Dear Kobus
To lose weight you need to basically change your lifestyle. Reduce your energy intake by eating an energy-reduced, low-fat, high-fibre diet (click on 'Diet' at the top of this page, 'Weight loss' , ‘Balanced diet' and then on 'Slimming Diet' for a copy of such a diet), and increasing your energy output by doing regular exercise (running, jogging, skipping, cycling, swimming, join a gym or Walk for Life). Because you have such a large amount of weight to lose, I would also suggest that you ask your dr about Xenical. Xenical is a real fat-trapper that prevents you from absorbing fat from what you eat. Xenical is, however expensive so it would help if your dr could motivate for this medication to be paid for by your medical aid. You would use the Xenical with a very-low-fat-diet and this will help you to start losing. So see if you can get Xenical prescribed for your condition, seeing that the overweight is a direct threat to your health.
Best regards
DietDoc