Is diet alone enough for weight loss?

The most effective way is by surgery such as gastric banding, which gives rapid, often dramatic weight loss. It is a drastic measure though and is very expensive and obviously not appropriate for most of us!

Most people should focus on lifestyle modification with diet and exercise. I still hear some health professionals saying that you can't lose weight and keep it off with diet alone. This is rubbish. Diet plus exercise is about 20% more effective than diet alone, but long-term diet can be effective and should be the primary intervention. Remember that people in food shortages will all lose weight with time regardless of whether they exercise or not.