A very low calorie diet (VLCD) results in cardiac remodeling and improved diastolic function. It is unknown how long these effects sustain after reintroduction of a regular diet. We aimed to assess the long-term effects of initial weight loss by VLCD on cardiac dimensions and function in type 2 diabetes mellitus (T2DM) patients. Fourteen insulin-dependent T2DM patients (mean ± SEM: age 53 ± 2 years; BMI 35 ± 1 kg/m(2)) were treated by a VLCD (450 kcal/day) during 16 weeks. Cardiac function and myocardial triglyceride (TG) content were measured by magnetic resonance imaging and spectroscopy at baseline, after a 16-week VLCD and after 14 months of follow-up on a regular diet. BMI decreased from 35 ± 1 to 28 ± 1 kg/m(2) after VLCD and increased again to 32 ± 1 kg/m(2) at 18 months (both P < 0.05 vs. baseline). Left ventricular (LV) end-diastolic volume index increased after the 16-week VLCD (80 ± 3 to 89 ± 4 ml/m(2), P < 0.05) and remained increased after follow-up (90 ± 3 ml/m(2); P < 0.05 vs. baseline) at comparable filling pressures. The improvement in LV diastolic function after the 16-week VLCD, was sustained at 18 months [early (E)/atrial (A) diastolic filling phase ratio: 0.96 ± 0.07 (baseline); 1.12 ± 0.06 (after VLCD); 1.06 ± 0.07 (18 months, P < 0.05 vs. baseline)]. Myocardial TG content decreased after the 16-week VLCD [0.74 (0.41-1.10) to 0.45 (0.31-0.54) %, P < 0.05], but returned to baseline levels at 18 months [0.76 (0.65-1.32) %]. Weight reduction by a 16-week VLCD in T2DM patients results in sustained cardiac remodeling and improved diastolic function after 14 months of follow-up, despite weight regain on a regular diet.