Effects of a very-low-calorie diet on long-term glycemic control in obese type 2 diabetic subjects.

We tested the hypothesis that the use of a very-low-calorie diet (VLCD) in combination with behavior modification would promote long-term glycemic control in obese type 2 diabetic subjects. Thirty-six diabetic subjects were randomly assigned to a standard behavior therapy program or to a behavior therapy program that included an 8-week period of VLCD. The behavior therapy group consumed a balanced diet of 4200 to 6300 J/d throughout the 20-week program. The VLCD group consumed a balanced diet of 4200 to 6300 J for weeks 1 to 4, followed by a VLCD (1680 J/d of lean meat, fish, and fowl) for weeks 5 to 12. The VLCD group then gradually reintroduced other foods during weeks 13 to 16 and consumed a balanced diet of 4200 to 6300 J/d for weeks 17 to 20. Thirty-three of the 36 subjects completed the 20-week program and the 1-year follow-up. Use of the VLCD produced greater decreases in fasting glucose at the end of the 20-week program and at 1-year follow-up and greater long-term reductions in HbA1. The VLCD group also had greater weight losses at week 20, but weight losses from pretreatment to 1-year follow-up were similar in the two treatment groups. The improved glycemic control with the VLCD appeared to be due to increased insulin secretion, but further research is needed to confirm this.

RCT Entities:   Population Interventions Outcomes