High-fiber oat cereal compared with wheat cereal consumption favorably alters LDL-cholesterol subclass and particle numbers in middle-aged and older men.
BACKGROUND
No studies have examined whether increased consumption of oat cereal, rich in soluble fiber, favorably alters lipoprotein particle size and number.


OBJECTIVE
We examined the effects of large servings of either oat or wheat cereal on plasma lipids, lipoprotein subclasses, lipoprotein particle diameters, and LDL particle number.


METHODS
Thirty-six overweight men aged 50-75 y were randomly assigned to consume daily for 12 wk either oat or wheat cereal providing 14 g dietary fiber/d. Before and after the intervention, plasma lipid and lipoprotein subclasses were measured with proton nuclear magnetic resonance spectroscopy, and whole-body insulin sensitivity was estimated with the frequently sampled intravenous-glucose-tolerance test.


RESULTS
Time-by-treatment interactions (P < 0.05) for LDL cholesterol (oat: -2.5%; wheat: 8.0%), small LDL cholesterol (oat: -17.3%; wheat: 60.4%), LDL particle number (oat: -5.0%; wheat: 14.2%), and LDL:HDL cholesterol (oat: -6.3%; wheat: 14.2%) were observed. Time-by-treatment interactions were nearly significant for total cholesterol (oat: -2.5%; wheat: 6.3%; P = 0.08), triacylglycerol (oat: -6.6%; wheat: 22.0%; P = 0.07), and VLDL triacylglycerol (oat: -7.6%; wheat: 2.7%; P = 0.08). No significant time-by-treatment interactions were observed for HDL cholesterol, HDL-cholesterol subclasses, or LDL, HDL, and VLDL particle diameters. Insulin sensitivity did not change significantly with either intervention.


CONCLUSIONS
The oat compared with the wheat cereal produced lower concentrations of small, dense LDL cholesterol and LDL particle number without producing adverse changes in blood triacylglycerol or HDL-cholesterol concentrations. These beneficial alterations may contribute to the cardioprotective effect of oat fiber.
Davy
Brenda M
BM
Department of Food Science and Human Nutrition, Colorado State University, Fort Collins 80523, USA.
Davy
Kevin P
KP
Ho
Richard C
RC
Beske
Stacy D
SD
Davrath
Linda R
LR
Melby
Christopher L
CL
D000368:Aged; D018554:Avena; D008078:Cholesterol, LDL / Q000097:blood*; D004032:Diet; D004043:Dietary Fiber / Q000008:administration & dosage / Q000494:pharmacology*; D002523:Edible Grain; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood; D014908:Triticum
D008078:Cholesterol, LDL; D004043:Dietary Fiber; D014280:Triglycerides; D005947:Glucose