Moderate weight loss achieved through lifestyle interventions positively impacts on a number of metabolic and cardiovascular risk factors. Clinical studies have shown that sustained moderate weight loss lowers blood pressure, improves glucose control, and improves dyslipidaemia as well as inflammatory, haemostatic, and fibrinolytic factors. In addition, it is associated with the prevention of progression to Type 2 diabetes in at-risk subjects. Furthermore, increasing physical fitness is associated with increases in HDL cholesterol and reductions in all-cause mortality. However, there is, as yet, only indirect evidence that modification of risk factors through weight loss will reduce mortality.