How much weight do you have to lose before you start getting any health benefits? Surprisingly, it's far less than you might think. Researchers in Australia have discovered that a weight loss of just 6 kg (13 lbs) is enough to reverse most of the damage that can be caused by being overweight or obese. In particular, the weight loss can kick-start the immune system, and stop inflammatory processes that could otherwise lead to coronary heart disease, say researchers from Sydney's Garvan Institute of Medical Research. The researchers studied the impact of a weight loss programme on a group of obese individuals, who either had type 2 diabetes or who were pre-diabetic. They were limited to a diet of up to 1600 calories a day for 24 weeks. (Source: Journal of Clinical Endocrinology & Metabolism, 2010; doi: 10.1210/jc.2009-2371).