The effect of short periods of caloric restriction on weight loss and glycemic control in type 2 diabetes.
OBJECTIVE
To determine whether an intermittent very-low-calorie diet (VLCD) improves weight loss and glycemic control more than moderate caloric restriction alone.


METHODS
Individuals with type 2 diabetes (n = 54) who were > or = 20% over ideal body weight participated in a 20-week behavioral weight control program. Subjects were randomized to either a standard behavioral therapy (SBT) group or to one of two VLCD groups. SBT subjects received a 1,500-1,800 kcal/day diet throughout. Both VLCD groups followed a VLCD for 5 consecutive days during week 2, followed by either intermittent VLCD therapy for 1 day/week for 15 weeks (1-day) or for 5 consecutive days every 5 weeks (5-day), with a 1,500-1,800 kcal/day diet at other times.


RESULTS
Both VLCD groups lost more weight than the SBT group over the 20 weeks (P = 0.04). Although the groups did not differ in fasting plasma glucose (FPG) changes at 20 weeks, more subjects in the 5-day group attained a normal HbA1c when compared with the SBT group (P = 0.04). This benefit was independent of the effects of weight loss. The best predictor of overall change in FPG and HbA1c was the FPG response during the first 3 weeks of the program.


CONCLUSIONS
Periodic VLCDs improved weight loss in diabetic subjects. A regimen with intermittent 5-day VLCD therapy seemed particularly promising, because more subjects in this group attained a normal HbA1c. Moreover, the glucose response to a 3-week period of diet therapy predicted glycemic response at 20 weeks, and it was a better predictor of the 20-week response than initial or overall weight loss.
Williams
K V
KV
Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania, USA. kvw+@.pitt.edu
Mullen
M L
ML
Kelley
D E
DE
Wing
R R
RR
D000328:Adult; D000368:Aged; D001521:Behavior Therapy; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003920:Diabetes Mellitus / Q000178:diet therapy / Q000503:physiopathology / Q000628:therapy*; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy / Q000503:physiopathology / Q000628:therapy*; D004038:Diet, Reducing; D002149:Energy Intake; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity; D012044:Regression Analysis; D013997:Time Factors; D014280:Triglycerides / Q000097:blood; D015431:Weight Loss
D001786:Blood Glucose; D002784:Cholesterol; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D006442:Glycated Hemoglobin; D014280:Triglycerides