As others have said below, losing weight too rapidly is not the answer. It wreaks havoc with your body, slows your metabolism down and means you will be fighting with your weight in the future. Instead, look to reduce the amount of starchy and fatty foods that you eat, focus on nourishing yourself with lean protein, fresh fruit and vegetables. Get gentle exercise that you enjoy such as walking, yoga, dancing etc (and I would agree with Scott39 qigong is brilliant!). You don't need to punish yourself! Depending on how much weight you need to lose and your metabolism you could easily and healthily lose one or two pounds a week through this method. That's a dress size in 6 weeks - it's fast enough! If you're interested in getting some one-to-one support with this have a look at http://www.dietcare.com
for your nearest clinic - first consultations are free!