Short-term effects of severe dietary carbohydrate-restriction advice in Type 2 diabetes—a randomized controlled trial


Correspondence: Mark Daly, Diabetes and Vascular Health Centre, Royal Devon and Exeter NHS Trust, Barrack Road, Exeter EX2 5DW, UK. E-mail:


Objective  This study sought to examine the effects of a 3-month programme of dietary advice to restrict carbohydrate intake compared with reduced-portion, low-fat advice in obese subjects with poorly controlled Type 2 diabetes.

Research design and methods  One hundred and two patients with Type 2 diabetes were recruited across three centres and randomly allocated to receive group education and individual dietary advice. Weight, glycaemic control, lipids and blood pressure were assessed at baseline and 3 months. Dietary quality was assessed at the end of study.

Results  Weight loss was greater in the low-carbohydrate (LC) group (−3.55 ± 0.63, mean ± sem) vs. −0.92 ± 0.40 kg, P = 0.001) and cholesterol : high-density lipoprotein (HDL) ratio improved (−0.48 ± 0.11 vs. −0.10 ± 0.10, P = 0.01). However, relative saturated fat intake was greater (13.9 ± 0.71 vs. 11.0 ± 0.47% of dietary intake, P < 0.001), although absolute intakes were moderate.

Conclusions  Carbohydrate restriction was an effective method of achieving short-term weight loss compared with standard advice, but this was at the expense of an increase in relative saturated fat intake.