Oats and soy in lipid-lowering diets for women with hypercholesterolemia: is there synergy?
OBJECTIVE
To study possible synergistic effects of oats and soy on reducing total and low-density lipoprotein cholesterol (LDL-C) concentrations in human beings and the efficacy and feasibility of including these adjustments to a National Cholesterol Education Program Step I diet. SUBJECT/SETTING: One hundred twenty-seven postmenopausal women with moderate hypercholesterolemia were recruited from a large Midwestern workforce and senior centers in the surrounding community. Intervention and clinical visits were conducted in these same facilities.


METHODS
After a 3-week lead-in period on the Step I diet, participants were randomly assigned to 1 of 4 dietary treatments for an additional 6 weeks: an oats/milk group, a wheat/soy group, an oats/soy group, and a wheat/milk group. Clinical measurements included blood draws, body weight and height, blood pressure, and medical history data. Three-day food records were collected at baseline and Weeks 3 and 9 of the intervention. Randomization was stratified based on the status of hormone replacement therapy and was blocked with sizes 4 or 8 for group assignment.


RESULTS
After 3 weeks on the Step I diet, total cholesterol, LDL-C, and triglyceride levels; total fat and saturated fat intake, dietary cholesterol intake, Keys score, and body mass index were all reduced. Following an additional 6 weeks on the Step I diet plus intervention, total cholesterol and LDL-C were further reduced for both the oats/soy group and oats/milk group. There were no significant further changes in total cholesterol, LDL-C, or high-density lipoprotein cholesterol levels in the wheat/soy and wheat/milk groups. Body mass index remained stable in all groups from Week 3 to Week 9.


CONCLUSIONS
Nonpharmacologic dietary interventions like the Step I diet are feasible in a community setting and can produce rapid and significant lipid-lowering benefits. Daily consumption of 2 servings of oats can contribute to further lipid alterations in this population although soy intake at this dose may not. Palatability and convenience are important considerations in achieving dietary adherence.
Van Horn
L
L
Department of Preventive Medicine, Northwestern University Medical School, Chicago, IL 60611, USA.
Liu
K
K
Gerber
J
J
Garside
D
D
Schiffer
L
L
Gernhofer
N
N
Greenland
P
P
D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D018554:Avena / Q000378:metabolism*; D001794:Blood Pressure; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D015930:Diet Records; D018752:Diet, Fat-Restricted; D004041:Dietary Fats / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy*; D008875:Middle Aged; D008892:Milk; D010349:Patient Compliance; D010353:Patient Education as Topic; D017698:Postmenopause; D013025:Glycine max / Q000378:metabolism*; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood; D014908:Triticum
D008078:Cholesterol, LDL; D004041:Dietary Fats; D014280:Triglycerides; D002784:Cholesterol