Intermittent energy restriction in type 2 diabetes: A short discussion of medication management

Table 1 Summary of trials

Ref.	Design	Duration	Subjects	Aim	Diet groups	Medication protocol
Wing et al[7]	Randomized parallel study	50 wk 1-yr follow-up	n = 93 Male/female: 33/60 Mean age: 51.8 ± 9.7 Mean diagnosis (yr): 6.8 ± 6.1	Effects of a weight control program, with and without 2 × 12-wk VLCD restriction	VLCD = 400-500 kcal via liquid or food-based diet from 1-12 wk and from 24-36 wk. LCD was followed at all other times LCD = 1000-1200 kcal	All medications (inc. insulin) were discontinued at the start of the trial. Insulin was discontinued and monitored for 3 d. Dosages of oral medications or insulin were reinstated if the mean of two fasting blood glucose levels averaged > 13.3 mmol/L over a fortnight. Dosages increased on a case-by-case basis
Kelley et al[8]	Single arm study	24 wk	n = 7 Male/female: 2/5 Mean age: 59 Mean diagnosis (yr): N/A	Evaluating the efficacy of VLCD treatment in obese T2DM participants	VLCD = 400-800 kcal via liquid and food-based diet	Discontinued all oral glycemic medication 3 wk before commencement on the VLCD
Williams et al[9]	Randomized parallel study	20 wk	n = 54 Male/female: 23/31 Mean age: 51.9 ± 7.8 Mean diagnosis (yr): N/A	Evaluating the efficacy of intermittent VLCD restriction on weight loss and glycemic control compared to moderate calorie restriction	VLCD = 400-600 kcal via food-based diet. LDC (1500-1800 kcals) at all other times 2 groups: 1-d: 1 d/wk plus 5 consecutive days in week 2 5-d: 5 d/wk for 15 wk	Discontinued all oral glycemic medication 2 wk before the trial and people with fasting glucose > 16.7 mmol/L were excluded. People using insulin were also excluded Medications were only reinstated if fasting BGLs (measured twice weekly) increased > 13.9 mmol/L. Restarted medication occurred at half of the original dose
Uusitupa et al[10]	Single arm study	12 wk	n = 10 Male/female: 6/4 Mean age: 51 ± 2.2 Diagnosis (yr): Ranged 4-16	Evaluating the effects of weight loss using a VLCD on metabolic control and cardiovascular risk factors in obese participants with T2DM	VLCD = 500-800 kcals via liquid and food-based diet	Discontinued all oral glycemic medications before the start of the trial

VLCD: Very low calorie diet; LCD: Low calorie diet; T2DM: Type 2 diabetes mellitus; BGL: Blood glucose levels.