Evidence appears to be fairly conclusive that obesity has adverse effects on health and longevity when the relative body weight is 40 percent above desirable weight based on insurance industry tables of weights. The close association between obesity, hypertension, hypercholesterolemia, non-insulin dependent diabetes mellitus, an excess of certain cancers and other medical problems makes it imperative that interventions be directed to change the lifestyles and behaviors of individuals who are overweight. The Stanford Weight Control Project (SWCP) trial examined the effects of weight loss on cardiovascular disease risk factors.