Addition of guar gum and soy protein increases the efficacy of the American Heart Association (AHA) step I cholesterol-lowering diet without reducing high density lipoprotein cholesterol levels in non-human primates.
The aim of this study was to determine whether the addition of soy protein and guar gum to the American Heart Association (AHA) Step I diet would increase its efficacy compared with the typical "Average American Diet" (AAD) in a non-human primate model. Twenty adult female cynomolgus monkeys (Macaca fascicularis) were fed one of three diets for 6 wk. The AAD contained 36% energy from fat; the standard Step I diet contained 30% energy from fat; and the modified AHA Step I diet contained 30% energy from fat with the addition of soy protein isolate (10% of total energy) and guar gum (5.8 g/d). Plasma samples were collected from food-deprived monkeys at 4, 5 and 6 wk of dietary treatment for analyses of plasma total cholesterol (TC), lipoprotein cholesterol and triacylglycerol (TAG) concentrations. Plasma TC, LDL-C, HDL-C and TAG concentrations were not significantly different in wk 4, 5 and 6 within any of the diet periods; thus the three measurements were averaged. After 6 wk of dietary treatment, monkeys fed the standard Step I diet had lower plasma TC (-19%) (P < 0.05) and LDL cholesterol (LDL-C) (-24%) (P < 0.09) than when they were fed the AAD, with no effect on HDL cholesterol (HDL-C), the lipoprotein cholesterol profile or TAG. Beyond the effect of the standard Step I diet, the modified AHA Step I diet further reduced plasma TC and LDL-C (-24% and -40%) (P < 0. 05) and the TC/HDL-C and LDL-C/HDL-C ratios (-37% and -52%) (P < 0. 05) with no significant changes in plasma HDL-C or TAG. The primary conclusions of this study are that the efficacy of the AHA Step I cholesterol-lowering diet can be increased with the addition of soy protein and guar gum and provide a more favorable lipoprotein cholesterol profile. Whether the cholesterol-lowering effect is the result of soy protein or guar gum or a synergistic effect of both remains to be determined.
Wilson
T A
TA
Department of Health and Clinical Science, Center for Chronic Disease Control, University of Massachusetts Lowell, Lowell, MA 01854, USA.
Behr
S R
SR
Nicolosi
R J
RJ
D000818:Animals; D002364:Caseins; D002482:Cellulose; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D004032:Diet / Q000592:standards*; D004043:Dietary Fiber / Q000008:administration & dosage*; D005260:Female; D005685:Galactans / Q000008:administration & dosage*; D017408:Guidelines as Topic; D008252:Macaca fascicularis; D008351:Mannans / Q000008:administration & dosage*; D053149:Plant Gums; D030262:Soybean Proteins / Q000008:administration & dosage*
D002364:Caseins; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004043:Dietary Fiber; D005685:Galactans; D008351:Mannans; D053149:Plant Gums; D030262:Soybean Proteins; D002482:Cellulose; C007894:guar gum