The results of a massive federally-funded study that examined the impact of a low-fat diet on the health of tens of thousands of American women are generating controversy. The research, which appears in the latest issue of the Journal of the American Medical Association, seems to contradict the widely-held view that a low-fat diet can help guard against killers like cancer and heart disease. Researchers found no evidence of any protective effect following the dietary changes. The study, which was funded by the Women's Initiative of the National Institutes of Health, followed 49,000 women over eight years. Critics challenge the study's design, arguing that patients began their diets too late (in most cases in their fifties or sixties) and that the low-fat diets they followed are outmoded and have since been replaced with more effective versions. Article