Abstract
ImportanceIntermittent energy restriction is an alternative weight loss method that is becoming popular; however, to date, there are no long-term clinical trials of intermittent energy restriction in patients with type 2 diabetes.ObjectiveTo compare the effects of intermittent energy restriction (2 days per week) with those of continuous energy restriction on glycemic control and weight loss in patients with type 2 diabetes during a 12-month period.Design, Setting, and ParticipantsAdult participants (N = 137) with type 2 diabetes were randomized 1:1 to parallel diet groups (intermittent energy restriction [n = 70] or continuous energy restriction [n = 67]) between April 7, 2015, and September 7, 2017, at the University of South Australia. Medications likely to cause hypoglycemia were reduced at baseline according to the medication management protocol.InterventionsAn intermittent energy restriction diet (500-600 kcal/d) followed for 2 nonconsecutive days per week (participants followed their usual diet for the other 5 days) or a continuous energy restriction diet (1200-1500 kcal/d) followed for 7 days per week for 12 months.Main Outcomes and MeasuresThe primary outcome was change in hemoglobin A1c (HbA1c) level, with equivalence prespecified by a 90% CI margin of ±0.5%. The secondary outcome was weight loss with equivalence set at ±2.5 kg (±1.75 kg for fat mass loss and ±0.75 kg for fat-free mass loss). All other outcomes were tested for superiority.ResultsOf the 137 randomized participants (77 women and 60 men; mean [SD] age, 61.0 [9.1] years; mean [SD] body mass index, 36.0 [5.8] [calculated as weight in kilograms divided by height in meters squared]; and mean [SD] HbA1c level, 7.3% [1.3%]), 97 completed the trial. Intention-to-treat analysis showed similar reductions in mean (SEM) HbA1c level between the continuous and intermittent energy restriction groups (–0.5% [0.2%] vs –0.3% [0.1%]; P = .65), with a between-group difference of 0.2% (90% CI, –0.2% to 0.5%) meeting the criteria for equivalence. Mean (SEM) weight change was similar between the continuous and intermittent energy restriction groups (–5.0 [0.8] kg vs –6.8 [0.8] kg; P = .25), but the between-group difference did not meet the criteria for equivalence (–1.8 kg; 90% CI, –3.7 to 0.07 kg), nor did the between-group difference in fat mass (–1.3 kg; 90% CI, –2.8 to 0.2 kg) or fat-free mass (–0.5 kg; 90% CI, –1.4 to 0.4 kg). There were no significant differences between groups in final step count, fasting glucose levels, lipid levels, or total medication effect score at 12 months. Effects did not differ using completers analysis. Hypoglycemic or hyperglycemic events in the first 2 weeks of treatment were similar between the continuous and intermittent energy restriction groups (mean number [SEM] of events, 3.2 [0.7] vs 4.9 [1.4]; P = .28), affecting 35% of participants (16 of 46) using sulfonylureas and/or insulin.Conclusions and RelevanceIntermittent energy restriction is an effective alternative diet strategy for the reduction of HbA1c and is comparable with continuous energy restriction in patients with type 2 diabetes.Trial Registrationanzctr.org.au Identifier: ACTRN12615000383561
Highlights
The health care costs of overweight, obesity, and type 2 diabetes are increasing,[1] and conventional weight-loss diets with daily energy restriction are difficult to adhere to in the long term.[2]
Intention-totreat analysis showed similar reductions in mean (SEM) hemoglobin A1c (HbA1c) level between the continuous and intermittent energy restriction groups (–0.5% [0.2%] vs –0.3% [0.1%]; P = .65), with a betweengroup difference of 0.2% meeting the criteria for equivalence
The baseline HbA1c level accounted for 35% and the change in visceral adipose tissue accounted for 17% of the variance in the change in HbA1c level at 12 months, with no effect of treatment group
Summary
The health care costs of overweight, obesity, and type 2 diabetes are increasing,[1] and conventional weight-loss diets with daily energy restriction are difficult to adhere to in the long term.[2]. We previously published a pilot trial that demonstrated that a 2-day intermittent energy restriction diet provides an effective alternative method for both glycemic control and weight loss compared with a continuous energy restriction diet over a 3-month period.[10] The objective of this randomized noninferiority trial was to ascertain the long-term effects of a 2-day intermittent energy restriction diet compared with continuous energy restriction during a 12-month period for patients with type 2 diabetes. We hypothesized that equal improvements to hemoglobin A1c (HbA1c) level and weight would occur, as seen in our 3-month pilot trial, offering a successful alternative treatment strategy for use in clinical practice
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
