A randomized clinical trial testing treatment preference and two dietary options in behavioral weight management: preliminary results of the impact of diet at 6 months--PREFER study.
OBJECTIVE
The PREFER study objectives were to examine potential differences in weight loss during a standard behavioral intervention between subjects assigned to one of two calorie- and fat-restricted diets [standard behavior treatment (SBT) and lacto-ovo-vegetarian ([SBT+LOV)], with or without regard to their preferred dietary treatment. This article reports the differences in outcomes between diet groups after the first 6 months of the intervention.


METHODS
The study used a four-group design. Subjects (n = 182) were randomized to a treatment preference group and then to a dietary treatment group. For this report, preference groups were combined to permit comparisons by dietary treatment only (SBT, n = 98; SBT+LOV, n = 84). Additional analyses compared SBT+LOV subjects who were 100% adherent (did not consume any meat, fish, or poultry, n = 47) to those who were <100% adherent (n = 24).


RESULTS
Significant differences were seen in the baseline to 6-month change scores between the two groups for carbohydrate consumption (p = 0.013), protein consumption (p < 0.001), polyunsaturated-to-saturated fat ratio (p = 0.009), and low-density lipoprotein-cholesterol (LDL-C) level (p = 0.013). Among SBT+LOV subjects, those who were 100% adherent experienced greater reductions in weight (p < 0.001), total cholesterol (p = 0.026), LDL-C (p = 0.034), and glucose (p = 0.002) and consumed less fat (p = 0.030) compared with those who were <100% adherent.


CONCLUSIONS
Differences between dietary treatment groups at 6 months were minimal, most likely because one-third of the SBT+LOV group did not follow the vegetarian diet and because both groups had the same calorie and fat restrictions. SBT+LOV subjects who were 100% adherent were more successful at both weight loss and cholesterol reduction than those who were <100% adherent, suggesting that vegetarian diets are efficacious for weight and cholesterol control.
Burke
Lora E
LE
School of Nursing, University of Pittsburgh, 3500 Victoria Street, 415 Victoria Building, Pittsburgh, PA 15261, USA. lbu100@pitt.edu
Styn
Mindi A
MA
Steenkiste
Ann R
AR
Music
Edvin
E
Warziski
Melanie
M
Choo
Jina
J
D000328:Adult; D001521:Behavior Therapy; D002784:Cholesterol / Q000097:blood; D004038:Diet, Reducing / Q000523:psychology; D014676:Diet, Vegetarian / Q000523:psychology; D005260:Female; D005518:Food Preferences; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000628:therapy*; D010349:Patient Compliance; D013997:Time Factors; D016896:Treatment Outcome
D002784:Cholesterol