HDL-cholesterol concentrations fell significantly from weeks 0 to 8 in the OBC group (P = 0.05). There was a significant increase in fasting glucose concentrations after both OBC (P = 0.03) and wheat-bran (P = 0.02) consumption. No significant difference was found between the OBC and wheat-bran groups in any of the postprandial variables measured.


CONCLUSIONS
A low dosage of beta-glucan (3 g/d) did not significantly reduce total cholesterol or LDL cholesterol in volunteers with plasma cholesterol concentrations representative of a middle-aged UK population.
Lovegrove
J A
JA
Hugh Sinclair Unit of Human Nutrition, The University of Reading, Reading, United Kingdom, and Nestlé, Vivey, Switzerland. j.a.lovegrove@afnovell.reading.ac.uk
Clohessy
A
A
Milon
H
H
Williams
C M
CM
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004032:Diet; D004311:Double-Blind Method; D005260:Female; D005936:Glucans / Q000008:administration & dosage*; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood* / Q000178:diet therapy; D007328:Insulin / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D005936:Glucans; D007328:Insulin; D008074:Lipoproteins; D014280:Triglycerides