We report the case of a 59-year-old severely obese man with coexisting type 2 diabetes, hypertension and dyslipidaemia who was treated with a very-low-calorie diet (VLCD) program for 12 months. He continued to lose weight during the treatment, with marked improvement in his comorbidities and no adverse effects. This case demonstrates that prolonged use of a VLCD under close medical supervision is safe and effective in certain obese patients.