a recent study followed 900,000 us adults from 1982 to 1998. at baseline, all participants were screened and determined to be cancer free and their body mass index (bmi) was calculated. body mass index is a measure of obesity that is calculated using a person’s height and weight. subjects were separated into the following groups according to their bmi: (a) normal weight, (b) slightly overweight, (c) moderately overweight and (d) greatly overweight. 57,145 deaths from cancer occurred in the population during the follow-up period.